seismicity

Etna Week (Part 2) - The current dynamics and activity of Etna

eklemetti — Wed, 18 Aug 2010 04:14:53 +0000

Etna Week (Part 2) - The current dynamics and activity of Etna

This is Part 2 of 3 from guest blogger Dr. Boris Behncke. Check out Part 1 here.

The current dynamics and activity of Etna
by guest blogger Dr. Boris Behncke

The recent behavior of Etna is characterized by nearly continuous eruptive activity from the summit craters and eruptions from new vents on the flanks at intervals of a few years to decades. Summit eruptions vary from quiet lava emission to mild Strombolian explosions to high-discharge-rate Hawaiian to sub-Plinian style lava and fire fountaining accompanied by the emplacement of fast-moving lava flows; usually the strongest activity concentrates in episodes lasting from a few tens of minutes to a few hours. Most flank eruptions are predominantly effusive - that is, characterized by the emission of lava flows, and explosive activity during these events is often limited to Strombolian explosions or mild spattering. This leads to the emplacement of extensive lava flow-fields and only minor cones are built at the eruptive vents, including the smallest constructive volcanic features, called hornitos (Spanish: "small furnaces").

Pyroclastic constructs on Etna come in all forms and sizes. The photograph at top shows a cluster of steep, narrow spires a few meters tall built up around small vents by the ejection of liquid blobs of lava (spattering activity), seen against the backdrop of the huge composite cone of the Southeast Crater, one of the summit craters of Etna. The conspicuous yellow hue is from sulfur deposits. The bottom photograph shows the largest pyroclastic flank cone formed during the historical period, Monti Rossi at about 700 m elevation near the village of Nicolosi, on the south flank of Etna. The name, literally, means "the red mountains" - the plural stands for the two summit peaks, the crater actually lying between them; but the original name - Monte della Ruina, "mountain of devastation" - more accurately refers to the catastrophic impact of this eruption. The cone is approximately 250 m tall from base to top. Photos taken in 1999 and 2000 by Boris Behncke

Some flank eruptions, however, show much more intense explosive activity, like the 2001 and 2002-2003 eruptions, and a number of previous eruptions as in 1852-1853, 1879, 1886, and 1892. Conspicuous pyroclastic cones (also called cinder cones or scoria cones) are formed during such explosive activity, which can be up to a few hundred meters tall, like the prominent double-peaked Monti Rossi cone formed during the unusually voluminous and explosive 1669 eruption on the south flank of Etna. A typical feature of the flank vents is that each erupts only once, like the eruptive centers in monogenetic cone fields worldwide (e.g., the famous "new volcano" ParÃcutin in Mexico, 1943-1952). As a matter of fact, the numerous pyroclastic cones of Etna could be considered a monogenetic cone field, were it not for the huge central volcano on whose flanks they are sitting.

Flank eruptions represent a considerable hazard for the populated areas on the lower flanks of the mountain, which are home to approximately one million people. During the historical period, new flank vents have occasionally opened within those areas that are now densely urbanized, especially on the southern and southeastern flanks, most recently in 1669 near the village of Nicolosi. During the past 1000 years, lava flows have reached the coast of the Ionian sea on three occasions, in ~1030, 1224, and 1669. The map below shows the extent of historical lava flows, distinguishing those of flank eruptions (in different shades of pink, yellow and red) from those emitted during summit eruptions (in green). It is evident that summit lava flows have never come anywhere close to the populated areas and therefore summit activity poses no immediate threat to those areas.

Map of historical lava flows of Etna, distinguishing summit from flank eruptions. Modified from Crisci et al. (2010)

Evolution of the summit area
The summit area of Etna has undergone profound changes in the past century. Until 1911, there was a single large crater at the summit, about half a kilometer wide, and truncating a broad cone about 300 m tall, which had grown since a major summit collapse accompanying the large 1669 flank eruption. This crater was known as the Central Crater. At the beginning of the 20th century, it was a funnel-shaped pit about 200 m deep, but intermittent eruptive activity on its floor led to its gradual filling, and in the mid-1950s, lava flows for the first time overflowed from the Central Crater onto the upper flanks of the volcano. Vigorous activity from several vents within the crater in the early 1960s led to the complete filling and obliteration of the Central Crater, and two large cones built up around the two main vents, the Voragine ("Big Mouth") that had been present since 1945, and a smaller vent known as "the 1964 crater". In 1968, a third vent opened, which became known as Bocca Nuova ("New Mouth"), and which progressively enlarged in diameter mostly due to the caving in of its unstable rims.

For much of the 1970s to 1990s, the evolution of the Voragine and the Bocca Nuova was characterized by periodic intracrater activity and rim collapse, leading to their growth in diameter, until the two pits began to coalesce with only a thin septum remaining between the two, known as the "diaframma" (diaphragm). During a period of exceptionally intense summit eruptions in 1997-1999, both craters were filled to overflowing before subsidence of magma in their conduits led to the formation of new collapse pits, which gradually enlarged and coalesced into a single large depression, Etna's new Central Crater.

Aerial views of Etna's summit area showing the evolution from the single Central Crater in the early 20th century to the currently four summit craters. Top photograph was taken in the 1920s, when the Northeast Crater was already present (but is barely discernible in this view); the size and depth of the Central Crater is well recognizable here. The view is from the west. Center photo is of 1961 and shows the Central Crater filled-to-overflow with pyroclastic cones and lava; the much smaller Northeast Crater is seen behind the Central Crater to the left. The view is from the south. Photograph at bottom was taken in May 2008, the Bocca Nuova and Voragine are in the upper center, nearly coalescing into a new Central Crater, whereas the Northeast Crater is emitting a dense white vapor plume at right, and the Southeast Crater is at center left, showing conspicuous light-colored sulfur deposits lining its rim. The view is from the east. Photographers for top and center photographs unknown, bottom photo by Stefano Branca (INGV-Catania)

In the spring of 1911, a collapse pit opened at the northeastern base of the central summit cone, from which issued a vapor plume but which showed no eruptive activity until 1917. This pit became known as "the Northeast subterminal Crater" (the term subterminal is applied to eruptive vents lying close to Etna's summit craters and showing a eruptive behavior different from the vents of flank eruptions); it is now called Northeast Crater. The new crater remained a pit until 1923, when a small cone grew within and filled the pit, leading to the first lava overflows from the Northeast Crater. In the 1950s, cone growth intensified, as the crater became the site of virtually continuous, mild Strombolian activity accompanied by slow lava emission; this type of activity was termed "persistent" and for a long time was believed to represent the most common type of Etnean eruptive manifestation. In 1977, however, the Northeast Crater switched to a more dramatic form of volcanism, which proved highly efficient in making it become the highest point on Etna - brief but violent episodes of high lava fountaining with voluminous, fast-moving lava flows and tall tephra columns.

The Northeast Crater showing different types of eruptive activity. Top photo, taken in 1969, shows the cone of the Northeast Crater nearly as tall as the rim of the former Central Crater (in the foreground), and displaying weak Strombolian activity from its summit, while lava quietly issues from a small crack on the left side of the cone. This activity lasted with few interruptions from 1955 until 1971, and again from 1974 until 1977. Photographer T. Micek (?). The bottom photograph shows one of about twenty episodes of violent fire fountaining and tall tephra plumes that occurred between July 1977 and March 1978; this was one of the latest episodes of that series. View is from the village of Monterosso on the southeast flank of Etna, photo by Carmelo Sturiale.

By 1978, the Northeast Crater had grown to about 3340 m elevation and thus become the highest point ever measured on Etna. It produced a few more episodes of lava fountaining in late-1980 and early-1981, which brought its height to 3350 m. On 24 September 1986, an unprecedentedly violent eruptive episode caused a reduction in height by 10 m of its cone, and further collapse occurred throughout the following decade. Although the Northeast Crater went through another phase of intense activity in 1995-1996, its height continued to decrease, and in 2007 was 3329.6 m (Neri et al., 2008).

The Southeast Crater seen from the air immediately after its formation in spring 1971 (top) and in May 2008 (bottom). Note that the field of view in the latter photo is much wider than in the earlier. Photos taken by Carmelo Sturiale and Boris Behncke

The latest addition to Etna's summit crater family is the Southeast Crater, which formed during a flank eruption in May 1971 at the southeastern base of the central summit cone as a sort of pressure valve - while lava was emitted a few kilometers further downslope to the northeast, it emitted vapor-rich ash clouds for a couple of weeks. It then remained quiet until spring 1978 and then sprang to life with high lava fountains accompanying a series of flank eruptions in rapid succession - April-June, August, and November 1978, and August 1979. Since then, it has been the most persistently active vent on Etna, and its appearance on the stage was accompanied by a marked change in the eruptive behavior of the volcano. As a matter of fact, since the birth of the Southeast Crater, Etna has practically doubled its average output rate (Behncke and Neri, 2003a).

The Southeast Crater has grown much more rapidly than the Northeast Crater, and nearly 40 years after its birth its cone stands approximately 300 m above the site where it came to life in 1971, reaching a height of 3290 m as of 2007. This rapid growth is the result of numerous periods of frantic eruptive activity which are unparalleled in the documented history not only of Etna but of all volcanoes on Earth. The culmination was a series of 64 episodes of violent lava or fire fountaining between January and June 2000, followed by two more in August and 16 more in May-July 2001 (Behncke et al., 2006). The Southeast Crater has erupted more recently in 2006 and 2007-2008, again producing numerous episodes of strong Strombolian activity and lava fountaining, the latest - and possibly most violent - on 10 May 2008, when lava flows advanced 6.4 km in 4 hours, an unprecedented value for Etnean summit eruptions.

What are the reasons for such variable and, for a basaltic volcano, often unusually violent explosive behavior?

Eruption types and styles
It seems that much of the explosivity of Etna is driven by magmatic gases, foremost water vapor (H₂O) and carbon dioxide (CO₂). Etna is emitting significant quantities of these gas species, up to 200,000 metric tons of water vapor and about 20,000 tons of carbon dioxide per day. Eruptions tend to be more explosive when magma rises fast, which is the case when batches of new primitive magma enter into the plumbing system of the volcano, so that the most explosive eruptions of Etna in the past few thousand years have also produced the most mafic magmas (Coltelli et al., 2005; Kamenetsky et al., 2007). In particular, a powerful sub-Plinian eruption about 3930 years before present produced picritic magma, which was also extremely enriched in CO₂. In contrast, the Plinian eruption of 122 BC was apparently triggered by the sudden decompression of the magmatic system, which led to the catastrophic exsolution of gas although the pre-eruptive water content of the magma was found to be only about 1 weight-% (Del Carlo and Pompilio, 2004).

Hypothetical and simplified scheme of the magmatic plumbing system of Etna, illustrating magma transport feeding summit activity and the two different types (lateral vs. eccentric) flank eruptions, from Behncke and Neri (2003b)

Most magma ascends to the surface through the central conduit system of Etna, which leads to the frequent summit activity. Unless magma ascent is very rapid, much gas is lost from the magma during its ascent to the surface, and significant volumes of relatively gas-poor magma are stored in the shallow plumbing system of the volcano. During many flank eruptions of Etna, such gas-poor magma exits laterally from the central conduits, resulting in relatively weak or almost no explosive activity but copious lava outflow. Most flank eruptions during the 20th century were of this type; they are commonly called "lateral" flank eruptions. Typically such eruptions are accompanied by the cessation of summit activity and some collapse at the summit craters, as the central conduit system is drained of magma.

Extremes in eruptive styles at Etna: totally non-explosive extrusion of gas-poor lava near the Southeast Crater in 1999 (top), and the 10-km-high eruption column formed during a sub-Plinian eruption from the Voragine on 22 July 1998 as seen from Catania. Photos taken by Boris Behncke and Sandro Privitera

Another type of Etnean flank eruption is characterized by much more pronounced explosive activity, resulting in the emission of significant volumes of ash even for prolonged periods of up to several months, as in 1892, 2001, and 2002-2003. These eruptions occur when magma, rather than rising through the central conduits, pushes its way forcefully through the flank of the volcano to form new conduits called "eccentric" or "peripheral" (Rittmann, 1964; Neri et al., 2005). Being in a closed system until eruption, the magma does not lose significant amounts of its gas during ascent, and therefore the ensuing activity is considerably more explosive. The 1974 and 2002-2003 eccentric eruptions did in fact produce more tephra than lava (Andronico et al., 2004; Corsaro et al., 2009), belying the widespread notion of Etna being a rather non-explosive volcano!

Eruptions and flank instability
The question why Etna makes flank eruptions at all is not easy to answer. Certainly the fact that the volcano lies above the intersection of several main regional fault systems helps in rendering its flanks unstable and subject to fracturing. Mazzarini and Armienti (2001) demonstrated that the distribution of Etna's flank cones is largely controlled by intersections between tectonic lines of weakness. It has also been suggested (e.g., Chester et al., 1985) that the hydrostatic (or rather "magmastatic") pressure exerted on the conduit walls by the rising magma column within the conduit might lead to the opening of lateral cracks through which the magma could escape to feed flank eruptions. Bousquet and Lanzafame (2001) specified that magma transfer from the central conduits into the flank occurred in a more or less horizontal manner, rather than rising upward vertically. All of these scenarios concerned exclusively lateral flank eruptions, not eccentric ones, which had effectively been nearly forgotten prior to the 2001 and 2002-2003 eruptions.

The Pernicana fault cuts through the northeastern flank of Etna, from an elevation of about 2000 m at the Northeast Rift, down to sea level near the village of Fondachello. From Neri et al. (2004)

Displacement along the Pernicana fault during the massive flank movement of 2002, along the Fornazzo-Linguaglossa road (top) and the Catania-Messina highway (bottom). From Neri et al. (2004)

Since the early 1990s scientists (Borgia et al, 1992; Lo Giudice and RasÃ , 1992; Rust and Neri, 1996; Bousquet and Lanzafame, 2001) proposed that a large portion of the volcano, encompassing its eastern and southern flank sectors, was subject to lateral sliding, much in the same manner as the southern flank of KÄ«lauea on Hawai'i. There was some debate as for the cause of the sliding - was it caused by gravitational pull, the push of accumulating magma below the volcano, or by more shallow intrusion of magma into the flanks? Also the extent of the mobile sector was not unanimously defined; whereas there was agreement that the northern boundary of this sector was defined by the transcurrent (mostly horizontally moving) Pernicana fault, the southern or southwestern boundary was variously attributed to different fault systems cutting the southeastern and southwestern flanks of Etna. It is now known that the extreme southwestern boundary is the Ragalna fault system (Rust and Neri, 1996; Rust et al., 2005; Neri et al., 2007).

Speculation became truth in the fall of 2002, when a large sector of the eastern and southeastern flank of Etna underwent a massive move toward the Ionian Sea. During a powerful and complex flank eruption in the summer of 2001, the southern flank and summit area of the volcano were violently ripped open, and the eastern flank started to move away from the remainder of the mountain at accelerating speed. Though this was recognized only in hindsight (Bonforte et al., 2008, 2009; Puglisi et al., 2008), many of us were convinced that the 2001 eruption had significantly destabilized the volcanic edifice, and that further flank eruptions would occur from now on in rapid succession.

On 24 September 2002, a shallow earthquake occurred on the northeast flank of Etna, along the upper portion of the Pernicana fault system, which had been very active during the 1980s but had not shown any seismic activity or significant displacement since 1988. The earthquake was accompanied by conspicuous ground rupturing along the fault, similar to numerous events between 1980 and 1988. A few weeks later, on 27 October 2002, a more pronounced movement along the fault heralded the onset of a new flank eruption, which affected both the south and northeast sides of Etna and destroyed numerous tourist facilities as well as forested areas. During a few days, a part of the northeastern flank moved by more than 2 m eastward; then the movement extended over an ever larger area to the southeast side of Etna, where earthquakes accompanying the displacement caused severe damage in several villages, such as Santa Venerina and Milo.

Top: The sector of Etna's eastern to southern flanks affected by flank instability and displacement is shown in pink. PFS = Pernicana fault system; VB = Valle del Bove; RN = Ripe della Naca; ZE = Zafferana Etnea; SV = Santa Venerina; TFS = Timpe fault system; AC = Acireale; TF = Trecastagni fault; R = Ragalna fault system. From Neri et al. (2004). Bottom: Distribution of earthquake epicenters accompanying the 2002 eruption and flank movement helped to distinguish several blocks (Blocks 1, 2 and 3) within the unstable sector, moving at different times and speeds. From Neri et al. (2005)

This immense mass movement, which was later revealed to have involved about 2000 cubic kilometers of rock (Walter et al., 2005), both of the volcanic pile and of the underlying sedimentary basement, was documented in extreme detail, thanks to improved monitoring equipment placed on the volcano a few years before. It could thus be established that the movement started at the Pernicana fault in the northwestern portion of the moving sector, and then extended both eastward - to the Ionian coast - and southward, affecting numerous fault systems cutting through the eastern and southeastern portions of the volcano. In the entire area, earthquakes were strongly felt and often caused damage, and cracks ripped through buildings and other constructions as well as roads.

Since the fall of 2002, the movement of Etna's eastern flank has continued, most of the time at somewhat reduced speed, but often with new accelerations accompanied by shallow earthquakes. Since 2004, the southern block in the unstable sector has started moving slowly southward. At the Pernicana fault, dramatic slip accompanied by earthquakes and rupturing of the ground surface has occurred several times in 2003 and 2004, and again in early April 2010. This all indicates that the volcano has not yet returned to a state of relative stability and equilibrium as before 2002 (or 2001, if we consider the eruption of that year a significant factor in destabilizing the volcano). As a matter of fact, the behavior of Etna has changed profoundly since 2001.

Fluctuations in Etna's eruptive behavior since 1600 AD, with marked variations in the frequency, style, and size (volume) of eruptions. The output rate was exceptionally high from about 1607 until 1669, when ten - most of them very large - flank eruptions occurred (see black vertical bars in the graph at the bottom of the figure) and up to 3 cubic kilometers of magma was erupted. Very low output and few flank eruptions are seen during the following ~100 years, until the 1760s when flank eruptions pick up in frequency and size. A marked acceleration in the activity of Etna is evident starting in the second half of the 20th century. Unpublished figure by Boris Behncke and Marco Neri

Eruptive cycles
If one looks at the historical record of Etna's eruptions, it becomes evident that the intervals between these events, as well as their characteristics (duration, location, volume, eruptive style) vary strongly. Unfortunately the record is complete only since the beginning of the 17th century, yet these past little more than 400 years show remarkable fluctuations in Etna's activity. The first 70 years of the 17th century showed unusually high levels of activity, with frequent summit activity and ten flank eruptions. Some of these flank eruptions lasted for years - the one of 1614-1624 being the longest flank eruption in the historical record of Etna - and produced large volumes of lava (1614-1624: about 1 km3, 1634-1638: about 200 million m3, 1646-1647: about 160 million m3, 1651-1653: about 450 million m3, 1669: about 650 million m3). A few of the flank eruptions were quite explosive and built large pyroclastic cones, like Monte Nero during the 1646-1647 eruption and Monti Rossi in 1669.

The last eruption in this series, in 1669, apparently emptied a shallow magma reservoir that had existed throughout the previous decades - evidence for such a reservoir lies in the presence of abundant up to centimeter-sized plagioclase feldspar crystals in the lavas of all eruptions from 1600 until 1669. The rounded shape and pale yellow color of these crystals has led the locals to call the lavas of this period "cicirara", which means something like "chickpea lava", because the crystals resemble chick peas! Due to a prolonged presence in a reservoir relatively close to the surface, the magma could cool and crystallize to the degree that plagioclase grew to the "chick pea" size crystals seen in the 17th century lavas. Further evidence for wholesale magma extraction from a shallow reservoir and a dramatic withdrawal of the magma column in the central conduit is the collapse of Etna's summit cone during the 1669 eruption (Corsaro et al., 1996).

After the 1669 eruption, Etna has never again produced "cicirara". Furthermore, the frequency and size of flank eruptions dropped sharply for about 100 years, with only three minor flank eruptions being recorded in 1689, 1702, and 1755. It seems that the magma reservoir that had fed the intense activity of the 17th century had disappeared, the feeding system of the volcano had been disrupted, and the mountain had become structurally stable. Much of the time, all magma that made it to the surface rose to the summit, where a new cone was constructed. Flank eruptions became frequent again from 1763 on, and for the next 100 years occurred about once per decade, with volumes of a few tens to rarely more than 100 million cubic meters per eruption.

Interestingly, throughout the 18th and the first half of the 19th centuries, there are no records of significant earthquakes in the unstable eastern sector of Etna as those of the 1980s and of 2002 and the following years. A powerful and destructive earthquake in 1818 near Acireale was probably caused by movement along a regional tectonic fault, not by movement of Etna's unstable flank.

Etna's unstable eastern to southern flank sector, and a selection of earthquakes presumably caused by movement of this unstable sector. Note that there have been many more earthquakes in this area during the period since 1865, when the first of these events took place. Unpublished figure by Boris Behncke

Then came the year 1865, which brought a large eruption on the northeast flank - the Monti Sartorius eruption - and soon after its end, a very localized, extremely shallow (close to the surface) earthquake on Etna's eastern flank, which devastated the village of Macchia di Giarre and killed about 70 people. Similar earthquakes have since then occurred at a recurrence rate of a few years, luckily rarely resulting in as many fatalities, but often causing significant damage and a few human deaths. Most, if not all, of these earthquakes are now known to be related to slippage, or movement, of Etna's unstable eastern to southern flank sectors.

At the same time, the intervals between flank eruptions have become systematically clustered into determined sequences, or parts of cycles. The first cycle started after the large 1865 flank eruption (and the first earthquake in modern time that can be with confidence attributed to flank displacement), initially with quiet emission of gas from the Central Crater and a few years later, mild activity within the Central Crater. From 1874 until 1892 there were five flank eruptions, which showed an overall increase in emitted volume in time, the latest - in 1892 - being the most voluminous (besides 120 million m3 this eruption also produced a significant amount of pyroclastics). This increase in the volume of flank eruptions was apparently the result of increasing structural instability of the volcano. Apparently the emission of a large volume of magma brought this cycle to a close, the volcano returned to relatively stable conditions, and a new cycle started, like the previous one, with a period of quiescence, followed by summit activity, which in turn was followed by a further series of flank eruptions. Four cycles of this type occurred between 1865 and 1993. The latest of these was longer than its predecessors - 42 years - and culminated in a series of no less than 13 flank eruptions, many of which were among the largest of the past 300 years. This cycle ended with the 472-days-long eruption that lasted from December 1991 until March 1993 and produced the greatest lava volume - about 250 million cubic meters - of any Etnean eruption since 1669.

Evolution of the 1952-1993 eruptive cycle at Etna, showing three main phases (Eruptive quiescence -> summit activity -> flank eruptions, ending with a particularly voluminous flank eruption). Unpublished figure by Boris Behncke and Marco Neri

Interestingly, there was very little seismic activity in Etna's unstable sector during the first two phases of this cycle, whereas they became more and more frequent during the third phase. Many episodes of accelerated flank displacement preceded flank eruptions by days to months, as in 1981, 1983, 1985, and 1989.

Etna's latest and ongoing cycle started after the end of the large 1991-1993 flank eruption. For two years, no eruptive activity occurred anywhere on the mountain. Then, in summer 1995, eruptive activity returned to the summit craters - first at the Bocca Nuova and then at the Northeast Crater; in 1996 and 1997 also the Southeast Crater and the Voragine joined the party (Allard et al., 2006). This period of summit eruptions continued until July 2001 and consisted of several long-lasting lava overflows and more than 150 episodes of violent Strombolian to sub-Plinian explosive activity, nearly always with copious lava emission. We called this exceptional period of activity "The Millennium Fireworks". Still more exciting fireworks came with the flank eruptions of 2001 and 2002-2003, and two more flank eruptions have occurred in 2004-2005 and 2008-2009, separated by a period of spectacular eruptions from the Southeast Crater in 2006-2008. These events are described in detail in the Bulletins of the Global Volcanism Network (scroll down the page to get to the more recent reports).

What should be noted is that since flank eruptions kicked in again in 2001, the unstable flank sector of Etna has moved at sometimes astonishing rates (up to several tens of centimeters in a few days in spring 2009), and seismic activity in this sector has been intense, including a series of rupturing events at the Pernicana fault as recently as April 2010. The volcano seems to be currently in the middle of an eruptive cycle, and it is likely that this will come to an end (and bring back the volcano to a state of temporary stability) only with a very large, voluminous flank eruption (Behncke and Neri, 2003a; Allard et al., 2006). From a scientific point of view this is rather exciting. From a human (and civil defense) point of view, these prospects are rather disconcerting and challenging.

So why does the flank of Etna move? It is now believed that much of the movement is caused by the pressure of magma accumulating within the volcano. As a matter of fact, much more magma enters into Etna's plumbing system than exits during eruptions. The quantity of this unerupted "excess" magma can be approximately calculated from the amounts of gas emitted from the volcano, in particular sulfur dioxide. It has thus been revealed (Spilliaert et al., 2005; Allard et al., 2006) that at least three-quarters of the magma that enter into the Etnean feeder system stay there, which leads to a constant volume increase. Where does all this magma go? There are certainly no empty spaces that can host this magma, so space must be created, and this is best done in pushing the volcano, both upwards (so that the volcano swells, or inflates), and sidewards, in whatever direction the side of the mountain gives way most easily. At Etna this is on the eastern, southeastern, and to a lesser degree, southern flanks, which are not buttressed by surrounding mountains as the northern and western flanks. It can be speculated that the more magma accumulates below the volcano, the more unstable it becomes, and this in turn facilitates the opening of fractures on the flanks, allowing magma to escape in flank eruptions. Possibly the presence of a large, relatively shallow magma reservoir during the 17th century led to a strong destabilization of the volcano, which thus had magma leaking through its open flanks on any given occasion, and in large volumes. A similar situation seems to be on the way to become established in recent decades - so no one would be really surprised to see Etna behave again like it did between 1600 and 1669, but once more, these are anything else than comforting prospects.

eklemetti Wed, 08/18/2010 - 00:14

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Very interesting.

I was just wondering, is a catastrophic flank failure at all likely?

Outstanding work Dr. Behncke! Thank you so much for publishing this to the impressed hobby-volcanologists!

"...much more magma enters into Etna's plumbing system than exits during eruptions."
This is, to me, a stunning revelation.
1. Do you believe that a massive failure of the southeastern slopes could take place, in a similar way as it did in Mt. St. Helen's?
2. Is ice accumulation, in winter, heavy enough to affect the stability of big fat Mamma Etna?
3. If you pick Etna and covers it with a huge Icecap (like in VatnajÃ¶kull, in Iceland) what would happen? Could we compare processes in Badarbunga system with Etna's?
It's getting more and more interesting and enlightening.
Thank you Boris.

@Gareth #1 and Renato Rio #3 - currently a catastrophic flank failure seems unlikely, because the stress on the eastern flank sector is released in numerous small slip episodes and nearly continuous, slow, aseismic creep. This is similar to the flank slip at Kilauea, and some publication (I admit I don't remember which one) recently proposed that basaltic volcanoes such as Kilauea, Etna, and Piton de la Fournaise are capable of accomodating their flank instability in numerous and frequent minor episodes rather than collapsing catastrophically. Obviously, catastrophic collapse does occur (it is well documented for the Hawaiian volcanoes and the Valle del Bove collapse at Etna seems pretty much ascertained by now) but more rarely.

Ice and snow accumulation are currently relatively minor at Etna - virtually all snow melts during the summer - but minor quantities of ice can be preserved under tephra if this is deposited on snow during the winter as in early 2000 and late 2002. The quantities of ice do not appear to be significant in affecting the volcano stability. However, a few thousand years ago this might have been different - a group of British scientists (Deeming, McGuire and Harrop) recently proposed that the Valle del Bove collapse was triggered by magma intrusion into water-saturated flanks during cooler and wetter weather conditions.

We know that Etna was covered with glaciers before the cataclysmic "Ellittico" eruptions 15,000 years ago. The presence of the glaciers certainly led to much more explosive volcanism than has occurred since then. However, this is an area of ongoing studies and much more needs to be revealed.

Boris,

I lived on Etna (in Nicolosi) from 1993 to 1996. I was able to witness it "re-awaken" from its slumber following the huge 1989-1993 lava eruptions. I used to go up to the fractures produced by the initial 1989 intrusions which cut the roadway to the ski area (as I remember!). At times, while I was at the fractures, the guardrails would abruptly begin to creak and pop, I believe due to further intrusion and spreading going-on beeath that area. so i had my own makeshift strainmeters! Upon returning to my home, following one particularly noisy/active visit to the fractures, the Northeat Crater erupted!
By the way,...another outstanding presentation of your knowledge of Etna volcanology!

Thank you Boris,especially for the information about flank stability. It never even crossed my mind that Catania on the sea may be in a fault/slip zone.

What an amazing volcano.

Stupendous.

Boris,

that was a fantastic presentation! I was watching some of what was going on, too, and that made it all the more interesting for me to read. I can hardly wait for the next installment! I can see why you chose to study Etna because it is a facinating mountain with some interesting seizmic zones along with the volcanic mechanisms.

From the illustration of Behncke and Neri (2003b) it looks like some fault blocks on the north-east area and I am wondering if it is part of the flank collapse or fault blocking.

I remember the quake that offset the roads and did so much damage and watched as the Piano de Lago disapeared. That was such a beautiful area before the eruption that covered so much of it. But there is beauty even in the lava flows just like the area around Mt. St. Helens and Mt. Lassen. It is amazing how things can recover so quickly and something else that I have found interesting is the fact that around Mt. St. Helens, there has been fossilization found already! I think that has blown the scientific world's mind. I will look forward to the day when some recovery will be evident in the Piano de Lago area. It will take a while, but I bet it will come back faster than we ever thought possible. Of course, it depends on Etna's activity. It could send more lava down that way.

Has there been any indication of an eruption taking place any time soon? Maybe you will be talking about that in your next post.

Thanks so much for taking the time to teach us about Etna and the complexities of the inner workings of a volcano not fully understood. Interesting stuff.

just a random thought ...

a large active sill type magma chamber extension in the E / SE would have a very high "lubricating" effect on the movement ? no ??

sort of like trying to walk on a sea of ball-bearings ???

I am in awe..I feel like saying "we are not worthy". Almost reluctant to ask what are probably rather silly questions, but:

Re the 'chick-pea' lavas: surely basalt magma held "in storage" for some time would first crystallise olivine? Are there olivine phenocrysts? Or did this mineral sink under gravity, so that somewhere in Etna's guts there are olivine cumulate lenses? (left after the bulk of that magma body had erupted)

Second: I read a while back (in a press story, so a dubious source) that recent Etna lavas had been found to contain amphibole, for the first time in many years. Is this so, and is it related to the recent changes in behaviour?

Third (more relevant to part 1, sorry); how does the historically active Campi Flegrei del Mar Sicilia (sp?) SW of Sicily fit into the plate-tectonic scheme for the Etna/Sicily area?

#10 @Mike Don
Your third question also came to my mind. I was curious to understand the tectonics under both Campi Flegrei Mar Sicilia and Pantelleria. The latter is explained as being "continental rifting" (!?)(SMI Global Volcanism Program)but they don't mention any correlation between the two volcanoes. Could Campi be a continuation of Calabric Arc? Could there be another segment of subducting oceanic lithosphere underneath? Or another "slab rollback" to the W? I have been doing some research over the web, but all I could find was this abstract from an article concerning the Lipari-Vulcano Volcanic System (LVVC):

"...the LVVC crustal structure and the evolution of the volcanism are consistent with those recognized in zones of transition from arc-related to rift volcanism. In addition, results of a preliminary mechanical analysis based on the available structural data indicate low values of the ratio between magmatic overpressure and tectonic stress. This suggests a passive mechanism of mantle upwelling. The mantle upwelling is due the post-collisional normal strikeâslip tectonics affecting the Aeolian Arc."

http://www.sciencedirect.com (link to big to be pasted)

Since the LVVC is further NE I don't know if has any relation to Campi and Pantelleria, both only 70 km apart.
When Boris said "the geodynamic setting of Etna is a bit complicated" he really meant it.
Any clues, Boris?

@Mike: I also found a very interesting book on the subject through Google Books:
"Postcollisional tectonics and magmatism in Mediterranean region and Asia, by Yildirim Dilek,Spyros Pavlides (you can read parts of it):
Here's a transcript:
"These features collectively suggest that the fault pattern observed in the Sicily channel may result from coexistent deformation regimes, with NE-SW-directed extension superimposed on the subduction-related NW-SE-directed compression in the Maghrebides (?), Sicily and the Apenines. The case history of the Sicily channel indicates that continental and extensional processes can overlap in the same area. Moreover, the coexistence in this central Mediterranean area of two deformational settings suggests that plate boundaries are passive features rather than the driving mechanisms of plate tectonics."
Isn't that awesome?

I'm still trying to get my head around just how big this volcano is.

http://i34.tinypic.com/2n9jl34.png

@Lurking
Fantastic plot! You can almost see the magma pushing up through the "slab-rollback-created-window". And yes. It is huge. Good job!
I suggest that everyone tried some Google-earthing over Sicily. And also over Pantelleria. Don't miss the pictures attached - you can see the most extraordinary rock formations near the southern edge of the island.
And then you all understand why Boris is so happy in this geological paradise.

Okay... I have more faith in these profile quake plots.

View North

http://i33.tinypic.com/8ys4dz.png

View East

http://i38.tinypic.com/2mq0pow.png

Note how the quakes tend to veer off to the East as they get shallower. (compare the two views)

View North is one degree across, View East is 0.5 degrees across.

#15 You mean, like in an ascending helical? Interesting...

Fantastic article, Boris, thanks! When will you write the definitive book on Etna?

@Lucky #13: what strikes you as odd about the topology?

Other Etna data graphs of interest:

1. Using the Volume vs Time chart, if one goes to the Wikipedia Little Ice Age entry and captures the past portion of the temperature plot (1600-2004) and superimposes a semi-transparent image over the TvV chart, very nice correlation may be found in the rate change over time.

2. Using the 'example of a cycle' chart, and superimposing upon it a portion of the 'Global Temperature Record' (also a wikipedia graphic), again, we see an interesting correlation between phases and temperature.

So what is going on here? We got a hint, in Boris' comment above, that one of the phases of activity *may* be correlated to Ice Age recession of Etna glaciers at existed during the Dryas period of icecap recession.

We think temperature glacier rebound, centered just below Switzerland where large icecap fragments once existed and glacier recession is much in evidence, and change in Mediterranean sea level during recent hemispheric cooling (LIA, within the last 400 years) might be factors at work in 'loading' aesthnosphere window flow to the magma chamber, with corresponding flank fissure periods during record warm periods.

If the window aperture were relatively narrow, the adjacent plate flexure may explain sensitivity to continental isotactic shift and through changes in sea floor pressure.

Conjecture of course, but interesting correlations nonetheless. If this were true, it might provide a basis for modeling past events and predicting activity cycles as a function of climate and sea-level change.

I wouldn't exactly call that helical. A bend, yes... but I don't think a helix from that small amount of data. (2009 to like... two days ago)

I did see a helix pattern in some of the EyjafjallajÃ¶kull quakes, but I can't tell you what it means... other than being an interesting fracture pattern.

#19 Yes, I recall having seen that pattern elsewhere too, that's why I mentioned it. Maybe there isn't enough length for a full helix to develop, or maybe magma isn't fluid enough to let it go, but it looks like, for my amateur eyes, after so many plots of crust and mantle features, that there's always this twisted shape in most instances, whatever they be, faults, quakes or rising magma. Comes to my mind another discussion upon its vortex-like behavior. (??!!!)

That's the idea of the blog!
Learning more and more. I hope in the future an article of the different types of volcanic quakes (VT, LP, HB, etc.) to know what they mean, not only the abreviations, but the physical interpretation.

Boris,

Thanks Boris, I'm looking forward to part 3. I was on Etna in october 2009 and returned in july this year, I never realized that Etna is such a huge volcano. The pit at the foot of South-East crater was intermittently steaming vigorously. http://picasaweb.google.nl/ptibben/EtnaSicily#5507022110941199874

@Renato Rio, I did my master's project on Pantelleria last year. It is in an extensional setting despite the overall tectonics being compressional, which surprised me to begin with. GPS studies show that the western tip of Sicily is moving slightly more eastwards than Tunisia, leading to E-W stretching in the Sicily Channel. Paleomag also shows Sicily has rotated clockwise. Why this should be happening, though, I never did find out; I was measuring CO2 output so it wasn't really relevant. Boris may know more, he did write a paper on it, after all...

After the past week of non-stop earthquakes around the world this quiet trend that has been going on for the past few days almost feels like the calm before the storm.

Thanks again, Boris. You've given us such an amazing resource. Non-scientists almost never have access to graphics like these, with descriptions and analyses written in non-scientific English. I'll come back to this again and again.

@24 Haven't really noticed a quiet trend, then again haven't really paid attention. However I have noticed the sun's activity has quietened down from what is was the last few months. I'm not making any connections here just an observation.

@26 Chris, Did you see the solar eruption yesterday that happened on the far side of the sun, it was a blast which produced a C4-class solar flare and hurled a bright coronal mass ejection (CME) over the sun's western limb?

http://www.spaceweather.com/swpod2010/18aug10/cme_c2_512.gif?PHPSESSID=…

I look at the solar weather site too, it is possible that the magnetic storms could effect more that we think.

Thank you, Boris! My knowledge is by far not good enough to understand everything but I still very much enjoy reading your great texts! Keep it coming, please :-).

Renato 11/12: Thanks for these references. it looks like the western end of Sicily is as complicated as the east (and thanks for that to Gareth too) I wonder if the CFdMS activity has some relation to that curious kink in the plate margin down the west of Sicily (diagram from Boris' link to Highly Allocthonous) We really need Boris on this one.

An ability to visualise in three dimensions is vital for geologists..it's something I'll have to re-learn :o(

Gareth: more please sometime on Pantelleria, it's one of those forgotten volcanoes that no-one ever mentions

@Gareth:
Thank you for the update. It is becoming clearer now.
@Mike don:
Thanks for bringing up the question. It was a fascinating piece of research.

@23, Gareth: this citation answers your question on the clockwise rotation you mentioned in your comment.

Structural evidence for Neogene rotations in the eastern Sicilian fold and thrust belt. Monaco and DiGuidi (2006)
J Struct. Geol. 28(4):561-574.

>From a geodynamic point of view, the Neogene clockwise rotation in the eastern Sicily fold and thrust belt is related to the regional framework of the AfricaâEurope convergence.

Historical Etna flow diagram from Dr. Behncke's post draped on Google Earth (3D) with roadways enabled. 3 x vertical exaggeration.

http://i37.tinypic.com/8ygcvq.png

@27 R.Hurst Yes I saw that. Pretty cool stuff. Seeing the sun build up to some high activity for the last few months and now showing some low activity again is a bit of a let down, almost anticlimatic. I was hyped up over all the sun activity then I read about 3 X-class solar flares that were directed at earth in 2005, I think it was, and really had no adverse effects besides some nice aurora's further south. Also I'm waiting to see if we get more swarms at yellowstone in the dec/jan time frame.... sorry to diverge from the Etna topic at hand.

@33Chris, A great site to see a dozen pics of the real-time sun each with a different filter is

http://www.solarmonitor.org/index.php

I made a mistake posting the sun comment on the Etna topic, I was aiming for the summer thread #2, sorry everyone.

I really enjoy reading about Etna Boris, I brought up this page at home and my 14 year old son saw your write-up. On Discovery channel last month we watched a show on the most dangerous volcanoes in the world and Mt.Etna was featured, lets just say that he was very impressed, you are a great writer Boris.

Lurking, master of charts could you do on on the activity at VatnajÃ¶kull?

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GVP Weekly Volcanic Activity Report for July 28-August 3, 2010

eklemetti — Thu, 05 Aug 2010 09:54:33 +0000

GVP Weekly Volcanic Activity Report for July 28-August 3, 2010

A new Weekly Volcanic Activity Report from the Smithsonian and USGS Global Volcanism Program!

Highlights from this week's report include:

Things are getting a little noisy in Colombia. I mentioned a few weeks ago about a possible explosion at Nevado del Ruiz. Now we have reports of increased seismicity under nearby Cerro MachÃn and ash plumes from Nevado del Huila. After a few centuries of relative quiet, it looks like the volcanoes of the Colombian Andes are looking more lively.
Also in South America, a gas plume was spotted at Chile's Planchon-Peteroa. This is the second time this year that increased gas emissions have been noted at the volcano that hasn't erupted since 1998.
Shiveluch on the Kamchatka Peninsula in Russia continues to rumble - ash plumes were produced from pyroclastic flows and steam-and-gas plumes reaching 4 km / ~13,100 feet were spotted as well.

eklemetti Thu, 08/05/2010 - 05:54

More activity in Wyoming just south of Yellowstone this morning, bringing the current EQ list to:
4.22010/08/05 14:59:28 43.646-110.416 5.0 34 km ( 21 mi) ENE of Teton Village, WY
4.82010/08/05 00:04:17 43.585-110.440 5.0 29 km ( 18 mi) ENE of Jackson, WY
3.02010/08/05 00:04:03 43.585-110.438 5.0 29 km ( 18 mi) ENE of Jackson, WY

though I can plainly see many aftershocks on this webicorder:
http://quake.utah.edu/helicorder/moow_webi_1d.htm
(for yesterday)

and this one for today:
http://quake.utah.edu/helicorder/moow_webi.htm

But there are still no updates to the earthquake map aside from the three larger earthquakes. What's up, USGS?

Hi Jen,

There may be no official statements from the USGS yet, but there is a bit of chatter on a local blog at:

http://www.jhunderground.com/2010/08/05/quake-watch-along-teton-fault/

I visited the place last summer, really interesting geology.

You can add another 3.2 at Wyoming @ 17:45 UTC. I can expect we'll see another swarm this winter.

The rumblings in Columbia, I'm wondering, if they're the effects of all the recent quakes in Chile.

Just came across the photo collection of Owen K. N. (as it seems he's a geologist) on Flickr, which has some outrageously spectacular aerial views of Bezymianny and Kliuchevskoi (or Klyuchevskoy) taken late July:
www.flickr.com/search/?q=klyuchevskoy&w=35670622%40N06&ss=1&s=rec
What strikes me most is the large cone that has grown within, and is now practically completely filling, the summit crater of Kliuchevskoi as seen in particular here:
www.flickr.com/photos/oneill244/4864468767/
The outline of the old crater rim is still marked by small knobs on both sides of the new cone.
Owen had the privilege to witness, from a safe distance, pyroclastic flows descending the southern or southwestern flank of Kliuchevskoi:
www.flickr.com/photos/oneill244/4864932936/
There are also spectacular views of a lava flow extruded from Bezymianny after its latest explosive eruption in May this year, like this:
www.flickr.com/photos/oneill244/4865084090/

Boris, just saw you on tv! Th Etna flank collapse program. Nice to put a face to a name!

Amazing pics, Boris, thanks a lot!

What Renato said - wish I'd been there; not only the volcanism, but also the fauna seems to be fascinating.

When I saw the equipment pics, I thought, "That must be KVERT stuff." ;)

Thanks Boris. I never thought a volcano could rebuild itself so quickly. What would be the mechanism? Super thick rhyolite? (ie so thick that it can't move?

Yesterday, I wondered if the August 4-5 strong solar storm might have any effect on magma flow on earth and therefore on earthquake activity. Or perhaps there may be more simple interactions between strong electro-magnetic (E-M) disturbances and the Earth's crust - which might result in tectonic movements and earthquakes.

I found that there were five magnitude 6.0 or greater (M6+) earthquakes during the solar storm's strong E-M disturbances of Earth's atmosphere and space environment. During the eight days from July 30 to August 6, there were only two other magnitude 6.0 or greater earthquakes, so there was a clear anomalously sharp increase in occurrence during the strong solar storm.

Note: Sometimes multiple numbers of M6+ earthquakes will be recorded within minutes or hours because they are at the same approximate location and part of the same tectonic event. But the five M6+ earthquakes recorded during the solar storm were not at the same location, but rather widely dispersed in locations around the pacific ocean.

This is only one correlation of a solar storm's E-M disturbances to the Earth's seismic activity, so no firm conclusions can be drawn. But the fact of the anomalously sharp jump in M6+ earthquake occurrences during the 33 hours of the solar storm's E-M disturbances upon Earth is very intriguing and should prompt for further study.

Here is the data:

----------------------------------------
E-M Anomaly In Earth's Space Environment:
----------------------------------------
Proton flux unusually high: Aug 3, 18:00 UTC to Aug 4, 06:00 UTC = 12 hours duration
E-M disturbance very high: Aug 3: 18:00 UTC to Aug 5, 03:00 UTC = 33 hours duration

Source: http://www.swpc.noaa.gov/ftpmenu/plots/satenv.html

----------------------------------------
Quakes >= Mag 6.0
Eight Days: Jul 30, 2010 to Aug 6, 2010
----------------------------------------
* 2010/08/05 03:00:00 SPACE E-M ANOMOLY ENDS

6.0 2010/08/04 23:48:03 45.964 153.216 33.6 EAST OF THE KURIL ISLANDS
7.0 2010/08/04 22:01:44 -5.768 150.776 44.0 NEW BRITAIN REGION, PAPUA NEW GUINEA
6.4 2010/08/04 12:58:25 51.426 -178.607 27.0 ANDREANOF ISLANDS, ALEUTIAN IS., ALASKA
6.4 2010/08/04 07:15:33 -5.521 146.793 213.6 EASTERN NEW GUINEA REG, PAPUA NEW GUINEA
6.0 2010/08/04 04:46:22 -26.953 -177.148 23.7 SOUTH OF THE FIJI ISLANDS

* 2010/08/03 18:00:00 SPACE E-M ANOMOLY BEGINS

6.3 2010/08/03 12:08:27 1.243 126.277 42.8 MOLUCCA SEA
6.3 2010/07/30 03:56:13 52.461 159.902 18.6 OFF THE EAST COAST OF KAMCHATKA, RUSSIA

Source: http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/quakes_all.php

William Boston

@ Chris - I would doubt there is any connection between volcanic activity in Colombia and the seismicity earlier this year in Chile.

If Cerro Machin does erupt it could produce some very impressive and dangerous pyroclastic flows. The quote below is from
http://www.volcano.si.edu/world/volcano.cfm?vnum=1501-04=

"Voluminous pyroclastic flows traveled up to 40 km from the volcano during eruptions in the mid-to-late Holocene perhaps associated with formation of the caldera."

We are in the Holocene now correct? So the pyroclastic flows may not have happened in the extreme distant past. Maybe they haven't been able to study this volcano as well as they have studied many volcanoes in the US and that is why the dating of the pyroclastic flows isn't as precise as some of us would like.

Now what are the odds that this increased seismic activity under Cerro Machin does not indicate that there will be an eruption there in the next few decades? This is where the experience of volcanologists is helpful in reading the physical signals given off by a long dormant volcano.

so informative, thanks to tell us.

(Late) Wednesday Whatzits: Hawaiian lava flows, more Katla mongering and a possible eruption at Ruiz?

eklemetti — Wed, 21 Jul 2010 15:54:13 +0000

(Late) Wednesday Whatzits: Hawaiian lava flows, more Katla mongering and a possible eruption at Ruiz?

Kilauea lavas on the move near Kalapana. Image taken July 17, courtesy of the Hawaiian Volcano Observatory.

Some news over the last few days:

The lava flows from Kilauea are moving with a vengeance right now, damaging roads and heading for some structures. The lava flows near Kalapana have moved almost 200 meters since Sunday, closing within 100 yards of homes in the area. The lava is moving to the east along Highway 130 and 137 - and tourists are making it difficult to get around as they park to watch the lava - upwards of 2,000 people! A number of people (and dogs) have had to be evacuated as the lava slowly flows into Kalapana - last inundated with lava 21 years ago. It is a busy summer for the Hawaiian volcano, thats for sure.
I would also like to derail some of this continued Katla-mongering, this time over at Cosmic Variance. This is not to say we shouldn't watch Katla, but all these swarms are still (1) too small; (2) too shallow and; (3) too short. I would place a safe bet that there are many more volcanoes worldwide that are much closer to eruption than Katla - and the connection between EyjafjallajÃ¶kull and Katla is tenuous at best. So relax!
Now, when was the last time you saw a Smithsonian/USGS GVP Weekly Volcanic Report with so little new activity? It is indeed a quiet summer for volcanoes - or maybe this is just in comparison to the Iceland furor of earlier this year. However, the latest report does talk about increasing signs that Gorely may be headed for an eruption and a possible eruption at Nevado del Ruiz in Colombia! There are few details of this event beyond a seismic signal that suggests an explosion, but no ash was seen after the clouds allowed for direct observation. I'll be keeping a close eye on this if Ruiz is becoming active after 20 years of quiet.
Finally, be sure to check out the excellent article on Yellowstone over at the new home of Highly Allochthonous. It is a great primer for folks who want to know why the caldera is there and see some of the great volcanic features - but I would say that the Hawaii-Emporer Seamount chain is Yellowstone's evil twin (rather than vice versa as Anne and Chris say) - Yellowstone is just cleaning up all those mountains that crumpled North America!

eklemetti Wed, 07/21/2010 - 11:54

Hi Erik,

Glad you have been able to post more as I know you are writing like mad to get the reports done.

I have thought it has been rather quiet on the volcano front for a while, but you never know when things will get rather noisy. That flow in Hawaii is wrecking havoc to some people and it is looking like some are going to loose their homes. Not a fun thing at all.

I'm looking forward to your posts when you can get to it on your research trip. I have never been in that area and I want to know what you have found. I know I am not the only one!

Cheers

Katla is indeed quiet at the moment. So quiet that GPS data is stable and not much happening there at the moment.

I am expecting a eruption at Katla in 5+ years time. But earthquake swarms are due to happen more often inside the caldera when Katla goes closer to a eruption. Currently the earthquakes that are happening are summer/autumn earthquakes due the ice-cap being lighter in the summer then in winter. The current area is known for high earthquake activity, and I have recorded earthquakes from there since I setup my Hekla seismometer in 2008 (soon after the Mw6.3 earthquake in the SISZ fracture area).

So far it is all quiet. But that might change, but with Katla not without at least one week warning I would think.

S'okay! Back to the Turrialba webcam! I'll nix Katla from the hitlist and add it to the list with the prefix s- added to it.

Can anybody link me the youtube video shot by the tourists in (unk. central american country) that were standing on the summit when it cut loose with a phreatic eruption?

For Chris from the other thread just in case he missed it.

By request.

Plot is the number of quakes worldwide in 7 day and 30 day bins, USGS data source. Depth 100 to 900 km, Mag 4.5 and greater.

Oops... here's the plot.

http://i27.tinypic.com/10s4xti.png

If anyone wants to see some real volcanic action just watch the Sakurajima webcam for awhile. Especially when the volcano seems to have gone quiet - you may be in for a real treat before too long. http://webcam-svo2.pr.kyoto-u.ac.jp/local/camera.html

@Kver -
Not a video but a series of stills from Pacaya, showing tourists almost getting it: http://www.youtube.com/watch?v=qsy5yuyN_aE

This is a video: http://www.youtube.com/watch?v=WlTJLbMRKm0&NR=1

As is this: http://vimeo.com/3376312

"Never underestimate the power of human stupidity."

@Kver -

Ah, the first attempt with live URLs got stuck, let's try it without any obvious...

Not a video but a series of stills from Pacaya, showing tourists almost getting it: www.youtube.com/watch?v=qsy5yuyN_aE

This is a video: www.youtube.com/watch?v=WlTJLbMRKm0&NR=1

As is this: vimeo.com/3376312

"Never underestimate the power of human stupidity."

Isn't the Hawaii-Emperor Seamount chain a LOT older than the Yellowstone hotspot? Maybe a better 'family relationship' would be Hawaii as Yellowstone's evil grandpa...... ;-)

@mike [6] -
Good advice. I watched it for a while and caught a spectacular explosion. After the dust settles, it will be interesting to see if there was more than just an explosion.

Something seems to be shifting under Fox Island, Alaska. There are a lot of large earthquakes at 10km depth.

Sunrise in South America, and it looks like a gorgeous day.

Cotopaxi, Turrialba, and Nevado del Huila looking really clear.

Further to #11, Nevado del Huila is spectacular, sunlit bright red clouds flowing off the summit with sky still almost black
http://intranet.ingeominas.gov.co/webcam/popayan/webcam_Huila.jpg

A 3.8 at Long Valley last night, and the earthquake swarm inside the caldera is pretty active today.

http://earthquake.usgs.gov/earthquakes/recenteqsus/Maps/special/Long_Va…

So far they all have about the same (8 KM) depth.

OT a bit. There currently is a swarm going on in Long Valley. There have been two 3+ (largest is 3.8) quakes and they are about 1.5km SW from Whitmore Hot Springs and about .5km from the SE end of the Mammoth-June Lakes Airport. It is close to an intersection of US 395 and the road that goes to the hot springs. I am not sure, but Hot Creek could be involved (they did not name the creek on the map except to say "Creek") because the quakes seem to be right along the creek.

The observatory is only posting updates once a week so for the moment there isn't any info about it. I do know that it is techtonic, most likely, as the depth of the quakes is around 5km avg. and there are a lot of faults in the area.

If I find out any more info, I will be sure to post it. Of course, there are those of you who will probably find out more quickly than I can. :-)

We will see how long this one goes.

Ooops! I meant to say 5mile, not 5km. LOL

I find the LVO updates frustrating. Lately they are always one paragraph with no mention of deformation, gas, or hydrology. These are the things we can't see just from looking at the earthquake lists, it would be nice if they'd at least throw in a sentence about them as they used to, particularly since the tiltmeter and magnetometer closest to the current swarm don't show any data on the website.

Jen,
They probably changed who is writing the updates at LVO. They may have even had to have sent people to Hawaii to help out with activity there in the past year, I don't know.
The activity there in 1980 and the late 90s has been attributed to dike intrusion. I believe the most likely scenario for the next eruption there is such a dike reaching the surface.
Anyone out there plugged in to happenings at LVO?

@ Ekoh and Jen, I don't like the way they are doing the reports either. I have written to them to see if I can get an answer, but I bet they won't very quickly if they do. We can try the USGS at Berkely to see if anyone there will give us an answer. I was communicating with Steve Walter, but he quit answering my emails so I figured I was bothering him too much. I know they went though, but no answer from him. Anyway that is about all I can say at the moment about it. I think they should at least write up something when a swarm takes place. I mean it is close to the airport and right by the road going to Whitmore Springs and also the creek. Almost right on the creek.

Oh well...

Well, lo and behold, I did get an answer of sorts from Long Valley. It is an automated message telling me that Dina Y. Venezky is out of the office until Friday. She was presenting at the Google Teacher Institute.

So maybe we will hear something then as this is the only message I will get until tomorrow.

On an unrelated topic:

A grad student at MIT came up with a new theory on the fluid dynamics within Stromboli volcano. Apparently the old theory of large gas bubble popping and causing the frequent eruptions didn't use realistic values for the viscosity and surface tension of lava....

Science in action, we'll see if this new approach will find broader acceptance or not.

You can read a short article at:

http://www.laboratoryequipment.com/news-fluid-dynamics-kill-volcano-the…

>I find the LVO updates frustrating. Lately they are always one paragraph with no mention of deformation, gas, or hydrology.

The updates may be brief, but it's not like you can't quickly access the data for recent trends.

The LVO website is loaded with information and is one of the better organized and annotated USGS-VO electronic data centers. The only monitoring data link that sucked was gas, although do provide a recent trend synopsis.

They even have QuickLinks for accessing data.

The only monitoring station data that looks a bit odd is Fossil.

I did some checking on the LVO site and I found out there is a geothermal plant in the vacinity so the quakes may be from that activity. I did not see just where the quakes are in relation to the plant as I had to make a guess on that, but I don't think they are too far apart. The site has some good information on the effects of quakes on the hydrology of the area and also has info on the plant. Here is part of what they say:

"Wells drilled on the southwest side of the resurgent dome at Casa Diablo tap into the caldera's hydrothermal system by pumping hot water (170Â°C) to supply three hydrothermal power plants that generate about 40 megawatts of electricity. Using a binary technology, a secondary fluid (isobutane) is heated by the pressurized geothermal water, vaporized, and then run through the generating turbines. Cooled geothermal water is reinjected underground.

The hydrologic monitoring program has detected changes in the hydrologic system caused by geothermal development and variations in precipitation and recharge. For example, we have delineated decreases in thermal-spring discharge at sites within about 5 km to the east of Casa Diablo that are caused by subsurface pressure declines at the geothermal well field. No changes have as yet been detected in the springs in Hot Creek Gorge. There has also been an increase in steam discharge at Casa Diablo and sites farther west due to increased boiling in the geothermal reservoir caused by geothermal production."

Link: volcanoes.usgs.gov/ivo/activity/monitoring/hydrology/intex.php

don't use www.

Thanks Passerby for steering me in that direction.

@Diane -
Copy/paste, pls...
http://volcanoes.usgs.gov/lvo/activity/monitoring/hydrology/index.php
works

@21 Passerby, the other monitoring info is there, but not included in the updates, which I think is what the informed and interested layperson would be looking for.

In any case, it looks like just a tectonic quake and aftershocks. No change in depth, gas emission or deformation, all things that would occur if magma was on the move. The fact that its in the caldera doesn't mean too much, since future eruptions need not occur there, in fact many of the past events did not.
Long Valley would be an interesting topic for Erik sometime if things are slow.

@Lurking: I think we need a graph for Grimsey. Pretty interesting swarm going on there.

@mike [6] Thanks for the tip re Sakurajima; clicked on the link and was rewarded with quite a show ( about 3:55pm MST )

A very nice swarm in the TjÃ¶rnes Fracture Zone - 70+ quakes ranging up to M2.8 and from 1km to 25km deep, probably tectonic(?). Those of you who missed the lead up to EyjafjallajÃ¶kull, take a look because this is the kind of swarms you'd expect if Katla was up to anything! But please note what Erik said about EQs starting deep and moving upwards with time - Lady E kept going for almost two months with up to 350+ quakes over the 48-hour period displayed by Iceland Met.

//en.vedur.is/earthquakes-and-volcanism/earthquakes/tjornes-small/

*squint* The Longterm Trend statement, right underneath the weekly report, reports on seismic, deformation, gas data. There has been very little change for quite some time, with the exception of the Fossil site.

The weekly report hasn't mentioned deformation and gas data for many moons now. Years. The weekly report covers automated seismic detection system reports EQ number, and LVO staff add depth data for larger quakes above the monitoring threshold, as well manually reported quakes and nearby activity (sourced from an additional 20 stations within 50-km of the caldera boundary).

The only item that has been missing from recent weekly LVO reports is the monotonic recitation:

'The Long Valley Observatory (LVO) monitors and studies earthquakes, ground deformation, degassing, and other types of geologic unrest in and around the Long Valley Caldera. The 15 by 30 km Long Valley Caldera was formed during an eruption 760,000 years ago and is located 20 km south of Mono Lake along the east side of the Sierra Nevada in east-central California. There have been multiple smaller eruptions since the caldera-forming eruption with the most recent occurring 250 years ago in Mono Lake at the north end of Mono-Inyo Craters volcanic chain. LVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.'

USGS staff monitor this blog. The informical wording can be added to the weekly reporting page for public peace of mind.

Agreed on the suitability Long Valley for discussion topic.

'Future eruptions are more likely to occur somewhere along the Mono-Inyo Craters volcanic chain than from the resurgent dome or south moat area within the caldera. '

@Kulsi #24, Sorry about that. The reason I didn't post it as a copy and paste is because 1) I tried it and it didn't work, and 2) I didn't think it would post if I typed it in because some have had trouble posting links. Next time I will type or paste the whole thing and hope it gets posted as one you can click on.

@Passerby, I just wish LVO would go back to daily or at least twice/week on their updates. However, I can see why they might not do that if there isn't much going on in the first place. Anyway, I will see if I get any response tomorrow on the email I sent them. I think it is techtonic and I also think there may be a connection to the geothermal plant because of the close proximity. I don't think it means anything other than that.

I thought it was interesting because it is happening in an area I have not seen before since I have been monitoring Long Valley. I have seen them on Mammoth Mt. and those could have been techtonic also because there are two faults up there. I have also seen swarms outside of Long Valley over in the Adobe Hills in NV. Those are not that uncommon and are techtonic.

I would like for Erik to do a blurb on Long Valley because it is a very interesting place. I have been there and I would love to go back and do some more nosing around at the geology in more depth. I have been to one of the Inyo Craters and that was interesting to look at. Lookout Mt. is an obsidian dome and there is another one called Obsidian Dome and these domes are not small by any means. Cool place to study volcanic geology.

Err... okay

17 - 22 July

Looking North:
http://i30.tinypic.com/29v0952.png

Looking East:
http://i30.tinypic.com/jh98xx.png

I might get to Long Valley later this evening. Still canning and working on a beer.

Long Valley Area

Quakes 7/15 - 7/22 Quake Plot

View North
http://i25.tinypic.com/33nu9si.png

View East
http://i31.tinypic.com/2hrnwr6.png

This is more attention than my griping probably deserves, but this is the kind of thing I mean, from May 28, 2010. "We have detected no ground deformation associated with this swarm and see no other evidence that it might be associated with a magmatic intrusion. Low-level earthquake activity elsewhere in the region continued with little change from the past several weeks. "

It's nice to get an update on these things, because honestly I can't make any sense out of most of the monitoring data links. I'm just interested in the area and like to know what's going on. YVO usually includes a ground deformation summary in their updates, I guess that's what I was thinking of, I hadn't noticed that it wasn't included in the LVO updates until recently. (Probably because there wasn't as much going on there.)

It's instructive to spool through several years of weekly reports, as it affords a baseline that accentuates the increased activity this year. Still not enough, however, to warrant more than weekly updates.

As usual, the USGS has useful background reading, a history of Inyo Craters:

http://volcanoes.usgs.gov/lvo/about/inyo/history.php

and another USGS classic: GEOLOGIC MAP OF LONG VALLEY CALDERA, MONO-INYO CRATERS VOLCANIC CHAIN, AND VICINITY, EASTERN CALIFORNIA (Baily 1989)
pubs.usgs.gov/dds/dds-81/GeologicalMaps/ScannedMap/sheet2b.pdf

Detailed explanatory text to go with the scanned map/figures
www.joshfeinberg.org/Geo3890/Schedule_files
/Bailey_1989_text.pdf

(part 2a is Mono Lake, we'll throw it in here for completeness sake)
pubs.usgs.gov/dds/dds-81/GeologicalMaps/ScannedMap/sheet2a.pdf

@Lurking: Amazing, as always, you plot those quakes giving us a dimension of what's taking place underneath. Thanks a lot.

@ any seismologists/other experts who might read this:

What possible explanations are there for such stacked earthquake sequences?

I can get my head around Coulomb stress transfer and migration of seismic activity along a stressed fault but these stacks "look" more like dikes and intrusions. Could they however also be stress transfer along a vertical plane, such as you would get in a graben? Somehow they look to neat to me for that.

@Lurking, Passerby. ... thanks! great stuff!

Several months ago, we spent time examining Tjornes. Similar plots were superimposed onto graphics from informative explanatory articles, and recent bursts of activity from this year were found to line up with historical EQ series rather precisely, but with a evidence of further extensional activity (attributed to either geothermal or magmetic intrusion at depth) between faults. The faults trended in a particular geometry horizontally and also vertically.

so... you're saying intrusion at depth pops open the overlying strata in a pattern that creates vertical (and horizontal) sequences?

#39 There's evidence of past submarine eruptions at the region. Could it be the case? EQs don't seem to get to a halt.

Garry Hayes at Geotripper has these to posts on Long Valley/owens lake/ mammoth lakes

geotripper.blogspot.com/2010/04/my-first-day-of-summer.html

geotripper.blogspot.com/2010/05/who-knew-smokey-bear-story-behind-story.html

geotripper.blogspot.com/2009/10/keeler-earthquake-swarm.html

He references this article "A field trip to Owens Valley/Mammoth Lakes
http://geology.csupomona.edu/docs/sierra.html

Present EQ series patterns match geographically *tightly* to previous history of miniquakes on segmental faults, with newer quake series extending the end of the segment (Grimsey Lineament and Husavik-Flatey Fault), with a spattering of quakes roughly parallel to the two primary dense clusters (tympanic).

Papers (open access docs)

RECENT AND PRESENT-DAY TECTONICS NEAR A HOT SPOT: THE
TRANSFORM ZONES OF ICELAND. F. Bergerat, J. Angelier, C. Homberg, S. Garcia, S. Verrier and M. Bellou (2010)

TjÃ¶rnes fracture zone. New and old seismic evidence for the link between the North Iceland Rift Zone and the Mid-Atlantic Ridge.

has Tjornes microquake data 1994-2005, see first paper
Fig 1. was overlayed with May 27-30 EQs from IMO map.
Fig 2 has historical swarms 1994-2005

Excellent explanation of the tectonics:
Fig 3a from Garcia paper, second paper.

Off to bed.

@ passerby, juicy paper!! beachballs and all. Thanks!

damn, second paper seems to have been taken down by IMO

TjÃ¶rnes fracture zone. New and old seismic evidence for the link between the North Iceland Rift Zone and the Mid-Atlantic Ridge.

parclair, thanks for the link to "A field trip to Owens Valley/Mammoth Lakes." Boy, does that bring back memories of the many trips my family took up and down Highway 395 east of the Sierras in my youth. So many familiar, but nearly-forgotten place names. At different times we camped at Rock Creek and at Mammoth Mountain (before there was a ski area), stayed at a ranch in the Alabama Hills, hiked the Mt. Whitney Trail (when I was only 4 or 5), visited so MANY fascinating geologic sites over the years. 40 years ago, I picked up a volcanic bomb at the Red Hill cinder cone in the Coso volcanic field. It has served as a hefty bookend in my den ever since. Good times.

Friday
23.07.2010 08:38:23 66.650 -17.946 22.5 km4.190.0112.4 km NNE of GrÃmsey
Two 4.1 quakes!

Friday
23.07.2010 08:38:23 66.656 -17.997 13.4 km4.190.0412.7 km N of GrÃmsey

@ Renato, now we're talking. That's a good swarm going on there. Most between 8 and 12 km depth with a suspiciously high number of M1.1 quakes at 100 m depth (which obviously need checking!)

Ahh.. found it. I lost track of which thread was talking about GrÃmsey.

This is a cross post.

GrÃmsey Perspective View
i25.tinypic.com/33yqqmv.png

Time vs Depth
i25.tinypic.com/2ujjspc.png

Time vs Depth for the last batch of activity (End of May)
i28.tinypic.com/1z67dpj.png

@Lurking: It looks pretty much like rising magma to me, what do you say?

EQ 3.5 off north shore, cal. near SF earthquake.usgs.gov/earthquakes/recenteqsus/Quakes/nc71436076.html#details

There is internet chatter that the 3.5 off California coast is a pre-quake and that a 6 or 7 pointer will hit by Tuesday. What do you all think of that idea or is it just chatter?

@Stigger: there will be a 6 or 7 quake in California, but probably not by Tuesday. All scientific chatter around the matter agree that these things are unpredictable.

@54 Renato: Yes, agree it will happen at some point and that they are very unpredictable; no one actually knows
I find it quite alarming how quickly all these self proclaimed experts suddenly appear and predict unpredictable events.
Not sure why I even asked other than sheer curiosity.

@stigger [53]/[54]

"...chatter that...will hit by Tuesday, ...just chatter?"

Mostly chatter with a significant chance of actually coming true... much like predicting that a tree is going to fall by wenesday. No particular tree, just a tree, somewhere, will fall. California just happens to have more seismic event's than you can shake a stick at, and with the hype and fear from the Mex 7.2, a lot of people have concerns over it.

I have my own pet loon theory about stress waves. I had a good track on one moving up the center of the Gulf of California, tracked it quite well from the quakes and swarms that would happen about every two months 135 miles north of the previous quake. It was a nice wave. Then I lost it in the clutter of SoCal and it's multi-fractured crust blocks. I can't say one way or another if any of the events going on there are part of the wave or not. I believe that there is increased stress there, but I can't prove it. California has quakes all the time. The Mendocino triple junction has them more often. ('cuz it's a triple junction)

Here's a redo of an old plot of mine

http://i30.tinypic.com/1zmzeo4.png

This is a plot of quakes along the length of the interface of the Pacific plate and North American plate from the Mendocino triple junction to the triple junction at the Rivera microplate (next to the Cocos plate) The vertical axis is the Latitude.

What you are essentially looking at, is the grinding along this fault system. Some creaks and pops migrate north, some migrate south. The disparity between North of â32Â°N and South of â32Â°N is because of the difference in Mexican seismic networks and US Seismic networks.

Other than that, it's a pretty neat graph.

Will there be a large quake in California? Most definitely. When? BTFOOM.

@Lurking @stigger: Talking about disparities, take a look at ongoing discussion over Philippines EQs on the other thread. It's really amazing what's happening at the Pacific right now.

excellent book you admit

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I was wondering if you ever considered changing the layout of your blog? Its very well written; I love what youve got to say. But maybe you could a little more in the way of content so people could connect with it better. Youve got an awful lot of text for only having one or two images. Maybe you could space it out better?

So I tried subscribing to your RSS Feed, and it outputted a "Malformed XML" error... Can you tell me if it's me or your site?

Friday Flotsam: All quiet in North Korea, what to watch for at Katla and the Kilauea lava lake

eklemetti — Fri, 09 Jul 2010 10:27:36 +0000

Friday Flotsam: All quiet in North Korea, what to watch for at Katla and the Kilauea lava lake

Quick hits to wrap up the week:

Looking into a skylight at Kilauea. Image taken July 8, 2010, courtesy of HVO/USGS.

Following up some news about Changbaishan/Changbai caldera in North Korea, Yang Qingfu, director of earthquake and volcano analysis and forecast center with the seismology bureau of northeast China's Jilin Province, says that the volcano appears to be quiet and that there are no signs of an impending eruption - at least not in the next dozen years. The bigger news (in my mind) is that China will be installing full monitoring (gravity, deformation, electromagnetics, fluid monitor and seismic) to watch the caldera that last erupted in 1903.
I've been getting a number of emails and tweets about seismicity around our friend Katla over the last 24 hours. Again, I am no expert on seismicity at Katla, but most of of the current earthquakes are very shallow (1 km or less), small (most < M1) and really, only 14 in the past day. If you're looking for a signal of a reawakening Katla, we should expect increasing magnitudes, earthquakes starting at depth (10s of km) and working their way upwards, tens if not hundreds of earthquakes a day and volcanic tremors, all of which are missing right now. However, never hurts to keep an eye on EyjafjallajÃ¶kull bigger sibling.
In the "File Under Lets-Worry-About-It-Now" folder, many people are suddenly jumping at the chance to buy volcano-specific travel insurance after the massive flight disruptions caused by EyjafjallajÃ¶kull. Now, I am not one to criticize proper planning, but I also find it interesting that a threat that was always there suddenly seems like a "new" thing. I mean, most people don't buy travel insurance for flights during hurricane season ... but maybe I am wrong. However, the insurance companies must be happy (for now).
There are also especially nice views of the lava lake in the Haleuma`uma`u Crater at Kilauea from the HVO webcam. Apparently the lava lake has been surprisingly steady over the summer so far - but we'll see how long that lasts.

eklemetti Fri, 07/09/2010 - 06:27

The cluster of earthquakes in the western part of Katla caldera is quite interesting. But it is too early to know if it means anything, as earthquakes are quite common in this area.

I was just about ready to ask Lurking to do a nice plot of the MÃ½rdalsjÃ¶kull (mind you, not the kettle) quakes.

That kettle does have a history of boiling when least expected and on short notice, but like you said, Erik, it's not a real swarm, yet. I'm sure to follow how they develop, but as JÃ³n said, EQs are common in that area - I've been waiting for a 48h lull that hasn't happened this far.

Am wondering about the linkage between Katla and EyjafjallajÃ¶kull, specifically:

- The heterogeneously episodic behavior of EyjafjallajÃ¶kull (including FimmvÃ¶rduhÃ¡ls)

- The correlated and coordinated pattern of alternated changes in ground displacement as measured by GPS across Iceland

- The correlation and coordination in tremor behavior across regions

- The nonlinear spreading and redistribution across the several parallel rifts.

It suggests to me that things are changing, that agent of change is at a wider scale than magmatic intrusion and/or plumes, that this flux of change causes the heterogeneously episodic behavior of EyjafjallajÃ¶kull's eruptions and it's coordinated linkage to eruption of Katla, that the agent of change correlates and coordinates the wide scale changes across Iceland

Copied to the current topic

I would like to hear from any one that was on Iwo Jima.
S/Sgt. GW Rosson

Posted by: S/Sgt. GW Rosson | July 9, 2010 1:52 PM
http://scienceblogs.com/eruptions/2010/02/submarine_eruption_near_japan…

you can just see the plume on the porol cam looks bigger than earlier

i thought, that during the summer months the icecap on top moves slightly it causes slight minor quakes as the sun heats and katla norm erupts in autumn according to past history

@leon -

The letter in the beginning of ÃÃ³rÃ³lfsfelli is NOT a 'P'. It's a letter that got dropped out of the English alphabet a while ago, and it's called 'thorn'. If you want to transliterate it - that is, use an English alphabet equivivalent - that would be 'Th', which is a close pronunciation of 'Ã'. In old English, the letter looked a bit different - that is why you see signs like 'Ye Olde Shoppe'; those are poor imitations of the original thorn; the 'Ye' IS 'The' in modern language, and is pronounced likewise. Here's more on that http://en.wikipedia.org/wiki/Thorn_%28letter%29

@Raving, Hi - do you have a copy of G.R. Foulgar's 'Iceland and the North Atlantic igneous Province' (MantlePlumes.org) Material, maybe, to be gleaned there for answers to part of you question, as it takes on the plume theory.

Im thinking I remember earlier caveats about material at mantleplumes, so bear that in mind....

@Kultsi, Askola, FI [2]

Still mulling that one over. (kettle?)

Meanwhile, after determining that MÃ½rdalsjÃ¶kull is the glacier that I keep seeing in the vedur.is data, it dawned on me what it was I was supposed to be plotting. (it's been a long week, sorry)

Plan View, last 5 days:

http://i28.tinypic.com/25rnu3q.png

For all, FL will likely be running a special on pre-greased mullet and redfish this year. Get it before it's flammable!

@7 your such a dick you know that. does it matter

@leon [11]

Actually, I doubt very seriously that he is an extremity of that description.

The "Ã" = "th" vice "P" has been covered ad nauseum ever since the recent Iceland eruptions have been going on. It not that you are wrong, you are just knowledgeable about that part of the language. I didn't fall into it since I usually just steal the spelling with cut-n-paste. One victim of the "Ã" issue actually found an obscure Icelandic site that used it with the incorrect transliteration, so it's not that big of a deal once you are aware of the correct way of rendering it. Now, if you want transliteration nightmares... try Cyrillic. When I did reports years ago, I had to keep a cheat sheet handy just to render the names in something that would fit an English keyboard.

So no, he's not that extremity... just possibly exasperated.

Lurking: I found it useful to overlay your plots onto the appropriate IMO EQ map.

>For all, FL will likely be running a special on pre-greased mullet and redfish this year. Get it before it's flammable!

That would have been a likely remark made by your sockpuppet character, 'Raving'.

:-)

Heh... Sockpuppet. No, not my sockpuppet, but I can't state that he is not someone else's sockpuppet.

Besides, better a sockpuppet than a happysock.

@13: I took your Grimsvotn plot from the other day and overlayed it onto the topo maps (IMO), which was useful, as it confirmed the EQ swarm alignment with the major fissure systems within the Vatnajakoll icecap area.

Similarly, the N-E trending EQs north of MÃ½rdalsjÃ¶kull seems to indicate alignment with major fissures north of Katla.

Kultsi posted a useful http addy for IMO EQ maps by week/year. That was welcome, because many of us wondered at the historical patterns of miniquakes in the area.

Homo fecae, hetero deus. Would appear to indicate commonality of seasonal-warming trend patterns, as many of us suspected and Erik suggested, in his blog post header.

Well, if you want one skewed for a specific overlay, point me at it and I may be able to tweek the x/y scaling so you get a better fit.

ok i take it back i apologize to Kultsi but i did think he was picking hairs for moment 'p' but i am from England with English local accent

@leon [17]

No biggie, I come from a part of the US where a seven course meal is defined as a 'possum and a six pack. When I originally came to Eruptions, it was because of the fissure event. I had no idea that I would learn about the Icelandic time capsule of the alphabet. English, the language, is a highly modified and adapted germanic derivative. A lot of our more fancy words came from France (Normans) while the more basic ones are closer to the original roots. (and the Normans were originally transplanted vikings who became latinized in their language) What makes English so prevalent is it's adaptability... which can also be bad when it gets down to specific meanings that tend to change with time. An example is that "bundle of sticks" word which now has an exceptionally abrasive meaning here in the US as opposed to actually being a "bundle of sticks."

Thanks for the offer, but I can snap the x-y coordinate systems to match with a bit of effort. I appreciate the plots.

You do know that I wasn't criticizing you, when I made the somewhat sarcastic comment on longterm plots of EQ versus Rio activity last week, correct? I've been plotting data for about 30 years. I know what a moving average window is, and how it works - and doesn't work so well.

When you are using a large moving average window over a period of months, with a dense data set, you build in 'lag' as a consequence of trailing numbers being weighted more heavily than leading numbers with each window progression, yielding an uneven averaging effect toward the end of the averaging period.

I tried dropping hints twice, my bad. I should have given you links. It's a common issue with moving average trend analysis, and there are interesting alternative methods, derived from economic analysis. The StatSys program package website has a good discussion of these statistical methods. It's a handy website to bookmark as a statistical reference guide.

Good-oh, Leon, for apologizing.
Isn't Kultsi a 'she'?

>An example is that "bundle of sticks" word which now has an exceptionally abrasive meaning here in the US as opposed to actually being a "bundle of sticks."

??? I know it's been a long day(week) here, but that blew right by me.

For your entertainment, some Icelandic pics. There's even a volcano in some of them!

http://www.facebook.com/album.php?aid=2064028&id=1528659644&l=1787628b94

Let me know if the link works.

Thanks!

Passerby: Can I echo your ??? ? Can't think of anything at the moment (well it IS 0611 here) except maybe Fascism, whose original symbol was, indeed, a 'bundle of sticks' (with an axe)

@ Fireman - Wow! link works - thanks for posting. Got any more?
@ Passerby and Mike Don...... wakey, wakey! Let us know when the penny drops :-)
Hint: many years ago when our school choir toured the US, the choristers were told not to use the UK slang for a cigarette........

@Passerby

Ref: the "bundle of sticks" thing. I shouldn't have used that analogy. As you and others have clearly demonstrated, it was a poor choice. Kathryn, Australia is on the right track, and the Fasces as a bundle of rods with an axe is probably derived from the same root word... but this bundle was usually meant for sticks you would gather up to toss into a fire rather than a symbol of power or authority. Oddly the US dime had the Fasces on the obverse until 1946 when it they made it into a torch. Must have been due to that fascism relationship.

So... in the meantime, just mark this as an obscure reference that should be dropped.

Hey, look! A graph!

http://i26.tinypic.com/dos1h2.png

Pac NW, View North 2010 quakes from the earthquake.usgs.gov/earthquakes/recenteqsus/Maps/US10/42.52.-130.-120.php listing.

Actually, that graph is backwards and mislabeled. The view is actually South.

Here's the North looking view.

http://i27.tinypic.com/vep2x2.png

I really wish the little lava pond in Halemaumau would emerge from its hole and spread around the crater to return to its former pre-1924 glory. The way Mark Twain saw it, when it was a wonder of the world.

@Passerby [19] -
Swinging there the last time I checked...

@Kathryn [23] -
That word would have been very badly received indeed, as badly as a reference to someone's merry lifestyle.

Well, it wasn't intended as such. I did a two hour stint hunched over a laptop motherboard and 5 hours of road time. It was about the only changing word definition that came to mind. I've always been amused at that one since the meanings are so far apart. It's almost unfathomable how the definitions can be connected.

A better definition morph world be "gaff" or "gaffer"

A gaff hook is used to retrieve a line, impale something with a hook, or to make a verbal mistake. A gaffer has multiple meanings, including an electrician on a movie set or someone who hand forms glass.

The gaff hook is a nautical variation on a pike pole, which was used by pikemen... and a pike is also road... or a type fish.

@Kultsi:
Oh my, swinging in the britches:)

@Diane in the former thread:
Thanks for the explanation of Eriks rootless barbarians!

@At all:
Gotta love the swarm at HerÃ°ubreiÃ°artÃ¶gl, I have wet dreams about hearing american news-anchors trying to pronounce that if HerÃ°ubreiÃ° erupts. Strange place really for a swarm, I would have expected that in Askja and not in HerÃ°ubreiÃ°.
Perhaps Lurking could do a plot for HerÃ°ubreiÃ°artÃ¶gl and Askha area, if I am not imagining things there have been quakes on and off there for a couple of weeks.

@Passerby and Lurking:
I am starting to be jelous, I want to know who is my Sockpuppet, or do I have a sock in my puppy, or...? Questions questions:)

And here is something for those of you who are not familiar with the HerÃ°ubreiÃ° and HerÃ°ubreiÃ°artÃ¶gl volcanic system in relation to Askja and KverkfjÃ¶ll.

http://notendur.hi.is/heidi/Stuff/herdu06report.pdf

Lurking... "The gaff hook is a nautical variation on a pike pole, which was used by pikemen..."

And is still used every day by firefighters:

http://www.gomed-tech.com/catalog/nupla-pike-pole-with-d-grip.htm

I didn't understand the "sticks" ref either, but I went to my trusty urban slang dictionary:

http://www.urbandictionary.com/

My fave is the b-word in the Queen's English. Back in the 70s I was on a train, discussing the differences in language between Murikan and True English, and when we got to the B-word, the couple, parents, asked us to not use the word. It also ended the conversation. Heh.

@Carl, nice article. It also highlights a common human trait, something we can all share.

"As the weather was turning cold during the pick-up trip and it had to be done relatively quickly, no downloading was done in the field, but was done at the first opportunity in the lab of the Science Institute in ReykjavÃk."

Nothing like scampering around in rough terrain trying to get your stuff when the weather is getting bad and your freezing your arse off.

There's an interesting article in Science Daily about the nature of 'sticking and slipping" in the two Indonesian earthquakes (2004, 2005) and what affects the the length of the slip in subduction faults. Excellent theory with great predictions.

http://www.sciencedaily.com/releases/2010/07/100708141535.htm

@parclair [32] -
You lost me here - there are close to one hunnert thousand b-words in the Urban Dictionary, and I cannot for the life of me think of a very bad one. The one for a female dog is about the most common, but I don't know any differences in meaning on different sides of the Pond for that.

@ kultsi, The word is a swear word in British English and begins blo***. I always get trapped in these conversations, I don't know why. Once, during a viewing of Goldfinger, I tried to explain the why the character Pussy Galore was so funny. Heh. No more questions, please. ;-?

@ Kultsi... I wonder if the b-word could be 'bugger'? Which, to someone who has now spent a lot of time in the USA, is a peculiar usage. The literal meaning (archaic and seldom used) is 'to engage in anal sex', but it's a very common everyday expression in British english:

'it's raining - well that's buggered our plans to paint the house'.

'well I'm buggered!' - as an expression of surprise.

'that little bugger next door broke our window with his football!'

'I dropped a brick on my foot; it hurts like buggery'.

Very common expressions and very English; would sound very peculiar in American English , replacing 'buggered' with 'sodomized' - which would be the literal equivalent!

Bloody? That word has slipped down the scale of seriousness in swear words in the last half century or so; it would be considered pretty mild these days, although perhaps slightly... lower-class? and maybe offensive to the ears of those with pretensions! It's very freely used, on TV too.

The words considered truly offensive in relatively polite circles in the UK are the same as in the USA these days, especially the 'f' and 'c' words. Although 'f' might be freely used between friends, it shouldn't be with strangers.

Hi everyone,
Well, I see that the weather is back to normal at Eyja.Anybody who can see a plume must be using a Crystal Ball.
Talking of crystal balls,it's got a bit "biological" on here recently ?? Have to lift the tone above the waist line Folks..
@#29 Hi Carl,
I have been keeping an eye on HerÃ°ubreiÃ° since mid April this year.It's not the first time that there has been a small swarm there.Who knows but it's been a damn long time since "she" erupted.

@those trying to help me w. swearing properly -
I once had a conversation with a Briton on the merits of pronouncing the name of a German philosopher correctly; his given name was Immanuel. The proper pronunciation is something I won't use outside the reference to said philosopher.

Otherwise, we Finns find the swearing among the English speakers lacking in force and being tame. Maybe that's because we don't get it - which is not a bad thing; much less bruising.

Fireman, my thought of your last example of buggin' things was, "Hmmm... Is that from personal experience? Must be bad if it hurts as much as dropping a brick on your foot." Well, that was just a train of thought on the side rail; I get the idea about the usage.

Carl's article citation was a mere technical warm-up to a much better article:

Lower-crustal earthquakes caused by magma movement beneath Askja volcano on the north Iceland. (2009).
www.springerlink.com/content/wk7h583281766611/

and, not surprisingly, since the g-god Einarsson had his hand in the pot, it leads to a truly masterful article:

The fissure swarm of the Askja volcanic system along the divergent plate boundary of N Iceland. (also 2009)
www.springerlink.com/content/q3p23lj648k8x277/

It provides an explanation for much of the seismicity observed, in the Triple Junction (North American, Eurasian plates and Hreppar microplate).

Most of you can't access these papers, so you can't get from 'there to here' conceptually. Instead, we'll turn to the MS thesis of the lead author, a co-production of Einarsson and geological wizard, Harald Sigurdsson, that thankfully open-access.

You get all the tender goodness of that last paper, with the full bells and whistles seismic background and process explanations, plus a full reference base.

The fissure swarm of the Askja central volcano. AR HjartardÃ³ttir (2008), 125 pp.
www.raunvis.hi.is/~astahj/MSritgerd_ARH.pdf

Now ain't that just ducky?? We have here, the ne plus ultra of explanations for the EQ patterns we see above Vatnajakoll, near Askja and KverkfjÃ¶ll.

Thanks Harald and Pall! You guys rock!

@Passerby -
Don't we tip the hat at Ãsta Rut? It's her paper, after all.

Yes of course! But this is a master's thesis, with all of the underpinnings and content style that are typical of Pall and Harald's technical thoroughness and vast knowledge base. The late GuÃ°mundur E. Sigvaldason, professor emeritus and former director of the Volcanic Institute, also supervised this student.

Kultsi 36: In respect of the differences between American and British usage, can I cite the Austin Powers film, "The Spy Who Shagged Me"? Title had 'em rolling in the aisles in UK, but clearly didn't have exactly the same meaning in the US, or the corporate suits at the film company would have had conniptions :o)

The paper we want to read is the third paper by ARH (cited above), but the thesis lays much of the explanatory groundwork needed to understand the shallow tectonic (fissure intrusions) and deep magmetic processes.

Unfortunately, hardcore chemistry, non-medical biology and especially geology along with engineering technical journals have few electronic open-access papers posted.

Do read Parclair's link at ScienceDaily. The paper is:

Contrasting DÃ©collement and Prism Properties over the Sumatra 2004â2005 Earthquake Rupture Boundary. Dean et al. July 9 2010. 329:207-10. DOI: 10.1126/science.1189373

www.sciencemag.org/cgi/content/abstract/329/5988/207

The article graphics and supplementary mat'l are open access.

@mike don [44] -
I'm in a position to get it from both directions; the vast majority is from the US, but that does not mean that I don't get the UK idiom, too, like the title of that film - at least occasionally.

@Diane, N CA (in former thread): This is Rialto, from Rio. Please you donât have to apologize: I change names all the time here. I tried to keep it as a nickname, but our fellow bloggers rejected the idea.
BTW Iâve been watching the film âDevil at 4 oâ clockâ on TV (Spencer Tracy and Frank Sinatra) and I remembered you saying you liked such films when you have a cold. I had seen it when I was a kid, but it proved to be better than I thought. If you havenât seen it, keep it as a hint to the next time you catch a cold (God forbid). Iâll leave the comments for later, donât want to spoil the experience.
@everyone: If that isn't a steam plume on Eyjaf's slope, what is it then?
http://www.simnet.is/jonfr500/earthquake/vefmyndeyjafjalmulaen.html

Just done snarfing all these articles - odd but nice that Iceland Telecom subscribes to Springer's for all of its users.

You're not the only ones keeping an eye on the area north of VatnajÃ¶kull. Mum says that the last time she was in the area (quite a few years back), she could feel the tension in the ground. Got me wondering if electric or other fields vary a lot in EQ zones.

@Reynir, NK
Your mother's words reminded me of the film I mentioned above, when Spencer Tracy's character (a priest) says: "I can feel the devil under my feet."
Magma is kind of "devilish" indeed.

@Renato - I call them clouds; they are steam, too, but not of volcanic origin.

@Reynir - subconscious reading of the terrain & sensitivity to micro tremors, I'd say. Some are good at witching wells; my attempt at that resulted in us getting a really good well where others said 'no way!' I just looked at the lay of the land and told the back hoe guy: dig here - and at one meter he hit the bedrock; 15 meters of borehole brought water and 25 meters made a good well. Ten meters from the well we had gone four meters deeper with no sign of bedrock; that's where we built our house.

Reynir: read
Iceland Consortia for Electronic Access.
www.hvar.is/sida.php?id=154

I hereby formally request honorary appointment as scientist- citizen of Iceland.

@#52 Hi Reynir,
I too formally request honorary Icelandic Citizenship and Acting Role as Scientist (Makes for a much broader scope of which type).

@#48 Hi Renato,
Umm,i've been watching the cams on and off for a few hours now and it's very hard to tell.If I was forced into a corner I would have to say "Yes,there is still activity at Eyja".

And two small swarms,Grimsey and HerÃ°ubreiÃ°.The four at HerÃ°ubreiÃ° were on top of each other in the space of fifty minutes.

@Kultsi @Adrian #51-#54 Hi there! I'm stuck to this computer for days trying to finish a paper due to next Tuesday, but every now and then I switch to Eruptions blog and, of course to Eyjaf's webcams. I'm addressing to you guys who were "present" to Friday's activity and I believe, and maybe I'm totally wrong, that the event was a bit underestimated.
I buy Kultsi's theory of cracks opening under the lake, and I think that it's still happening, sporadically though, even if the weather is not helping observation. At the moment I posted my comment on a "steam plume on the left slope" the weather was fair enough to tell steam weather clouds from volcanic activity, i.e. steaming from the cracks. Now it's gone. But at that instant you could really see a puff. And I think there are still more to come, weather permitting.
On Friday I saw snowflake-like particles hitting the lens of HvolsvÃ¶llur cam, which couldn't be snow and I explained them as being light ash, emitted or carried by the plume, which was, then, turning from white to gray. But as I said, I can be wrong. And yes, I saw a blast too. As for the "lightning, I admit it could have been a flickering of the image, but there was a clear moment when the crater rim burst into steam (on Friday). Anyway I'm grateful to have shared that special moment with you guys and others that are to come.

@#56 Hi Renato,
Yesterday was a good day,the best for some time.I think that we all agree that Eyja has not finished yet,whatever it be.
The shot from Mulakot at present is not "convection cloud".It's steam being blown over the ridge,then upward.

I think I'd enjoy hvar.is even more, were it not for how much I have forgotten since school. I really feel like an old fart at times.

Evenin' all!

She's still steaming albeit not as much as a couple of days ago (Thorolfsfelli cam). To my lay mind, that must mean magma is still (moving) close to the surface. The reason there is no eruption at present is because a) there is no magma pushing up from deep below, and b) all available old magma sitting in the piping that could be revitalised, has been revitalised. Here endeth today's lesson in how to state the glaringly obvious.

PS. The eq activity of the past week or so E-ENE of Lady E seems to be centered on the Godabunga area where there is a substantial body of magma sitting since 1999(?) about 1Â½ km down. So where do you place your eBeer? Nothing more, renewed eruption at the main crater or an eruption at Godabunga?

Lady-E is DONE. Maybe she will roll over in bed but she sleeps the long sleep. Katla = Baaa humbug no big deal.
Look at the rest of the world for action.
Where will the next VEI 3+ come from is the question. Lady - e I doubt it....

@Dasnowskier: They said the same back in the 1820s, too. Ya gorra wait for at least three and preferrably six months before stating that an eruption is over.

@#61 Reynir,
Well said that Icelander !

EyjafjÃ¶ll is known for its on/of Eruptions, she usually rests in between her eruptions,I dont trust its over yet..
They said it was over in 1820s also, but she took them by surprice.
there is still Hot Molten rock in Fimvorurhals, and same is belived under EyjafjÃ¶ll, so even tough it seems calm, it just might be brewing deep down there still..
A sleeping/dormant Volcano is always a possible bomb,even after 1000 years...
and EyjafjÃ¶ll well its only a few weeks since her last eruption and we should not state or even belive that its over.
Btw remember that Katla usually have an eruption between 6 months and a year after eyjafjatlajÃ¶kutl. so dont push that eruption aside either, it just might go boom with out giving any real signs....

Hi, to me now looking on the Mila web cams lady E reminds me how she looked in may. steam increase then eruption follows

I still think she's done for this eruption. Maybe a VEI 1 burst ...IE rolling over in bed but, I think all significant eruptive activity is done.
Past Katla eruptions near Eyjaf were coincidence. At this time I have seen nothing to make me think Katla might go. If Katla starts to rumble before say, 1 year after the start of this eruption then I will change my tune. But now that we have monitoring devices... if the quakes do not come from the direction of Eyjaf then I will still not be convinced of a relationship. Katla erupts much more often than Eyjaf.

@65 katla followed after the last three eruption at Eyjaf and was explosive on each time i also think there is link deep underneath that we cant see i might be wrong on link part and katla is know to erupt within months of lady E

@#64 Hi Leon,
It's not a bad view on Thoro cam at the 'mo but try Mulakot:great view as the plume is in profile.

I only see clouds on Mila.

Mulakot is mostly weather related as well. Topography is the major cause of those clouds

@Dasnowskier

"... Katla = Baaa humbug no big deal.
Look at the rest of the world for action."

Yup... all done, not a threat, nothing to see here.

Keep thinking that. By now it is VIRTUALLY IMPOSSIBLE that anything could ever happen over at Katla.

Oh, BTW, you happen to take a gander at the quakes that have occurred in July?

http://i29.tinypic.com/zsvorm.png

Funny... doesn't look like a peaceful sleep. It's not a sign of a pending eruption, but it clearly indicates that there is no rest for the wicked.

@67 cheers Adrian having the same feeling as i did back in may with steam plume then eruption but i could be wrong keep thinking she could split open to the side and all that water in the crater gushing out on 'p' cam not like i want that to happen of course watching the cam to much i think

@68 look closer

@Lurking
"By now it is VIRTUALLY IMPOSSIBLE that anything could ever happen over at Katla." These are not my words. Improbable is closer to my thinking. I never say or think impossible with a volcano (Chaiten).
Virtually impossible and I would build a house on the summit, if it was sold ground LOL.
I do however see the interest is Scientifically proving the relationship between Eyjaf causing Katla to blow. That would be neat, however I do not think it is so.
I hope I am wrong ..or actually I hope I am right. Who needs the massive economic disruption Katla might cause to Europe.
GO Netherlands

Well... Eyj was beginning to become a geo-tourism thing. So that helped... a bit. It's farm more interesting to gaze at an erupting volcano rather than stare at a tarball or a flailing pelican...

@65 you say katla erupts more than lady E true but katla does not cause lady E to erupt. lady E cause Katla to erupt, a trigger or connection and one thing in life that i learned was never say never

...from the newer thread...A few mid-June pics I hadn't seen before of glacier & crater lake at http://www.earthice.hi.is/Apps/WebObjects/HI.woa/wa/dp?pictureID=101645…

last eruption at lady E before 2010 happen back in on the 19th December 1821 to January 1st 1823 Katla erupted on june 26th 1823 to July 23rd 1823 almost seven months later, going back to 1612 lady E erupts no given days date with Katla erupting on October 23rd 1612 and again going back to 920AD lady E erupts and Katla again follows in 920AD All happens in the same year as lady E sleeps katla wakes up
http://www.volcano.is.edu/world/volcano.cfm?vnum=1702-02=

@ 21 Fireman -I'm slow to catch up - Nice Photos!! You did get there - I wasn't sure - how was it to be there? Thanks for posting the link.

After seeing the hardship of the ultrafine ash and gases to area farmers in May and early June, and more recently 'ash storms' kicked up by convection and storms that are redepositing this erosive material, it is perhaps best to be prosaic in the Mediterranean way.

We have seen many marvelous sights during Eyjaf's eruption this Spring - first at the picturesque Fimvorurhals lava fountains and then later at the crater, in a powerful and at times, achingly beautiful, lightning-colored night-sky column display of Sturm und Drang.

Iceland has been most gracious in allowing so many from so far away, to play voyeur. We are pleased and grateful with all that we have learned here, much of it provided by IES and IMO. Thank-you!

@leon

I don't think that is an accurate assessment. It's that correlation not equaling causation thing. Katla erupts on average, about 64.5 years, with an SD of 48.3 years. In a nutshell, that means that about 64% of the time, Katla will erupt within 16 to 112 years since it's previous eruption.

For EyjafjallajÃ¶kull, the average is 423.6 years and a range of 177 to 669 years. (245.9 yr SD) It is almost impossible for Eyj to go off and not have a Katla eruption pop up within just a few years. Why? Simple, No matter when Eyj goes off, 2/3rds of the time Katla is either going into or is already at an eruptive phase.

Could it be possible? Definitely. Is it proved? No.

In 540, Eyj Erupted. Katla had already erupted about 10 years prior. In 590 Katla went off again.

In 920, Eyj Erupted. Katla had already erupted in 904, but went off at the same time (920)

In 1612, Eyj Erupted. Katla had last erupted in 1580, 32 years earlier. So, it erupted in 1612, and in 1636, and 1693, and 1721.

In 1821, Eyj Erupted. Katla went off two years later in 1823, and again in 1860, 1918 ...

Katla tends to erupt on it's own schedule no matter what Eyj does. Can there be a connection? Well, that's why they are always trying to figure the piping out underneath the two.

Let's put it a different way. While "Lady" E may take a while to get around to doing her thing, all Katla needs is a beer and your good to go.

Hey there! She's back again. Look at the plume?
Ok, just coughing a bit. But she's beautiful doing so! And I agree with @passerby: thanks for Iceland and Icelanders, Mila, IMO and all!

@leon @lurking I tend to agree with that - Katla is a "more often" volcano, whereas EyjafjjÃ¶l keeps her secrets to the very special generations... :)
But then why, at the very beginning, most volcanologists put a Katla's eruption into question? And why are we still speculating on this? And Lurking, I'm sorry, but you are the first one to tease us with your graphs, who keeps our fantasies going. (to whom I am most grateful!) :)

@Kultsi, where are you? I'll keep an image from ÃÃ³rÃ³lfsfell cam for you. Is that some sort of "Icelandic cloud formation"? LOL

It's 4:30am, Sunday morning in Finland. Kultsi is in bed.
Shhhhh.

Go back to your paper.

@passerby! I've been working on it since 9 in the morning, so, its time for hallucinations...
Here we go: Lady E is behaving pretty much like she did on Friday morning. Only the weather is not collaborating. But my theory is: there's a crack, lava is still hot in the crack, lake spills and she goes puff, carries ashes mixed in steam droplets, plume cools down, and splashes back to the rim. Like a counterfeit of a plinian ash-column break.
Uh?
Ok, Rialto, back to your paper.

All I see on any of the cams is clouds. Maybe enhanced by the hot crater lake but just clouds.

@Renato -
I'm here, now. Just to be on the same page, you are prolly talking about the cloud about a kilometer up GigjÃ¶kull from the split rock. That is not one of the clouds that appear from thin air, that's steam from the end of the lava travel, or close to it. Easy to spot, as the source is stationary and even puffs from time to time. It does that whenever there is enough water for it to steam.

As to the source of the water, I cannot tell. It could be from the crater lake, but most of that seems to get boiled away close to the crater, on the upper part of GigjÃ¶kull. It could very well be from the lava canyon walls, which are ice mostly and it's summer.

@Renato -
If you put the crack into the lake, you don't need the collapsing column: water flows into the crack, heats up for a while and boils out in a gush of steam, taking water on top with it to splash over the rim. Geysir action, IOW.

A nice steam plume visible on both MÃºlakot and HvolsvÃ¶llur cams.

#90 @Kultsi, I hope I didn't bring you out from Queen Mabe's brest! Yes, it keeps splashing over and over. Not a South American- Carmen Miranda-Chaiten way; no. She's polite, Nordic Garbo style. Even when she burps she's chic. That's what fascinates me about this volcano.

@Passerby (#20) Ever eaten prairie oysters?

Homo fecae, hetero deus.

An example is that "bundle of sticks" word which now has an exceptionally abrasive meaning here in the US as opposed to actually being a "bundle of sticks."

??? I know it's been a long day(week) here, but that blew right by me.

Posted by: Passerby | July 10, 2010 12:31 AM

http://tinyurl.com/35husre

@Passerby Yam! Thankfully it was not "maggots". They don't go well with oysters... >;)

Just picked that from Wikipedia:
"In June 2010, Volcano expert Hazel Rymer said seismic activity was increasing as Askja and that an eruption could be around the corner. It was ruled out that any activity from EyjafjallajÃ¶kull was responsible for the increase in activity at Askja. The news came as scientists continue to watch Katla."
Judging from ongoing activity looks like it's pretty much around the corner...

A maggot played upon fagotti can be rather pleasant. :)

http://tinyurl.com/2vpndzc

I've printed out a copy of Foulgar's paper and will read it presently. Maybe it will register better on paper. Thanks for the suggestion.

And now for the shipping forecast ...

|-I

Definitely rather more pleasant than oyster maggot broth.

Gorgeous effect of sunlight on the plume. frÃ¡ HvÃ³lsvÃ©lli.

I think the sun is rising right behind the steam plume. Amazing!
Bring the fagotti and lets hear a piece from Purcell.

Askja... perspective view looking North West. July Quakes

http://i29.tinypic.com/19knr7.png

When will we, if ever, have another eruption as spectacular, magnificent and covering most of of the spectrum of volcanic expression?

First, the intense earthquake activity (feb-march) beginning not long after Erik had put up a topic "Rocking on the Reykjanes Ridge", which kept us all in suspense - "will she, won't she" - and speculation as to when, where, how.

Then, after what seemed an eternity to an expectant community, the marvellous live broadcasts of the FimmvÃ¶rduhalsi Hawaiian to PelÃ©an fountains, lava flows and phreatic explosions.

Finally, the main show - Surtseyan, Strombolian, Vulcanian to almost sub-Plinian with jÃ¶kulhlaups, ashfall, closed airspace and what looked very much like pyroclastic flows as well (April 17th).

The 2010 eruption of the volcano underneath EyjafjallajÃ¶kull - Icelanders, could we please have a proper name, she thoroughly deserves one this most beautiful of all your volcanoes - can also be claimed to be the first (ad hoc) on-line workshop in volcanology that taught hundreds, if not thousands, of ignoramii such as myself the rudiments of volcanology and knit a community truly global in scope. Both Dr Klemetti and Dr Behncke have summed it up as a "once in a lifetime eruption". Now that it is seemingly over, deep down I think we all hope for a twist in the tale because we do not wish it to be so.

Heh. They are having picnic on the GigjÃ¶kull end moraine: four cars already, and one seems to be a bus.

@#102 Hi Henrik,
May I say,Bravo,for such a eloquently written and succint post. Your last three lines have put into words what should have been said around the third week of May when the main eruption died down.I sincerely believe that there will be "a twist in the tail".
Re your post #59,I read it last night with a slowly expanding grin on my face. Your theory of the "revitalising magma" certainly holds water.And yes,it is "glaringly obvious,chuckles.
I won't take you up on the e-beer just yet as I am quite undecided at the moment.May'be if the main crater re-activates in a big way,then we could have a bottle of e-champange and share it with everyone.
P.S. Always thinking about the Icelandic farmers though.

Good morning everyone!
Before I go back to my paper I would like to join the toast to Henrik and his wonderful speech and to thank Lurking for his new graph.
Lurking, I was trying to figure out the other volcanoes around Askja and I think they should show on your map, do you think it's worth it? I mean HerÃ°ubreiÃ° (litle further NE) and KverkfjÃ¶ll (to the South, under VatnajÃ¶kull),as it seems to me they are pretty much involved on this event. Or?...

@102 @Henrik
And we must be thankful to the fact that, except for a couple of poor lost tourists,and perhaps some livestock, there were no casualties from Eyjaf's eruption. As for the farmers, I remember watching an interview made by a Brazilian journalist who went there where the ash fall was more intense, and the farmer said with a smile "- We Icelanders are used to our volcanoes. We love them!"

#106 As for the air traffic disruption, oh well, I think the world needed something like that to stop and reflect a bit.

@80 lurking i agree katla erupts at different times, but i was on about when lady E erupts katla tends to follow months later. what i was thinking was the eruption explosion from E causes energy to spread out and makes katla become more active and because the magma chamber for katla is deeper down and lot bigger so its a lot longer to erupt.but what i just written is just a theory!going back in April 2010 media was very quick speculate to say katla will follow.im just gone sit back keep checking the web cam and wait,and go with @83 Renato on this one. more links here if your intrested. http://geology.rockbandit.net/2010/04/...viabrian/
http://michaelix.livejournal.com/

HerÃ°ubreiÃ° - that's North of VatnajÃ¶kull and NE of Askja - keeps shaking. Nothing very powerfull, but persistent, at about 7 km in depth; about 50 EQs in the last 48 hours. Neither is that something new, 'cause swarms in that location have been seen before.

Like Carl, I'd like to hear a news anchor trying to pronounce HerÃ°ubreiÃ°artÃ¶gl - which is actually easier than EyjafjallajÃ¶kull.

@#109 Hi Kultsi,
HerÃ°ubreiÃ°..yes,i'm keeping an eye on that area.The swarms are sporadic but increase in intensity each time.They also seem to be on a Nne/Ssw line in general but they are very close to the North Atlantic Ridge so perhaps hardly suprising.

@Lurking, #101: check your Askja coordinates. Something doesn't look right with that plot.

Plus the fact that the IMO's helicorder for Askja has been down,and out,since,I think,the end of June.Makes me wonder how much damage it sustained as it went "off-line" after a particularly violent bout of activity !

@Passerby

Dunno, here is the Askja data from the plot and the source that I used.

65.0316.751.516 - Dplot
65.03Â°N16.75Â°W1516m - www.volcano.si.edu/world/volcano.cfm?vnum=1703-06=

Now there are a second set of coords also listed: 65Â°2'0"N - 16Â°45'0"W. I went with the first set.

It is a rather large set of nested calderas, and this is the listed summit... which is probably the just the highest peak in the area. I have the same issue with my Katla plots... the point that I label is just the one that shows up at that site... even though the actual caldera is sizable.

Here is a plan view of that same graph with the surface turned off. The outlined triangles are other volcano peaks/features/items appearing in the www.volcano.si.edu list.

http://i26.tinypic.com/nlwsgh.png

@leon:

That's sort of my point. It's almost impossible for Eyj to erupt and not have Katla erupt. That's what Katla does, and it does it with such frequency that the correlation has little meaning. It's similar to matador walking into ring and waving a red flag. The color of the flag really doesn't matter, the bull is going to charge anyway. Just like poking a hornets nest with an oak rather than maple stick. (just make sure you are ready to run)

Part of the problem is that a lot of media sources will trot out whatever show pony that will garnish them the most viewers... and viewers crave excitement, danger and sex. (at least according to the formula) Witness the Yellowstone coverage every time there is a significant swarm.

@Renato I Silveira

Actually, the other volcanoes were int that plot but they were obscured since I had a terrain layer turned on. You can see them as the outlined triangles in the following plots.. which use the same data. There may still be an issue with the actual location of Askja, but until I get a better source, I'm keeping the one I had. (as noted above)

NOTE: the depth of these plots is large.. upwards of 2 degrees. (thickness of the cross section)

View North:

http://i30.tinypic.com/15x21k.png

View East:

http://i29.tinypic.com/2vju8hf.png

Did you grab a copy of the MS thesis I posted yesterday on the Askja dike swarms? Pages 23 and 25 have the figures we want.

I would take your last plot and overlay it onto a window image grab (I use WinSnap).

I grabbed a thesis... there were several links and I wasn't sure which one was the targeted one. I have the one that points out that one of the authors is tromping around a pit crater with a red rucksack. He was labeled as predominantly as the interface of the shield lava and the hyaloclastite and I wouldn't have seen him with out the label. I don't think it's the one you are refering to since pg 23 and 24 are talking about the "Krafla Fires" (MSritgerd_ARH.pdf)

Google search, 'The Fissure Swarm of the Askja Central Volcano'.

When in doubt, I'd go with the IES topology for Askja, given the variation in reported coordinates.

Your plot lines up beautifully with the fissure map graphic with EQ 1998-2006, page 25.

Evidently, this is the correct document. I used the page numbering of Adobe rather than the one on the page.

A first try at wrangling the data onto a background image from Figure 12 page 25 looks... sort of promising, but likely contains some error. Note the tick mark in the lower left corner, that is 17Â°W and does not line up exactly with the plot's 17Â°W.

Do note that this is a "tight shot" which is zoomed in quite a bit.

This plot uses the same data set as the previous ones and has not been updated to "right now"

http://i29.tinypic.com/k12xbr.png

Anyway, I have to go pick up a bushel of corn. Be out later.

Scrap my plot. It's WAAAAAAY off on the vertical scale.

Just a minor aberration Lurking.
Eyja now has a good head of steam,now showing,on Thoro Cam.

Better version, still off by a couple of minutes... but much closer.

http://i25.tinypic.com/9fxwus.png

@Raving [97] - Ya forgot the most important part! www.youtube.com/watch?v=dFdas-kMF74

Avast me hearty.It's Ye Olde BBC Shipping Forecast Theme !

@#121 Lurking,Hi,
Pretty well confirms what I thought.Good old HerÃ°ubreiÃ° wins the prize.

She's showing a good head of steam this evening and I think is still affecting the weather across the UK. We still have 'chugging' lines of clouds like steam train puffs across the sky, though the map shows no concentrations of ash in the air. (I think the link showing ash concentrations is: 'conccol_VO_1_.mht') And we are enjoying a lovely heatwave.
I also wonder whether the potentially explosive link to Katla may be part of the water system which is still feeding Lady Eyaf? Where is the water feeding in from? Is it seawater or a deep freshwater source, or is it all from the glacier?

Finally a non-weather enhanced view of the steam plume.
Looks like 2 centers of activity. Vigorous as well
However I do not think it is strong enough at this time to effect weather more than a few miles away due to clouds.

Lady E is clearly huffing and puffing: the steaming is cyclic and the amount varies quite a bit. Geysir-like action, in the crater, IMO. There are two places of steaming, the crater and the lava canyon's uppermost part (2-4 km?). There is no melted rock in contact with the water, just bloody hot stone that boils the water.

@Lurking:
Hope the bushell was full!

Could you do us a favour and not only mark out Askja, I know it is a jolly and nice volcano, but the thing is that the majority of activity quakewise the last decade has been at H and H-tÃ¶gl. (That dear Passerby was why I didn't go with the other articles, they where concerning Askja mainly)
I know that it is counted as an unlikely one to erupt, but it is the currently more active after all.
Thanks in advance!

@Lurking part 2:
Or... (fawning shamelessly)
Could you do one just for H and H-tÃ¶gl? I am having trouble seeing if there is signs that the quakes might indicate rising magma.

#126 @Kultsi A giant geysir. Could only happen with Lady E.
@Lurking
Thanks for the graphs. I'm sorry to annoy you asking to show the names. But I didn't know we were talking about a forth volcano: There's Askja, and HerÃ°ubreiÃ°, and KverkfjÃ¶ll. HerÃ°ubreiÃ°tgÃ¶l is yet another one? I like the tuya shape on HerÃ°ubreiÃ°. But Wikipedia says it has erupted in Pleistocene, which means it could be dangerous or just that there is no chance of erupting?

@ 21 Fireman, your photos are stunning! The light, the rainbow, the colors! (And of course, the volcano, LOL) Thanks for sharing!
http://www.facebook.com/photo.php?pid=31278623&id=1528659644&l=1787628b…

HerÃ°ubreiÃ°artÃ¶gl, this is quite a nice site with a lot of information for those of us who like to visualise what we think and talk about:

travelingluck.com/Europe/Iceland/(IC32)/_2630507_Her%C3%B0ubrei%C3%B0art%C3%B6gl.html#local_map

HerÃ°ubreiÃ° & its immediate vicinity has had a lot of seismic activity over the past three or four months, but nothing near the present amount. Some 55 quakes over the past 48 hours represents quite an increase in activity, but will anything in the way of an eruption happen? Probably not, but then again... ;)

@123: The point of yesterday's post was to show that the IES-UK collaborative effort had hammered out an explanation for the discrete patterns of shallow and deeper earthquakes in this area:

'Close to Askja the swarm is dominated by eruptive fissures....This may indicate that magma pressure is generally higher in dikes close to Askja than farther away from it.'

On the left side of the graph, those volcanic EQs are dues to magmetic movment. They are the EQs close to the central volcano in Lurkings newest graph.

>The proportion of tectonic fractures gets larger with distance from Askja. ... Volcanic fissures and tectonic fractures are either oriented away from or concentric with the 3â4 identified calderas in Askja.'

Right side of graph, green-colored lines and in the vicinity of HerÃ°ubreiÃ° - those are lined up with the beach ball stress diagram shown in the article supplemental material (the article itself wasn't open-access, just abstract and supplement pdf file).

The fissure swarm of the Askja volcanic system along the divergent plate boundary of N Iceland (2009).

This green-colored basalt area around HerÃ°ubreiÃ° dates from the last major glacial rebound period (4500 years BP) of volcanic activity.

'Most of the tectonic fractures are located in the northern part of the map, both in hyaloclastite ridges and post-glacial lava flows' (from the MS thesis, page 69/125).

Generally, in this area, the shallow quakes are due to tectonic stress from plate spreading.

@124 the heatwave that affecting the Uk is down to heatwave in Europe trying to push west and down to southwest with gulf heat trying to push north east and less active Atlantic low fronts to the south of the uk but stay to the north which why Scotland and Ireland so far have had wet start to their summer 7 or 9 European countries have stated a heatwave to contines in to the new week. uk heatwave end tonight for most of the uk heavy rain and a 10 degree drop i can also warn that there will be a worldwide cooling effect this winter 2010/11 with la nina

@Fireman @Jane #21 #130 Stunning, indeed! Thanks for reposting, Jane, or they would have gone unnoticed.

@Jane: Take this link to HerÃ°ubreiÃ° as a sign of gratitude. Look at the flowers!
http://www.centrum.is/jmj/hitt/kob1.jpg

Fireman, your photos are lovely... I've bookmarked for future contemplation, thank you!

Jane, thanks for reposting, missed first time.

Could that be a second steam plume to the far left on the Mulakot cam? Probably just a cloud but It has been around looking suspicious for some time now. Great blog... I am learning so much!!

Nevermind- looks like a cloud. I'm starting to see things from too much volcano staring. Still a good opportunity to mention how much I enjoy the discussions here!

@Carl

Yes I can. But I'm going to need you to verify the lat and lon for them. I have 65.18N - 16.34W @1.682m for HerÃ°ubreiÃ°, but since I am not from there, I am not entirely sure I have the right volcano. The nuances of the name spelling make me a bit paranoid of doing the plot until I know who is who in the zoo.

And yes, the bushel was full. Now I have to process it.

Weather is beautiful and E geyser plume is huge as seen from Hekla.
http://www.simnet.is/jonfr500/earthquake/vefmyndeyjafjalen.html

@Lurking -
Can you use this map? http://en.ja.is/kort#x=614525&y=514403&z=4&q=her%C3%B0ubrei%C3%B0&servi… It's much better than anything Google has to offer, including getting GPS coordinates from the map. I use this whenever I need to look at something in Iceland.

@birdseyeUSA I have just about finished reading Combined electromagnetic geochemical and thermal surveys of Taal volcano... J. Zlotnicki et al, Bull Volcanol.

Not quite sure what to make of all the ...
----------------

Magnetic quenching of magma, piezoelectric effects, thermal contraction during cooling ... the sun's magnetic field flipping.

Entrainment between the sun's magnetic field and magma plumes? I don't know enough. Hmm..

Could the enhanced rate of spreading in Iceland be an artifact of a reduced rate of thermal contraction as per sub-oceanic rifting? Also read some abstracts claiming that rift activity was very sensitive to availability of thermal flux.

I have no idea as to what magmatic lensing is yet.

@Reynir [122] Some would say that the "shipping forecast" was the most important part. I myself would value the 'sleep portion' but that music is oh so delightful. Strangely it perks me up with a reminder of 'all nighters'. Thank you. :-D

First stab at it. Too late to diddle with getting the depth colors rendered. I will likely flip it on it's side and give you a profile of that nearby swarm from the south and the west.

Bed time now... zzzzZZZZZzzz.....

http://i26.tinypic.com/2hejxwi.png

Hi all;
A fatal flaw was that they failed to have any representative posts ready to go up when the blog went live.

Had they done so, and had the content been surprisingly acceptable, the reception might have been better.

Instead we get this "Hi! Welcome to ShillBlog!" (crickets) and everyone, quite reasonably, expects the worst.

Shall we move to the new thread?

@kultsi @lurking Kultsi's map is just great. Bookmarked it. And your graph, Lurking, is perfect. Now I understand the multiple calderas you were talking about.

@Lurking141 i had an email on this on the 11.06.10 Askja volcano saying new magma is accumlating in plumbing system by a women called Dr hazel Rymer who has been monitoring system beneath the mountain I know that Askja is 180 miles of North of Eyjaf on the same tectonic plate.Last major eruption was back in 1875 which caused a three mile wide crater. also known to erupt every 40 years but stated that Askja activity is not link to the recent activity of Eyjaf

Off to he newer threads - Eric has more new rocks for us. Have just spent way too much time going through this thread after a hiatus, snatching info and graphics for my ongoing 'Eyja technical' collection.
OT@raving97, reynir 22 - thanks, reminded me of a great lovely schooner going by the end of the Rockland breakwater a couple of weeks ago.

21 and 136: thanks Fireman, these are brilliant photos. May I use them with my A level class?

@150 thanks Fireman; I will just show them on the smart board, not store them anywhere or put them on the VLE and of course, I will credit you.

GVP Weekly Volcanic Activity Report for June 16-22, 2010

eklemetti — Thu, 24 Jun 2010 01:41:35 +0000

GVP Weekly Volcanic Activity Report for June 16-22, 2010

The latest news from the world of volcanoes, brought to us by the Global Volcanism Program, USGS and the Smithsonian Institution. They are also brought to us by Sally Kuhn Sennert - and if you have a question for her about her job at the GVP preparing the Weekly Volcanic Activity Report and all things volcanic (and hopefully it won't end like another recent volcanically-mitigated interview).

Some highlights (not including Gorely and Sakurajima):

Ioto (aka Iwojima) in the Volcano Islands of Japan produced an ash plume of unknown height. The volcano has frequent phreatic eruptions and abundant fumarolic activity.
Colombia's Nevado del Huila has been experiencing increased seismicity and sulfur dioxide emissions from the volcano and there may have been some ash explosions. The INGEOMINAS elevated the alert status to Orange.
Batu Tara in Indonesia produced a 3 km / 10,000 foot ash plume - the volcano erupts highly undersaturated lavas such as basanites and tephrites thanks to its position north of the main volcanic arc.
Kilauea continues to impress, with activity at the summit lava lake producing tephra and fresh spatter downwind from the vent.
Soufriere Hills on Montserrat produced a number of pyroclastic flows produced from the collapse of the summit domes. There was also a lahar generated during the week's activity.

eklemetti Wed, 06/23/2010 - 21:41

Big E hasn't finished just yet maybe, the GPS is showing marked upward movement in the last couple of days and to the north.

Webcam for Nevado del Huila here

http://intranet.ingeominas.gov.co/webcam/popayan/webcam_Huila.html

hi all just looking at the oil leak/spill photo on weatheronline.com will this leak affect the gulf stream in the near future if they dont cap it in time

Well, "can" and "will" are two very different critters.

Can it affect the Gulf Stream? That really depends on what you define as "affect." Yes the oil can get into it, and in all likelihood, it eventually will. The question then is how much and what nature the oil will be in when it gets there. (either globules, slicks, particles, or wads of crude)

Can it affect the flow of the Gulf Stream? Probably... but how? Changing the evaporative rate of the gulf so that the heating/cooling ratios are different? Okay... how much change do you need to see an effect? How much does the oil move those ratios around? Does it change the reflectivity of the water? I don't have an answer for that.

I also don't have an answer for how the characteristics of "spume" will change. Yes, "spume" is is a real word. It's the stuff that is torn off of the tops of waves in a storm. The spray/foam and what ever else can be grabbed by the wind. It hangs out in the air just above the sea surface and then falls back into the water. Hurricane researchers argue all the time about how much heat energy is extracted from the spume and given up to the storm. One thing that figures in this idea is that of surface tension. At this point, surfactants come into the discussion. surfactants are substances that change the surface tension of the water. Surfactants are also used in detergent for your dishes to break up the grease and oil so that the water can take it off. Another place you will see them are as an ingredient in dispersants used in oil spills where they do the same job.

How will that affect the spume? Will it make any tropical storms stronger? Weaker? Ya got me. It will definitely have an affect by changing the heat flow into and out of the storms, but good luck figuring out what it will be.

The Nevado de Huila webcam sure is not up to date: it's showing midnight view of last night, and it should be on EDT, about 11:20 AM.

A slight precision about soufriere hills activity. There is no new magma at the dome. The different little collapses of the summit dome were caused by heavy rainfall which provoked the fall of already instable spikes on the summit dome. Many hot point were observed but they were the result of the exposure of still hot magma after the different collapses.

@[5] ...and the reason is: the cam is down. The last view looks a bit like it's being nuked...

@Kultsi (#5)

It seemed to 'time trip' backwards. I "could have sworn" (...famous last words...) it was up to date when I posted the link a few hours ago. Shrug

@Raving [8]

I agree with you! I opened the link and it was showing a good pic of the volcano; now, nothing useful. Well, Murphy was an optimist, as s*t happens even when not thought to be possible.

Seismograph links available in link below.

http://intranet.ingeominas.gov.co/pasto/Principales_volcanes_de_Colombia

@3 and 4:

The Gulf of Mexico primary adverse water quality impacts from the oil spill are intensification of anoxic areas ('Dead-Zones') and physical impedance of oxygen and light penetration at the surface from the oil layer. Surfactants applied at high concentration can form their own ordered-strructure phase (called 'micellar') and float, like bubbles after entraining and dissolving oil. Thus we have very large massed patches of solubilized hydrocarbons forming reflective 'sheens' and floating oil, as seen in this image from the UMBC US Air Quality Blog:

alg.umbc.edu/usaq/images/2010_06_19_OilSlick.png

In early June, the effect of dissolved hydrocarbon biodegradation by bacteria and algae on dissolved oxygen in the water column, at depth and along monitored transects offshore, was reported on the Dauphin Island Marine Lab news blog: very low to zero. That situation has worsened over time and is complicated by changes in surface tension by undissolved and dissolved oil-surfactant phases.

Off-topic: Just at Physorg.com "Tiny clays curb big earthquakes" http://www.physorg.com/news196604550.html

The report cited by Birger above begs the geoengineering question, of trickle injection of water-clay emulsions to slowly 'lubricate' certain fault sections in densely populated urban areas of Southern California that tend to 'jump' because they don't have this clay nanolayer in place.

An interesting article: 'Nanocoatings of clay and creep of the San Andreas fault at Parkfield, California.' (2010)
A.M. Schleicher, B.A. van der Pluijm, and L.N. Warr.

geology.gsapubs.org/content/38/7/667.abstract

Melimoyu to all!

Melimoyo has had increased quake activity since mid march of this year.
Sernageomin has released a special report on Melimoyu volcano due to the last set of quakes that started on the 17th of june with numerous afterquakes. This set of quakes are judged to be volcanic in nature and may be asociated with magma opening a route to refill the chamber. Melimoyu is located in Southern Chile.

http://www2.sernageomin.cl/ovdas/ovdas7/informativos2/Melimoyu/2010/Rep…

http://www.volcano.si.edu/world/volcano.cfm?vnum=1508-052

OVDAS/Sernageomin continues to have the volcano at a raised level of observation.

And with that I leave you all to celebrate Midsummer festival in any way you wish. Since I am a Swede I will drink excessivly, chant strange viking songs about small frogs, dance around a cross with hanging balls, and of course celebrate fertility in a clearly heathen way that would make any ancient barbarian proud.

Remember the MET computer models of ASH.

Computer models DO NOT WORK in complex systems and are open to political manipulation.

http://online.wsj.com/article/SB100014240527487039000045753251311116377…

@Passerby [13]

Oh that just begs for a lawyer (intentionally lower case) to get involved. Supposed that is tried and the stress is relived through creep and a quake happens further up the fault.

Who's liable?

You got the concept wrong. Stress is reduced incrementally along the treated fault line and not passed up the chain because stress-strain energy isn't stored locally to the point of failure, at least not at the surface.

My understanding is that stress is moved downward, deeper into the earth as a result of clay mineral action on faulting surfaces within subduction zones. The farther that energy is located downward (at depth), the less catastrophic the wave energy action at the surface.

Deep earthquakes release more total energy, but releasing it at depth affords a large buffer in overlying strata to reduce transmission to the surface, especially if the surface fractures are made more elastic by the clay particle nanolayer than the deeper and more brittle rock strata in the crust.

Could be a dumb idea, may be impossible to move clay into these layers. It's just an idea, one that I'm reasonably confident has at least crossed the minds of the authors, and maybe reviewers, too.

@Passerby

Okay. I accept that I have the concept wrong.

But I have taken it upon myself to derive some life lesson from every ship that I had been on when on active duty.

Ship one... I learned crisis management. "Grace under pressure" (usually denoted as grace under fire, but no one ever shot at us, so I got that going for me.)

Ship two... It can always get worse, or go bad.

Ship three... Contingency planning. In other words, what are you gonna do when it invariably does get worse?

Ship four... Good luck with the plan. The Universe is quicker on its feet than any plan.

So... despite me having the concept wrong... okay, but I've seen how that works out. :D.

http://www.pia.gov.ph/?m=12&fi=p100625.htm&no=38

Soon it will be level zero and your not allowed to climb or go near a volcano in the Phillipines. Lucky in Indonesia you can actually see the beauty of a volcano and not be hounded by the government

POPO seems to have a nice glow in the pre-dawn darkness.

@Carl #14. Am intrigued by the dancing around a cross with Hanging Balls...this is just before celibrating fertility :) Sounds like a great party!

Someone is posing in front of ThÃ³rolsfell cam!

Are they interfering with tremor plots?

@Marginata [21]

This http://www.youtube.com/watch?v=8I5BGsK5ZAU gives you an idea of the Swedish Midsummer.

@Kultsi 24 hahhaha :) OT: In Greenland for Danish 'Sankt Hans' in the '50's the airfield guys and the mine guys would meet for a 'football' (soccer ) match - and a big outdoor feast - and burn the 'witch' in a big bonfire for good luck. One year we had to cross the river on a D-9 bulldozer to get to the party because the it had jumped its channel and was trying to wash out the airstrip. Big excitement for us kids.

Hello JÃ³n FrÃmann,

JÃ³n I just saw that your Hekla Semicorder was "stuck" at 09:56 but your probably aware of this,

Kind regards, Adrian.

Apologies,slight "brain fade" there.I meant to say Helicorder of course.

IMO seems to have lost their english translation webpage.

Popo is indeed showing vigorous steaming this morning. Worth keeping an eye on it, as it looks like fumerolic activity has erupted on the side of the volcano from a vent.

I wonder what the seismometers are showing.

The tremors on JÃ³n's plot looks suspiciously like cultural noise of Swedes chasing flying hanging balls during surstrÃ¶mmingspremiÃ¤r. Perhaps a few weeks early, no?

http://www.youtube.com/watch?v=CTuUEgjBBEc

@ Kultsi 24 - OT but thank you so much for that clip, it made my day! It looks like a Mad Hatters Tea Party being held on Fancy Dress Friday at T in the Park (big music festival in Scotland early July, cant wait!). Great stuff!

@Passerby

IMO's regular page http://www.vedur.is/skjalftar-og-eldgos/jardskjalftar/ and ongoing spectral tremor analysis suggests that the "noise" is cultural. :)

I didn't mean the IMOs tremor plots, I meant the ones from CENAPRED for Popo. After carefully comparing time series photos for the past 10 days, it appears to be in the early stages of an eruption.

In fact, it's rapidly escalating.

Confirmed.

Fumerolic (steam) eruption. We'll just wait to see if this yet one more large 'exhalation' that are quite common or another small eruption (couple weeks ago). The incandescence visible at daybreak suggests the latter.

Three webcam stations are available
http://www.cenapred.unam.mx/es/Instrumentacion/InstVolcanica/MVolcan/

http://www.cenapred.unam.mx/popo/UltimaImagenVolcanI.html
Excellent views on the Popo webcam.

And while waiting for Popo to ... here is a moonbow http://ht.ly/23idz

In my recent wanderings regarding Taal I found the following document. Wouldn't such methods be good for monitoring subglacial systems such as Katla and EyjafjallajÃ¶kull?

MONITORING ACTIVE VOLCANOES
BY ELECTROMAGNETIC AND OTHER GEOPHYSICAL METHODS

Second Workshop organized by:
The Electromagnetic Studies of Earthquakes and Volcanoes Working Group1
and
The Philippines Institute of Volcanology and Seismology, Philippines2

http://www.emsev-iugg.org/emdoc/EMSEV_PHIVOLCS_2010workshop_20091201.pdf

The glow from Popo was very strong before day break. Lava must have been at the surface. Probably melting the glacier. Nice steam plume

Definite small amounts ash in the earlier pics of Popo around 7:30AM today.

Electromagnetic, geochemical and thermal investigations of Taal volcano, abstract. Jacques Zlotnicki, Feb 2010
(workshop online proceedings, per #37 above, with references)

www.intlvrc.org/EMSEV-2010-3.doc

Steam plume continuing to increase in elevation and volume.

@Passerby
They've also changed the refresh rate for the cams on El Popo - seems to be every 30 seconds, instead of the one minute they state in the caption.

Very active, I'd say, just short of an eruption.

tinyurl.com/23dweqz

#38: Sorry to be the bearer of sad tidings, but the is no glacier on Popo. Done bit the dust due to recent eruptions. Good read:

Impact of the eruptive activity on glacier evolution at PopocatÃ©petl Volcano (MÃ©xico) during 1994â2004. (2008) Julio-Miranda et al. J. Volcan. Geothermal Res. 170:86â98.

Excerpt from the abstract: The glacier evolution and subsequent extinction were induced by the eruptive behavior over the years. While not the only process at work, eruptive activity played the primary role in accelerating
retreat and as a consequence in glacier extinction.

http://www.geofisica.unam.mx/popoc/colaboracion/GTNH/files/public_mexic….

Nice find, Raving.

@Passerby (#44) Your link has been 4Ofnord

http://smsc.cnes.fr/DEMETER/

*gasp*

Remove the period at the end of the pdf hyperlink.

It's the authors manuscript copy. There is a previously published related publication, 'Glacier monitoring at PopocatÃ©petl volcano, Mexico: glacier shrinkage
and possible causes.' (2003) Huggel and Delgado.

www.geofisica.unam.mx/popoc/colaboracion/GTNH/files/public_mexico/03Hug…

I have an NASA EO satellite image from February 2009 showing the glacier remnant.

earthobservatory.nasa.gov/IOTD/view.php?id=37589

Umm,Eyja is giving Popo a run for her money at present.

Some assembled video of today's activity at VolcÃ¡n PopocatÃ©petl

http://img204.imageshack.us/img204/4999/poa.mp4

I was just thinking when a storm reaches the oil spill. just think how much oil the storm would pick up and hit landfall. Then rain on to the roads, then the roads become slippery?

http://translate.google.com/translate?js=y&prev=_t&hl=en&ie=UTF-8&layou…

Whoooooops

Thanks for spreading the word about this.

Monday Musings: Russian activity, tremors at Ngauruhoe and Mayon climbers beware

eklemetti — Mon, 21 Jun 2010 00:20:18 +0000

Monday Musings: Russian activity, tremors at Ngauruhoe and Mayon climbers beware

News for Monday!

Ngauruhoe in New Zealand, showing the dark lava flows of basaltic andesite on the slopes of the young volcanic cone. Image by Erik Klemetti, taken January 2009.

A couple pieces of news from two Russian volcanoes on the Kamchatka Peninsula: (1) last week's report of activity at Gorely appears to be semi-substantiated with new photos on the KVERT website (Russian). The images from June 6 and 12 (2010) shows steam plumes coming from the volcano - one as tall as 500 meters. Now, this doesn't imply that an eruption occurred, but it might suggest activity on on the upswing. KVERT continues to list the Alert Status at Gorely as "Green". (2) An eruption over the weekend at Shiveluch produced an explosive plume that reached 4.5 km / 15,000 feet. Over the last few days, the volcano has experienced over 150 earthquakes, but the activity is no threat to nearby villages or aviation over the peninsula. The status at Shiveluch remains at "Orange".
On the other side of the Pacific Ocean, there are some interesting tremors (Updated 6/21/2010: Nope, likely these "tremors" are just wind in the area of the webicorder - see the comments below) going on near Ngauruhoe in New Zealand. This fairly active volcano is part of the Taupo Volcano Zone and is located next door to Ruapehu near the famous Tongariro Crossing. Now, there is no indication on the New Zealand GeoNet website and the status is still "green", but it could be something to watch. Ngauruhoe last erupted in 1977 and had frequent eruptions in the middle of the 20th century. Ngauruhoe is really the youngest cone of Tongariro volcano - a cone that started forming only 2,500 years ago. The volcano tends to have strombolian explosions with basaltic andesite lava flows (see image above) ... and be sure to check out the Ngauruhoe webcam.
Over in the Philippines, government officials now have the deal with tourists visiting Mayon instead of Taal after they were warned to stay away from the latter volcano. However, dangers still exist at Mayon, where there are frequent rockfalls and small explosions - yet tour guides still bring people into the 6-km exclusion zone. Although the Alert Status at Mayon is at Level 1, the crater still glows red at night, reminding us that magma is still near the surface.
Finally, last year there was a lot of talk about the oil storage tanks near Redoubt in Alaska. This week, the Cook Inlet Regional Citizens Advisory Council heard a report on the storage tanks and whether the CIRCA did an appropriate job in planning for a volcanic eruption from the Alaskan volcano in regards to the potential spill from the tanks. More or less, it appears that the Council may have been complacent in the oversight of the facility - a common problem when it comes to planning for disasters.

{Hat tip to Eruptions readers M. Randolph Kruger and Bruce Stout for information used in this post.}

eklemetti Sun, 06/20/2010 - 20:20

Which tremors for Ngauruhoe do you mean, it looks like it's only had two earthquakes in the last few months, is it the smaller tremours? http://www.geonet.org.nz/images/volcano/drums/ch/otvz/10/drum.png

http://www.geonet.org.nz/volcano/activity/ngauruhoe/index.html

This is great news, I've been waiting for this one to erupt for ages. Last year when I climbed it last year it only has steaming out a few fumaroles at the top at the side and inside the main crater nothing was steaming at all. NZ has been pretty boring of late, I wish something would happen there.

Greg: Be careful what you wish for, especially when talking about eruptions!

Thanks for the info about Mt. Ngauruhoe, Erik. I'll check the webcam when I'm not at work :-)
I did the Tongariro Crossing in 2000 and vividly remember the blue and green crater lakes up there.
As there are many tourists up there every day (at least in summer) I would not wish a sudden eruption or bursting crater lake rims...

I wonder if Ngauruhoe isn't just celebrating the "Victory" of the all whites against Italy yesterday. I guess a volcanic victory dance would be a bit tremorsome:)
And let me just say that for a swede Ngauruhoe is definitly on the list of un-pronouncable volcanic names. Give me something easy like EyjafjallajÃ¶kull any day!

Ngauruhoe is a very beautifull volcano, would look stunning with a nice strombolian eruption, especially since it dont have any ice-cap on top. Hope there are a lot of webcams around! One that up-dates every 30 minutes would be a bit disapointing. A live feed from a few angles and a FLIR for night-time would be good, microphones so one could put it on the speakers, and of course live helicorders so I could feed my finally finished actuating chair... Then it would just be to fire up the videoprojector and pop a beer:) Would beat the Football worldcup any day.

A question:
Is there anywhere one could get translations from the Indonesian volcanic centres updates? I've tried to look but haven't found any on their site. http://portal.vsi.esdm.go.id/joomla/

Would be nice to see if something is brewing there since they do have some of the nicer volcanos around.

Thank's in advance for the avalanche of help that I know will be coming from the knowledgeable pros here!

@Carl #5 Try using the Google Chrome web browser. You can get all sites translated to the language of your choice. It automatically detects the language and you may choose to which language you want the article translated. I would advise you to choose English - you know, as for Portuguese you may get very funny results. I tried the link you posted (thank you for that) in English and it worked fair enough. Of course it doesn't work for images.

On HvÃ³lsvÃ¶llur cam steam plume is visible now. Lady E is still giving signs of life.

#2 as long as lake Tapou or Auckland field doesn't erupt it will be ok. That Ngauruhoe climb really makes you fit lol. And the weather coming in and out and crampons at the top made it lots of fun too. Ruapehu's crater lake softly churning actually looked more creepy :P

not sure if intrested or not, but found this site not sure if its fake or not. National Association of radio-distress signalling and infocommunications,Emergency and Disaster information services {EDIS} havaria@rsoe.hu or zsolt.boszormenyi@rsoe.hu this site shows all the current volcanoes and earthquakes ect.

@ Greg (and all) - Ooops! I somehow forgot to add the link for the Ngauruhoe tremor. I've updated the post above and you can see the webicorder for Oturere (Ngauruhoe). Sorry about that.

Hi, what sort of tremors are they, harmonic?

Greg: well, I was thinking more about Taupo et al. Or Taranaki, which is statistically more likely to reawaken soon than either Taupo or Auckland. Re Ngaurohoe; I've got an interesting book ('Hot Water Country' by Ross Annabell) which has some lively anecdotes about it. Published in NZ, I think, so it's on your patch, I'd guess

Here's Thorvaldseyri's new website, the early 'farm under the volcano' - http://www.thorvaldseyri.is/ Wish there were an English version, but hey...

birdseyesUSA.comment13, It can be in english just click on union jack top left side of the page

Anyone else pondering what this cluster of eq's under Lady E might mean?

http://en.vedur.is/earthquakes-and-volcanism/earthquakes/myrdalsjokull/…

Though, admittedly they are very shallow.

@12 Would be nice if White Island fired up, apparently it's thrown rocks 50km to the mainland before lol

Greg 12: Is White Island still privately owned? (It certainly used to be). In which case lawyers would have a field day if it caused damage on the mainland LOL

Sorry, that should have been to Greg 16

@birdseye, #13, There is an english version of this page, and as far as I have seen, it contains all the info of the icelandic page.

@Laura from Canada [15]

Dunno, but here is how they look in profile. Quakes from 6/16 to 6/20.

http://i45.tinypic.com/34g3cow.png

Hi to all,

Birdseye @13,Hi I just checked out the Thorvaldseyri website.On the main page at top left there are Icelandic and English flags.Click on the English flag and it all becomes much clearer !
Laura @15.Curious little swarm that,and no real depth to any of them.Umm,we will see.

@14,19,21 ...and I just got new glasses ...sigh.....lol, thanks! ;

Not sure if it's anything, but a curious darker cloud is rising on the far left of the thoro cam... and someone just walked by snapping pictures.

And by far left, I of course me far right.... lol

Ngauruhoe is still fast asleep. Doesn'nt look like volcanic tremor at all. Climbed it last year, it could use a new eruption though, the slopes ar getting very eroded by all the people climbing it.

Guys,
I'm 99.9% certain that you're observing wind on the Ngauruhoe (...and other NZ volcano seismometers)! Remember it's winter now down there. If Nguaruhoe,..or any other volcano was producing the observed ground motion, bells and wistles would be ringing off their mounts. Seismometers don't just record volcano-genic stuff,...I've seen helicopter passes on the Ruapehu seismograph from time to time.

Rodger

@ Ber - Yeah, I'm not sure what to make of the noise on the webicorder. Any thoughts from the tremor-hounds out there?

Question: The last I looked Redoubt had been removed from the larger Holocene eruptions list, anyone know why? Here is a copy/paste from when it was there.

http://www.volcano.si.edu/world/largeeruptions.cfm

Name - Location - Date - Volcano Explosivity Index

CHAITEN Southern Chile 2008Â Â MayÂ 2Â VEI 4 OKMOK Aleutian Islands 2008Â Â JulÂ 12Â 4? KASATOCHI Aleutian Islands 2008Â Â AugÂ 7Â 4
REDOUBT Southwestern Alaska 2009Â Â MarÂ 22Â 4
SARYCHEV PEAK Kuril Islands 2009Â Â JunÂ 11Â 4

Didn't Redoubt erupt 16 times with plumes over 12 miles high, or am I mistaken?

Garry Hayes over at Geotripper has some lovely shots taken of Kiluea from the ocean-- empty lava tubes, pahoehoe and aa lava in unusual formations==

http://geotripper.blogspot.com/2010/06/where-i-wish-i-wasunique-view-of…

Hello Everyone,. :))

just wonderin if "EyafjatlajÃ¸kutl" has a new eruption, it seems like the plume has become a little darker and goes a little bit higher up than It has been the last days(weeks)??

btw a young customer at my store was just uber cute today and asked me if the volcano was still volcanoing on Iceland,. heheh. She was only 7 years.. aww I tought it was cute,.

@Thor,Hi,its a little hard to say at present;too much cloud,but there was quite a large plume earlier re Laura @23&24.

@Thor and Adrian, the recent eq swarms might point to something POTENTIALLY stirring, but alot of them were very shallow. I'm questioning though the lack thereof any real tremor movements. I'm pretty sure I saw a plume, but there was some cloud cover (and some very dark clouds) so it could have been that. Just thought that it was ironic that when I saw it, someone else ran by the camera snapping pictures. ;)

@Thor

I don't think anything is going on in the way of an eruption right now - but a flood might be in the program, and you can never bypass explosions as long as things are as hot as they are now. The greatest hazards now are, in my opinion;
1) renewed eruptive activity in the current crater with extremely violent interaction vith the water there
2) no eruption, but a breach of the crater rim releasing all the water trapped in the crater and the jÃ¶kullhlaup down GigjÃ¶kull following that

A nice approximation of the pronunciation of EyjafjallajÃ¶kull, btw - although the Norwegian/Danish version of 'Ã¶' (Ã¸) might throw some people.

Ed 28: I think the Redoubt eruption plumes reached 12km, rather than 12 miles, which is a big difference! Also the VEI rating is calculated on more than just plume height; it certainly includes the total volume of lava/tephra produced in the eruption, and the 2009 eruption was no bigger than (or maybe slightly smaller than) the 1989 eruption in terms of volume..and that was a VEI 3

Kultsi :))

Hi,..

I was just checking on the Metrolocial pages
http://en.vedur.is/earthquakes-and-volcanism/earthquakes/myrdalsjokull/
and there has been more activity,when it comes to shallow quakes then it has been for days/weeks,.
maybe its because of the ice/water melting and running into the crater and down the plumbings inside the mountain??

If you warm up mountain and then add cold water on it it cracks and breaks so maybe that makes the quakes??

anyways there is something going on up there,
and I agree with you

1) renewed eruptive activity in the current crater with extremely violent interaction vith the water there

2) no eruption, but a breach of the crater rim releasing all the water trapped in the crater and the jÃ¶kullhlaup down GigjÃ¶kull following that

These scenarios will both be diastrous, and extremely dangerous.

Remember that

EyjafjÃ¤ll, has had longtime eruptions that has had on /of breaks in between the eruptions, somtimes longer breaks and other where shorter..
if the water mixes with lava then things will sure become nasty for a while and quite explosive..

and Im sure the eruption on "EyjafjatlajÃ¶kutl" is not over,its just in another fase before starting up again..
and I wont be surpriced if another Volcano will erupt in the meantime, no im not sugesting Katla, that eruption might take some time before starting.. but will sure come with time..

birdseye @ 13, thanks for the link to farm photos. From that, I found a link to more Ejya. photos: http://www.nordicphotos.is/IS/search/Eyjafjallaj%C3%B6kull The April 14 distance shot of the farm with ash and steam plumes behind it is one I'd be tempted to buy, but I don't see how to find prices. [ http://www.thorvaldseyri.is/skrar/image/Gos_i_Eyjafjallajokli/DSC08496… ]

Oops, this is the purchase site, but it's only in Icelandic, as far as I can tell. http://www.nordicphotos.is/IS/Details/6710791

@ Roger, 26

wind noise was what I thought of first too so I checked nearby seismograms to see if there was anything unusual but they looked normal to me (I check the geonet seismograms out everday) and, knowing the volanic plateau, high winds are more the norm than the exception, so this would mean a really exceptional storm to generate such a localized signal. On top of that, I haven't seen the graph look like this before in over, at a guess, two years of following it. That's why I mentioned it here.

OTOH Geonet haven't mentioned anything at all on their site or bumped up the volcano alert, so I guess you're right. There must be some extraneous source for the signal. Maybe they moved it or some tourists are having a party or something.

@Thor, @Adrian @Laura: Definitely there's a darker plume. Clouds are coming and going, but keep checking on ÃÃ³rÃ³lsfell and MÃºlakot cams. A pity that I must leave now.

http://www.icenews.is/index.php/2010/06/20/glacial-flood-in-south-icela…

Flood in Iceland.

Where is the seismograph in NZ, since when we climbed Mnt Doom it was Novemberish and there heaps of ice on it, so now there must be a lot of ice on that mountain. The weather really came in and out all the time and we had a few white outs. Yeah it's overdue for an eruption since before the 1970s it erupted pretty regularly. There is an old worn out sign up from NZ Geo about "toxic gas" inside the crater and not to climb in, I think it was stirring a bit in the last 10 years but has been really quiet and boring lately. So hopefully it wakes up, since it's erupts differently to it's giant neighbor.

@17 Yeah I think White Island is still private. Arises from the sulphur mining that used to occur there, until one day all the miners were gone :P

As Rodger says, I don't see any tremor at Ngauruhoe, only the usual mid-winter weather. It often looks like that on windy days. Sorry to disappoint!

@41 nooooooooooooooooo I want NZ to go active, so I don't have to fly across the planet to see active volcanoes :P

@ 41 mfs.. Thanks for the feedback. Just by chance, mfs, it sounds like you and Rodger know what you are talking about. Personally I would love to hear more about NZ's volcanoes if you are, um, closer to the source (perhaps not a very apt thing to say when I think about it) e.g. do you have any info about the small swarm under haroharo ? etc.

BTW, I'd still dispute the claim that it often looks like that on windy days. Raoul often looks like that, but as I mentioned above, just about every other day IS a windy day on Ngauruhoe and I honestly haven't seen it look like that before. I am not saying it is tremor (as otherwise Geonet would have issued a statement) just... well I guess I am just trying to save face by tripping over backwards. ;-)

Hi Bruce,

The gain settings (amplification) on each of the NZ volcanoes appears to be different (perhaps according to their levels of activity and also according to their sensitivity to wind, cultural noise, etc). I've watched them for a while as well. Since Ngauruhoe was showing some seismic activity the past few years, I take the GNS seismologists have that station running alittle "hot" so they don't miss anything. If you watch activity at Tongariro vs Ngauruhoe (which is actually a parasitic vent of Tongariro) you'll see what I mean. A good test of their sensitivity is to find a regional earthquake on all the seismograms, and then find out where it occurred in relation to each station. Typically, the regional event will be well recorded on the Ngauruhoe station and rather weak on the nearby Tongariro station (If the amplification of both stations were identical, a regional event should appear nearly identical in size and with similar waveforms).
If you want to see what tremor looks like at a NZ volcano, keep an eye on White Island. There is usually low level tremor there which ebbs and flows over time, sometimes grading into discrete low-frequency earthquakes,...saw that last month in fact!

Rodger

Thank you to everyone who helped clear up this Ngauruhoe webicorder noise observation - I've updated the post to reflect the consensus that it reflects wind in the area. Good to keep us on our toes, eh?

Bruce @ 43,
I might be closer than you but still pretty far (Tasmania). I spend a couple of weeks working in NZ most years and have been keeping a regular eye on Ngauruhoe since the earthquake swarm that happened a couple of years ago. I remember seeing very thick traces quite often in the past and it's always been attributed to weather. Just like Taranaki seismometers used to be near the North Egmont park entrance and showed road traffic noise regularly during opening hours.
If any new activity occurs, the Geonet website is usually pretty much on the ball and issuing alert bulletins at short notice.

I wouldn't be too concerned about that Gorely volcano. It sounds like a girly volcano to me.

Profile View of Eyj/Kat quakes 19th to 21st.

http://i50.tinypic.com/ncicqu.png

Zoomed in Plan View, same color codes for depth, Eyj only. Shows a good layout of the shallow quakes.

http://i45.tinypic.com/mq2k3.png

Ref my last [48], the 2nd graphic has a "Kat" label, ignore it. I forgot to yank it out when I slewed the graph to the plan view.

@49: Thanks, Bud!
Deep pressure continues from below.

Eyjaf eruption rolls along at low throttle. Surficial EQ from peripheral icecap melting and steam flashing with gas bumping.

And.. since I'm doing a slight hiatus from the Oilcano...

15 Minute Quake energy (all quakes from en.vedur.is/earthquakes-and-volcanism/earthquakes/ site, updated to 22 June.

http://i47.tinypic.com/qoevrc.png

Mike @34 Hi, I'm big into the effect volcano eruptions have on weather intensity and cloud formation.

According to this write-up by Joe D'Aleo of http://icecap.us/ fame...

http://www.intellicast.com/Community/Content.aspx?a=223

Redoubt blew over a dozen times to 60-65,000 ft plus and that calculates to 12+ miles.

I keep seeing other climate related data being altered or even hidden by certain agencies, won't go into that, but I'm just plenty curious. For example, much of the past raw Zurich solar cycle data at NASA now cannot be retrieved. Redoubt is suddenly missing from the Smithsonian Holocene list... like what's going on? I want to know. Thx

Love this blog btw!

@Ed Murphy[52]

Have you tried SIDC as an alternate source of Solar Cycle data? It's the Royal Observatory of Belgium and is sort of responsible for keeping a tally of some of that data.

sidc.be/index.php

Kp and AP indexes can be found here : www.ngdc.noaa.gov/stp/geomag/kp_ap.html

And, if you want to see something really stupid...

http://i49.tinypic.com/i39wlt.jpg

This is a plot of the end of Cycle 23 and the start of Cycle 24. According to SIDC, the cycle began on 12/13/2007 when the first reversed polarity spot appeared. The red line is the monthly SSN of an average cycle (derived from the previous 23 cycles at that particular month in the cycle) and the yellow traces are 1 standard deviation above and below that value. Theoretically, 64% of the time whatever monthly SSN you happen to have should be between the two yellow curves. (standard deviation was also derived from previous 23 cycles)

Eh.. it's late. Sorry for the OT.

Has Mount Egmont had any tremours over recent time, that one is long overdue. Beautiful shape with the flat plane around it. And that volcano is out of line with all the others in the North island system

Thank you Erik for the kind words.....

Thank you for this webpage. Thats all I can say. You most definitely have made this blog into something speciel. You clearly know what you are doing, youve covered so many corners.thanks

Beautiful photos. Thank you for this writeup, I am a law assistant professor in Iowa and I found this to become really helpful.

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Allezeit gelangen nagelneue Telefone auf den Marktplatz. Aber wie einwandfrei sind diese ?

Dauernd erscheinen nagelneue Telefone auf den Gebiet. Aber wie nÃ¼tzlich sind diese ?

StÃ¤ndig erscheinen erneuerte Mobiltelefone auf den Markt. Aber wie einwandfrei sind diese ?

I feel that is a fascinating point, it made me think a bit. Thank you for sparking my thinking cap. Now and again I am getting such a lot in a rut that I just really feel like a record.

I think that is an enchanting point, it made me assume a bit. Thank you for sparking my thinking cap. Now and again I get so much in a rut that I simply feel like a record.

GVP Weekly Volcanic Activity Report for June 9-15, 2010

eklemetti — Thu, 17 Jun 2010 05:54:30 +0000

GVP Weekly Volcanic Activity Report for June 9-15, 2010

Have guests in town, so I'm a little busy, but you can hopefully keep entertained with the latest Smithsonian/USGS Global Volcanism Program Volcanic Activity Report.

Chile's Melimoyu volcano.

The highlights (not including Taal and EyjafjallajÃ¶kull) include:

Alaska's Cleveland volcano has been reduced to and alert status of "unassigned" (used when a volcano is not closely monitored so AVO doesn't know what exactly is "background") after a few weeks of activity. The same was done for the submarine volcano south of Sarigan in the Marianas Islands after no signs of activity since the eruption a few weeks ago.
Chile's Melimoyu has seen increased long-period seismic tremor over the past week, enough so that the SERNAGEOMIN increased the alert status to Green Level 2. All the earthquakes are less than 15 km underneath the volcano, but no other signs of activity were noted in the report.
Karymsky, on Russia's Kamchatka Peninsula, continues to make noise, with ash plumes reaching 2.6-6.1 km (8,200-20,000 feet) and a thermal anomaly at the summit.
Eruptions readers have been talking about the recent activity at Japan's Sakurajima. The volcano experiences frequent explosions and this week produced ash plumes that reached as high as 3 km (10,000 feet). You can check out the activity on the webcam for the volcano.

eklemetti Thu, 06/17/2010 - 01:54

There seemed to be a lot of steam venting from Sakurajima earlier today, nicely captured in time lapse video before the rain clouds moved in. That's the first time I've seen so much steam coming out.

Spot the little bird too curiously checking out the camera at 1:55!

http://www.youtube.com/watch?v=k2lJNRQDpZ4

Nice video, James - looks like the bird has a nest there somewhere? :) Looked like a couple of little explosive events at the side vent, too.

http://www.gmanews.tv/story/193768/tv-reporter-trapped-in-taal-volcano-…

Nanny State allows silly media into Taal, and they get trapped because they can't climb LOL

Again, I have to ask, what does this article you (and I) linked about the TV reporter have anything to do with the so-called "nanny state". The article pretty clearly states that the reporter went out of his way to get into trouble.

Personally, I don't think Fran Dresler had anything to do with the reporter...

*ducks :D

Good thing Taal didn't go off right then.

Headline should read: Reporter gets himself into trouble in Taal Crater.

Well the Nanny State let the reporters go in. They were allowed to go where others were not allowed (ie the Island), but then they went even further, climbed down the ridge and get stuck for 5 hours only to be rescued by coast guard. If they care so much about safety they should have banned them, especially after the Guatemala incident.

So foreign nationals are banned, but their trusted reporters are ok. And look what trouble reporters get in. I recall the only people to get killed recently in South America was a CNN reporter (+ his guides). So really the people most at risk are the reporters, since they want to get too close, as they have financial gain in doing so. So reporters are the ones that should be banned, not experienced tourists who visit lots of volcanoes. :P

In Guatemala the reporter and his guides were killed...

http://edition.cnn.com/2010/WORLD/americas/05/28/guatemala.volcano/inde…

@Greg [7]

"... So really the people most at risk are the reporters, since they want to get too close..."

That's more of a natural selection effect rather than anything having to do with some sort of state organizational structure.

I just don't get why at Level 2 it's so restricted. At Mayon it was level 3 when real restrictions began to happen. There has been a massive shift in restrictions in Philippines for some reason?

But considering what happened in Guatemala the government should keep a close tab on journalists. You only have to search you tube to find lots of videos made by journalists sneaking through areas when it is actually really dangerous. They want to get too close, since they want to make big money getting that winning shot.

If the whole thing was really going to blow, why are people still living on the island near to the volcano, as that's where the journalist was given initial permission to interview, since it's not really that far from the crater. And who'd be stupid enough to go down to the water by yourself from the viewing deck. Did he want to go for a swim lol?

I don't think it would make much difference if you were on the ridge or 5km away if the whole thing was really going to blow. If level 2 is so dangerous then a 20km exclusion zone should be made.

Remember, the Alert Status is only part of the equation. The landscape and population around Mayon and Taal are very different, so you actually wouldn't expect that preparation and closures would be the same at the two volcanoes. I think that the Philippine government is approaching this with an abundance of caution, which is fine with me. If not and people die, then we can all enjoy the scientists getting sued for not "predicting" the eruption correctly.

Each "state" (whatever sort of governmental you wish that to express) has finite resources to deal with emergencies. Not all of them have the same resources. Not all of them wish to endanger rescue crews who had better sense than to place themselves in danger for the sake of a photograph or an "ooooh, ahhhh" experience. A "state" has to weigh it's resources and chances at pulling off a successful evacuation with the probability that something bad happens.

I can't speak for anyone else, but I would be pretty P.O.'d if as a rescue worker, had to go retrieve an idiot rather than rescue a displaced family. The family didn't ask for the problem, the idiot who fell into the hazard area for the sake of a photograph did. Let natural selection take it's course. I'll go help the family.

Greg, if your idea of a "Nanny State" is the Philippines government then heaven forbid what you think of any western government with their health and safety regulations etc. Do you live in the Philippines?

In Guatemala it was actually a local reporter who died, he worked for a local CNN affiliate.

I've been fortunate enough to meet both Renato Solidum (PHIVOLCS director) and Ed Laguerta (resident Mayon volcanologist.) They're both very highly regarded and in my discussions with them they took protection of lives as their number one priority - can't fault them for that!

Meanwhile a nice steam plume on Eyja from HVOL cam only, too cloudy otherwise - being blown toward THORO cam so it looks as though it's steaming at the top of GigjÃ¶kull too.

There is a new report about Melimoyu in the OVDAS page, talking about a VT quake occured today (june 17th). I don't know if all that green alert (only preventive) and this report is due to real hazard of a possible future near eruption or because the volcano has a seismic network from a little time ago, and it is necessary to 'know' it.

Two EQs under EyjafjallajÃ¶kull, one not so shallow, and JÃ³n Helicorders showing interestingly active plots earlier today.
Now the plume shows an interesting grayish hue.
Definitely, she is not done yet.

Why I do believe we have a new troll here - a 'Nanny State' troll. Greg (or whoever he is) knows that using this term in his pathetic posts will push buttons and get him attention.

>>>>Do not feed the Troll<<<<<<

Hi all,
I have such a basic question that it might seem silly but here it goes:

On the charts at

http://hraun.vedur.is/ja/gps/predorb/theypred.html

will the upper-limit on the chart be adjusted if inflation increases beyond +20? After staring at it for so long, this is the first time I've noticed the reading this high.

Thank in advance!

#17 cont'd - on the North chart, that is.

Shiveluch has to be feeling smug after getting its name dropped in yesterday's news on RÃV.

Hi, life kept me busy, but i finally came across uploading some images of ash samples sent by JÃ³n FrÃmann JÃ³nsson on June 2nd.
http://www.flickr.com/photos/arselectronicacenter/
my personal favorite is
http://www.flickr.com/photos/arselectronicacenter/4711578214/in/set-721…

Hello to all !

@20 Birgit,

The sample photos are astonishing.Well done for all your hard work and for bringing them to us.And to you Jon Frimman for sending the samples in the first place !

Yep Erik, Melimoyu has increased the earthquakes since the last 8.8 Earthquake ... It has had more than 257 earthquakes, and yesterday (17th June) SERNAGEOMIN uploaded another Report about more earthquakes that happend that day...
One of them was 3.4 Magnitude, and 8 kms deep. It was produced by rock-rupture as they said.

I was going to Inform you about Melimoyu past 9th June, but I had no Computer
Anyway, Anything I would know i will tell you

Greettings

Excogitate your feel and bury this disarray

Playing the waiting game at Taal

eklemetti — Thu, 10 Jun 2010 08:50:19 +0000

Playing the waiting game at Taal

A partially-eroded scoria cone in the Taal volcano caldera.

As I mentioned earlier this week, PHIVOLCS has raised the Alert Status at Taal in the Philippines to 2 (out of 5) after increasing tremors and gas emissions from the volcano's crater lakes. Now, the Philippine government is taking this threat very serious, sending divers, helicopters, rescue equipment and medical teams to the area near the volcano in case an eruption occurs. Provincial officials in Batangas have asked 5,000 people living near Taal to voluntarily evacuate - however, as with many evacuations, people are reluctantly to leave their homes and animals. In fact, a member of the Batangas Provincial Disaster Coordinating Council thinks that many people won't leave until Taal is on Alert Level 4, citing that few people evacuated during that last threat of eruption in 1991. Schools have no closed, either, in the area near the volcano.

Members of the Philippine Coast Guard did venture to Volcano Island - the current main vent area for Taal - and noted discolored water, the smell of sulfur and area of hot water in the lake. These would all seem to be signs that something is brewing under the lakes in Taal's magmatic system - however, passive degassing underneath the lakes occurs all the time (video) in the form of carbon dioxide seeps. PHIVOLCS has not issued a new status update for the volcano on their website, however, Director of PHIVOLCS Renato Solidum Jr. says that the main crater area on Volcano Island is off-limits due to the threat of steam explosions and toxic volcanic gases. The Red Cross is also reminding people of what to do if the volcano were to erupt - in all, it sounds like officials in the Philippines are getting ready in case Taal does spring back to life.

eklemetti Thu, 06/10/2010 - 04:50

Tags

Mt. Rainier WA US ice quakes first since 1998

http://www.spokesman.com/stories/2010/jun/10/mount-rainier-shaking-tiny…

The large avalanche Sat. caught 11 climbers in different groups and couple of solos but one still missing - climbers didn't check-in for risk but were lucky to have some guide groups who did check conditions in a safer area but leaders of groups close enough to dig out 10.

Eyj perhaps with "ice quakes" knowledge we'll learn high risk quakes that mean awakening volcano activity.

Hello all!

Taal has some rather nice features that might give all some good oportunities for speculation. Let's say that it starts off with a rather small eruption in the cindercone volcano that purportedly is the worlds smallest volcano (mini-taal). That would give us all the chance to speculate endlesly on whether and when the larger volcano on Volcano Island (medium-taal) will go off (and at the same time give people the chance to run for the hills). And when the larger Volcano Island (medium-taal) has erupted we can start speculating about if the Caldera (XL-Taal) will go off, for the sake of the locals let's hope that doesn't happen, for the hills aren't big enough to save them really if you run up them, the place is quite simply to crowded and the volcano to big for them all to get away.

OT - warning, stop reading if you are not a full-blown volcanocamoholic!!!

While waiting for that I have started to convert my couch with some rather nice actuating servos (think theme park chairs here) set to work in the 1 to 5 herz region.
I tried it with an algoritm interpreting JÃ³ns helicorder and it worked out splendidly earlier today. Got myself a rather good nether-part massage from the tremors a few hours ago.

That combined with some high res cams on the projector and a big keg of beer, who need's any Football worldcup championship? (For those of the american persuasion; I am not talking about american soft-rugby here, I'm talking about what you strangely enough term soccer.)

Only problem with my coming ascension to Nerdhood is that 2,4 herz is the worst vibration possible to shake yer bubbles out of the beer... Something my company notised after installing it for the first time at a theme park serving beer, it all became known as the Summer of Burpy Vegas:)
Before that it had only been installed at beer-free Disney-parks, and kids always burp of cola so nobody noticed...

And now back to the waiting:)

@2 Carl LOL! Why not add another projection for footie? It's online on multiple stations around the world. If I could do it, it would be a nice memry to add to my collection of watching the world cup in bars around the world....

I am very much learning, but have been looking at the situation in Iceland.

There seems to be a lot of seismicity ongoing in two regions, apart from Lady E, and I wondered if any of you could clarify if the ongoing swarming of earthquakes around Hengill area,
http://en.vedur.is/earthquakes-and-volcanism/earthquakes/hengill/

in a fairly fixed location over the last several weeks and this large EQ bump (before it disappears off the time scale) means anything?

http://hraun.vedur.is/ja/oroi/oroakort.gif

While there has been lots of seismicity around Vatna, it seems to be spread out along the fault line, whereas this lot near Hengill seems quite fixed in its specific location. What, if anything, does this tell us?

Many thanks for your help.

Beautiful views in all cams. Can see ice clearly on Thorolsfelli for the first time in a long while.

Local seismicity could be related to drilling at the Hellisheidi Geothermal Power Plant, the largest in Iceland and one of the biggest developed geothermal complexes (in conjunction with Nesjavellir geothermal energy operation) in the world. It's locoated ~10 Km to the north if the concentrated EQ focus you observed.

greenerenergyblog.com/2009/01/13/hellisheidi-geothermal-power-plant-%E2%80%93-iceland%E2%80%99s-newest/

There is also the Icelandic section of the International
www.icdp-online.org/front_content.php?idcat=709
Deep Drilling Project, with wells to 5+ Km, with the goal of capturing geothermal energy under supercritical conditions. News on drilling and well tests have been bit lacking since Sept 2009/

Typical wells at Hellisheidi are a couple Kms in depth. is just completing the final planned phase of incremental geothermal power development of the site, although there is talk of adding even more generation capacity later on.

Not saying that the EQ activity is directly related to the geothermal complex operations, but it could be indirectly contributing by augmenting tectonic stress loading in a very active fissure/fault area.

Hi, We just had a Spezial DeepSpace Live on Eyja and its ash in our museum Ars Electronica Center in Linz. I was allowed to talk 15 mins and told the story how people on this blog followed and are following this and other eruptions. I praised this blog, its host and all the cool people here as good as i possibly could. I learned so much here and i told my visitors they can do that too, from their couch at home they can see what the volcanoes of the world are up to at the moment. From the comments i got afterwards, .. people really enjoyed the show and many said they are going to check this place out.
Something else:
Jon Frimann ( i still dont know where to find the `above the i and o on my keyboard, sent me ash again on monday and i did scanning electron microscope images on the 3 different samples again. I will upload some on the ars electronica flikr acount on monday. Jon Frimann already has all the images i did ( on tuesday) As soon as i am done i will post the links to the albums here again. ( But only the best ones, the album is getting too big. At the moment you can only find my pics from some weeks ago on flikr.

sorry for the x-post, I put it in the wrong thread.
From the Library of Congress: the original report on the 1911 eruption of Taal by Reverend Miguel Sanderro Maso of the Weather Bureau. It's a big file but fantastic read.
http://ia340935.us.archive.org/1/items/eruptionoftaalvo00philrich/erupt…

@Birgit - You apparently had no trouble in producing the grave accent (`), which is not the one used in Icelandic, it's the acute one (Â´) we are interested in.

At least on my keyboard - and on a German one - the accents sit right beside the backspace key, and using them for accented letters is simple: you press the accent key and the one you want to put the accent on right after the other - in fact, to produce the individual accent marks, you need to press space after. So, Ã³ is Â´+o, Ã is Â´+i. Here are the Icelandic vowels with accent-like diacritical marks ÃÃ¡ ÃÃ© ÃÃ ÃÃ³ ÃÃº ÃÃ½. Copy-paste to a text file and use, if your keyboard does not support just typing them.

@Klutsi
I appologize. I just spent many many hours the last week to produce a good show and i am a total failure when it comes to tipping, grammar and many other things. I am using an english keyboard even though my native language is german.
But i am so glad JÃ³n FrÃmann, (i now used copy paste) sent this ash. It was really so very interesting. I expected results with many holes in it. If you do a google images search for SEM volcanic ash, you get to see pics from ( for example) hawaiian ash. But Eyja ash looks nothing like that. I did check in other microscopes too. And i would say 50 % is volcanic glass. But there were really complete crazy things to be seen. And i have no clue what this could possibly be.
Look at this
http://www.flickr.com/photos/arselectronica/4656313200/in/set-721576241…
I found that in a sample sent by Christian, i found nothing which looks only remotedly alike since the first viewing.
I asked the vistors of my museum what they think that looks like, they said toothpaste.
I would really like to know what this stuff really is.

@Birgit - Heh. After you set up the gallery, I went through the pictures - and I copied that one into my files. It really is a strange one. If it were larger, I'd say, "man made", but it is so small. It looks, indeed, like tooth paste or a candy bar; something extruded from a machine.

When I saw all the holes in the ash, I thought, "no wonder it blew apart!"; those holes must have been bubbles of high-pressure gas - and wonder of wonders: those holes were filled with even tinier particles. Clearly, very unhealthy stuff to get into your lungs.

@Klutsi
Yeah and what is very astonishing for me Colour does not normally display in SEM images. But sometimes there is this white stuff, i can grab. And in the samples of ash which were sent which had been touched by water, you find little to none. So the white stuff is obviously vanishing in water. I find that fact rather interesting

@Birgit Austria ...resident geologist says he thinks the extruded-looking stuff is isometric magnetite crystal ( a skeletal crystal.)

@10 Birgit Austria ...resident geologist says he thinks the extruded-looking stuff is " isometric magnetite ( a skeletal crystal.) " Anyone else?

@8 Stigger. Thanks for the post of the eyewitness account. I'm looking forward to reading the account.

@10 Birgit Austria-- wow. That is a strange mineral. Amazing the little airholes in the other stuff. Thanks for your generousity in posting.

@11 Kultsi-- There's an accent key on your keyboard? No wonder it's so hard for 'mericans to do accents-- I've got to press like 3-5 keys at a time to get the accents. It's easier to just hope to be forgiven. ;-)

@Birgit, parclair, etc.

Indeed, I have accent keys on my keyboard - and the Finnish language has absolutely no use for them. Using foreign words and languages is common, though, so I think that's why.

I did a bit of digging into keyboard layouts at http://en.wikipedia.org/wiki/Keyboard_layout and it turns out the US standard keyboard is severely limited in functionality. Changing it to use the US International layout greatly helps, the only real drawback being the apostrophe key becoming a nul key that produces acute accent with vowels and only producing an apostrophe when followed by a space or a letter not meant for acute accent.

Changing the active keyboard layout on the fly is a very simple thing in Windows; I currently have three.

The latest Finnish layout - which I don't use, yet - seems to be very versatile, being able to produce all the Nordic characters.

The second EQ in 2 days in the region:
5.3 2010/06/11 02:25:13 17.755 119.475 4.4 PHILIPPINE ISLANDS REGION

@Birgit Keyboards apart, your job an JÃ³n FrÃman's make us all proud to be here. It's a great honor to share this space with such brilliant and nice people. Vielen Danke!!!!!
BTW For those with available time I strongly suggest to read throughout this blog's earlier archives. Like Erik said, you'll be surprised with the many interesting discussions not only about volcanoes but a little bit of every exciting theme "extruded" from volcanoes, geology and all.

"Floating cities" again on Turrialba cam. No doubt now: there's lava coming from the vent.
http://www.ovsicori.una.ac.cr/videoturri.html

Renato, if you look at the 'Maps' section under each USGS EQ report page, you'll see an entry for 'Historic Seismicity'

It is a GOOD THING to check out the map for 1990-present and 2010-present, for frequency perspective wrt magnitude and location to seismically zones, with features such as ridges, faults and rifts.

@Passerby #20 Thank you. I've just checked at PHIVOLCS and looks like these magnitude EQs are not uncommon around the archipelago. Scary, though, isn't it? We get a 5,0 Mg once in a blue moon in our country.
I was also checking on volcanic activity from Guatemala and Ecuador:
Alert level raised to orange for high risk zones on Tungurahua:
http://www.hoy.com.ec/noticias-ecuador/declaran-alerta-naranja-en-zonas…
And lava flows continue on Pacaya. "This activity still poses threat to the inhabited areas" , said in a statement the State National Coordinator for Disaster Reduction (Conrad).
http://www.lahora.com.gt

But USGS maps are definitely more detailed. Amazing!

@jbcedar{at}yahoo.com [1]

Well, according to some accounts the snowpack in Washington State is at about 112% of normal. I'd like to see the positional info on those sub 1.0 quakes they were talking about. That would be a nice plot. :)

@Lurking Just an amateur observation here: have you noticed the circular pattern formed by recent earthquakes on the USGS real time seismic map for the US? Starting from California extending to Sth Nevada, then Utah, than a gap, than Yellowstone, Idaho, Wyoming and Montana border, than to the West towards Oregon /Washington Border and then following the coast towards southern Oregon and back to California. You're the guy who can "see" those things and put them in 3d.

Meanwhile, sky is clear over EyjafjallajÃ¶kull. No eruption!

Hmmm... and all I had to do was look.

www.ess.washington.edu/SEIS/PNSN/RAINIER/rainrec_eqs.html

It appears that they already lay the data out in time vs depth series plots, to no need to fiddle with it and try to make one myself...

While I don't see any "stacked" quakes in the last month or so at Ranier, you do have to wonder about the 3km deep quakes being snowpack.

Bah... their plots aren't close enough in time to see where they are at... Here is my rendition of the most recent ones.

http://i48.tinypic.com/2vtxg87.png

Depth verses time, color denotes magnitude.

Data source: www.ess.washington.edu/SEIS/PNSN/RAINIER/rainrec_eqs.html

For a lat-lon representation the one they have there is nice.

@Renato I Silveira

Yes, I have noticed. While I may be wrong, the best way to visualize it is as follows, imagine a carpet being pushed up against a wall.

http://i46.tinypic.com/mcglmt.jpg

Once it hits the wall, it stops sliding. If you had a really sensitive microphone sitting at the carpet/wall meeting point, you would hear the little squeaks of the carpet fiber rubbing on the wall. If you keep pushing the carpet will develop a bow in it as the extra material has no where to go but up.

http://i45.tinypic.com/2cqjqrp.jpg

Again, if you had that really sensitive microphone at the bending area, you could hear the fibers rubbing against each other.

This is a rough idea of what is going on in North America. The Pacific plate is the wall, and the back bone of the mountain ranges are the bump in the carpet.

There are other forces at work, but that is the gist of why there seems to be a line of activity roughly on a North south line at that region, back from the coast.

Just today there were two quakes at the Wasatch Front in Utah. More carpet bending.

Hope that helps.

Of course, it helps! Love your outstanding graphs. We need, you, Lurking! Thanks!

Nah, ya don't need me, all I do is graph stuff and read. Speaking of such, here is a small collection of those "other forces at work" that I mentioned. Each one of these structures impart some sort of weakness to the crust and tend to have a few quakes from time to time. Most notable are the quakes near Oklahoma City. They tend to be in the area of the southern extent of the Nemaha ridge, I know of one quake that occurred at the north end, but most of the discussion I ran across tried to attribute it to a UFO or a meteor. Funny how it was at the North end of that purple line.

Not shown but deserving mention... the Horst and Graben of the Basin and Range, Death Valley etc.. The odd lineament in Washington/Oregon, the Central Kansas Uplift, The Mississippi Embayment... the list goes on. All coupled with the carpet thing.

http://i47.tinypic.com/34qsj08.png

Something interesting to note. See the north east end of the line of the Snake River calderas? That's Yellowstone. Notice how the quakes are North, South, and sometimes in front of it (off to the North East) Another idea is that these quakes may represent a "wake" as the hotspot/plume tail moves off to the Northeast. As it moves along (actually the plate moves) the area moving over top of it heats up and expands (making quakes). As the crust moves off of it it cools and contracts (making quakes).

I thought that I would at least mention it. Dollars to donuts says it one or both of those ideas in play.

EyjafjallajÃ¶kull is huffing and puffing steam this morning. The wind up there is quite brisk, so the steam gets swished away without rising much.

Looks like things are winding down - a lull, at least: few quakes, very little tremor (except from wind etc, 20 m/s yesterday) and emissions look like plain steam, which is going to go on for some time: there is water in abundance and quite a pile of hot rocks. There might be gasses, but they cannot be seen.

You guys all rock! What a great series of entries.

Birgit that's fantastic stuff! I hope Erik picks up on this and gives us another lesson in interpreting the structure of the ash. The cross section of that strange one looks like a piece from a jigsaw puzzle which is very fitting given how much we all tried to figure out all the pieces. Maybe Eyja is just giving us a sign. (btw Kultsi hat Recht mit den Tasten
Ã³ Ã² (hey that looks cool!)
... oben links zwischen der Ã und LÃ¶schen-Tasten)

Carl, you are right on Taal. High population, constrained geography, lots of water, southwesten monsoon going on. History of just about every risk in the book (tsunami, pf, ash, calderas etc. etc), flimsy housing in Manila's slums, very eruptive history. Let's hope we only have to witness a mini Taal event. I've certainly got my fingers crossed that it doesn't come to much as the volcano could be a real killer.

Renato, what do you mean by "floating" cities... do you mean that heat is distorting the light from the city in the background? Otherwise the cam doesn't look very different to me at all. Ã³Ã²

Hello to all,

New update on the I.M.O.website. Eyja obviously very quiet now.3 new quakes though under Katla..

Adrian, check out this before you get too excited about quake activity under katla:

http://islande2010.mbnet.fr/2010/03/eyjafjallajokull-levolution-des-der…

PS welcome to the club by the way!! (This place is very addictive)

PPS don't forget to press the play buttons on those links!!

Crater Lake Resort

The resort offers a unique twist to the usual island experience. It is home to many species of birds and fish including the rare maliputo, which is a kind of fresh water mackerel that can be found in the waters around volcano island.

The resort pavilion is the perfect place to hold gatherings for up to about 100 people. It has a wide floor area that is ideal for family gatherings, team-building workshops, or special celebrations. Here, you can enjoy the cool breeze of the fresh island air while spending time with friends and family.

http://www.taalvolcano.net/

Fresh steamed mackerel. Yummy!

@33 34 35.

Hi Bruce,

Umm,I think it will take a few more than 3 quakes to get me excited. I just happened to mention them in passing,as it were.
I have seen the timelapse sequences before but not for sometime and yes, it does put things into context.
P.S.Thanks for the welcome but I have been around for some time.

@ Adrian, pardon sire! Didn't mean to do you a disservice.

Raving @myself (#36)

Have a look at the picture album. It is an amazing place.

http://www.taalvolcano.net/pics/index.html

@38 Bruce ! No probs my friend. I do more lurking here than Lurking himself...
@36&39 Raving,yes it is a beautiful place. I just hope that the only poor creatures that get steamed are the Mackerel.

@ Passerby

If you haven't been, and you get a chance, go to Hellisheidi - it's an awesome sight and unlike any industrial building I've ever been to before. It's as if someone had commissioned Apple to design a power station - all glass, bleached wood and shiny metal.

The staff are very friendly and you get to see a lot of what's going on behind the scenes.

@passerby/Mike: Hellisheidi also has a nice visitor center.

@Lurking @birdseye I was on the other thread, have to go now. I'll post my comments later. Thank you!

@41, 42. Have seen reports that the Hellisheidi plant is a top tourist destination.

@29: your plot follows the regional temperature and precip trends for April-May. No surprises in you 2vtxg87 plot.

I posted a couple of comments in threads in Mar-April here noting elliptical continental, shallow-EQ patterns for Eurasia and the US. In Eurasia, its a tectonically active plate collision zone with bolides (chips of primitive crust) reported caught in the squeeze.

In the US, the mostly shallow, frequent quake pattern occurs on faults, but the larger pattern appears to match enhanced winter/spring precip. caused very low riding jet stream carrying ENSO wet weather across the lower 48 and then rising sharply northward along the Atlantic coast.

So I agree with Lurking's comment on layers of mechanisms at play in the Big Picture pattern of EQs. For Ranier, it's tacitly snowquake activity associated with sharp warming trend and clearing skies in late April after a cool and wet (at least for the northern Cascades) winter. With the drop in ENSO signals, we had a return of wet, cloudy and cooler-than-average temps.

Photo of sulfurous gas emissions at Taal, posted today on the BBC News website, under 'Day in Pictures' section.

http://news.bbcimg.co.uk/media/images/48050000/jpg/_48050926_009501635-…

Hey guys, just an update on Katla...there are three new earthquakes, making a total of 6 recent ones there...

could this mean anything?

@bowslice (#46) - Yes, anything.

On a serious note I think we should wait until those quakes get definitely located; now the quality numbers are so-so.

If we get 30 or so at that location within the next 48 ours, I'd start getting concerned - and I don't think I'd be the only one.

@ 46 - All the Katla quakes are very shallow (less than 1.5 km) so my guess is they are related to the ice and/or caldera structure, not magma.

@bowslice (#46) - Yes, anything.

On a serious note I think we should wait until those quakes get definitely located; now the quality numbers are so-so.

If we get 30 or so at that location within the next 48 ours, I'd start getting concerned - and I don't think I'd be the only one.

Uh-stigger. Just read the thing from cover to cover and all I can say is that there are some 25 million within 50 kms and a helluva lot of that is within the ten kms your priest elucidated on. Those same towns are still there and there will be ZERO chances of evacuation if it should suddenly go.

My bet is that if it suddenly got jiggy, we would see literally casualties in the millions.

#50 M. Randolph Kruger - population numbers have increased substantially since he wrote his account and yes, I agree they would have ZERO chance of evacuation.

A cat may forego a situation but can think virtually a chicane

What a great story, and not just for the success of the team. The way they all work and volunteer together is wonderful, and teaches more about life than many of their classes.

For the record I've seen your page or blog before and I'm sorry I didn't add it as a bookmark before because organized and it's well constructed. If possible can you take a look at my blog sometime or email me back with help or suggestions as to what I could improve on my blog site. Thanks.

I enjoy to play games, but I particularly like to play Big Game Hunter. Desire to find some Big Game Hunter Cheats? Just press my link. - Thank you for your email. This Internet of yours is a wonderful invention. (email to Al Gore, mocking his famous Internet invention claim, quoted in Newsweek, Mar 2000) Attributed to George W. Bush

Interesting article. Well done, i hope to read more like this

thomas, i think you are absolutely right in your comment, i agree with you 100 percent

Alert level goes up at Taal in the Philippines

eklemetti — Tue, 08 Jun 2010 16:54:30 +0000

Alert level goes up at Taal in the Philippines

The steaming vent area at Taal in the Philippines in September 1965, when the volcano produced a VEI 4 eruption.

The Philippine Institute of Volcanology and Seismology (PHIVOLCS) has raised the alert status at Taal to Level 2 (of 4) and officials in the Philippines are getting ready if the volcano does come back to life for the first time since 1977. Taal is a mere 48 km (30 miles) from Manila - the capital of the Philippines and home to over 21,000,000 people in the metro area of the city. This location made Taal one of the UN/IAVCEI Decade Volcanoes as a large eruption from the volcano could be devastating.

The volcano has been quiet for almost 33 years now, but last year Taal began to show signs of life including increased steam emissions and bubbles (indicating degassing) in the volcano's crater lakes. Today, however, PHIVOLCS is reporting over 30 high frequency seismic events underneath the volcano and a greater increase in steam emissions, prompting the elevation of the Alert Status from 1 to 2. Now, earthquake swarms have occurred before at Taal over the last decade, and there have even been muddy geysers that have popped up in the crater lakes - these geysers prompted the last Level 2 alert in 2006 (thanks to deformation and increased seismicity that came with the geyser activity). Many of the eruptions over the last 40 years have been VEI 1-2 explosive events that were strongly influenced by the presence of the crater lakes (phreatic or phreatomagmatic eruptions), as the 1976-77 eruption produced copious ash-and-steam clouds. However, in 1965-6, Taal had a series of VEI 3-4 eruptions that killed at least 200 people. This eruption produced a 15-20 km ash plume after starting as basaltic spatter (sound familiar?). Additionally, a 1911 eruption produced a tsunami and killed almost 2,000 people.

You'd think with a volcano with as much of a deadly history as Taal that people would avoid it, however, Taal is actually a popular tourist destination thanks to its proximity to Manila. Volcano Island, in the middle of the largest crater lake, is now off limits due to its constant degassing, but much of the rest of the area can be visited. This tourism, combined with the high population within 100 km of the volcano means that PHIVOLCS will have its hands full if the volcano shows signs that it might have a significant eruption. PHIVOLCS does have hazard maps for Taal showing the zones of highest danger for ballistics, base surges (pyroclastic flows - the #1 hazard according to PHIVOLCS) and lakewater escape (due to seismicity) but one would imagine that ash would be a major problem if the volcano erupts explosively. Luckily, the volcano is closely monitored for seismic changes, lake temperature and chemistry and deformation from the Taal Volcano Observatory. For those intrepid webcam watchers, there are a few Taal webcams out there to check out.

eklemetti Tue, 06/08/2010 - 12:54

Tags

Hopes that United Nations funding might be available for Decade Volcano projects did not come to fruition,

http://en.wikipedia.org/wiki/Decade_Volcanoes#Aims_of_the_program

Bad volcanic site distribution for pork barreling, globalist politics.

Erik-- I answered my own question in the previous link-- thanks, and sorry to bug you.

Info: only the 1st link on the webcam page is of the volcano; I'm still looking for more. Not that I'm addicted, or anything ;-P

Center for Sustainable Destinations.

http://travel.nationalgeographic.com/travel/sustainable/about_geotouris…

There will be big growth, big money and big development in "sustainable" geotourism. I can see all those naturists chasing after erupting volcanoes now! Zoom zoom zoom. ...

Hahahah.

When I see the lack of seismological monitoring resources in Africa, Vanuatu, S. & C. America and elsewhere, I get annoyed and frustrated.

The reasons are the obvious ones. Limited funds, local responsibility, unknown shortfall, more immediate necessities, a shortage of volcanologists, NIMBY... "Who cares if a volcano should blow up in some far off place killing people who foolishly live there and were unfortunate in not securing an advance warning system."

Here are two profitable reasons to monitor and research volcanoes in far flung corners of the world.

1) There is big money in geotourism.

More significantly tourists who travel to remote destinations are apt to spend time and money at other regional attractions.

Getting the publicity to pull in the geotourist is crucial. Internet access to real time monitoring is a big suspenseful tease.

If the pass-through economic benefit to other regional states had been emphasized, the "decade" project might have gained support for UN funding.

2) There ought to be huge interdisciplinary spin-off benefits from volcanological research. The topic of interest is a complex, heterogeneous, multiphase system that provides prodigious data from a diverse set of examples.

I expect that volcanology is an ideal accessible real environment to develop expertise in very complex, multi-component dynamic interactions.

The insights and experience gained from volcanology stand a good chance of being suitable for other situations else where.

Hey! What's that to the left of the image on MÃºlakot cam? Looks like steam or PC flow coming downslope??? Also seen from the extreme left of HvÃ³lsvÃ¶llur, I think.

There's a cloud of steam moving fast to the left of the crater on HvosvÃ¶llur! Winds are very low.

Well, that could be a cloud or another dust devil, but the speed of the wind, according to JÃ³n's helicorders is null at the time, and the cloud moved so rapidly... Now it's gone. But the steam area on MÃºlakot is still visible.

@ Raving no.3 Geotourism Plans

So: "big growth, big money and big development", eh?!

Sure thing, if you are right and we get all those "naturists (!) chasing after erupting volcanoes". (But of course, they will have nowhere to KEEP their money! Sorry!)

Your vision for geotourism would be a "hot project" indeed.......

;-)

Hi all, I'm an interested bystander, not knowing much at all about volcanos, but as a scientist the discussions on this website make for a great read everyday.

Just thought I'd say, I visited the Philippines in 2001 and on my trip around the islands I visited lake taal including a boat trip over to the central "volcano island". If anyone is interested I could dig out my old photos of the trip. I remember lots of interesting coloured water / crystals on the edge of the (central island) crater lake with some venting gases & a very hot day!

It would be a disaster if there was a large eruption there, as there are many houses surrounding the lake, and most people wouldn't have the resources to do much to help themselves if anything happened. A beautiful part of the country, nonetheless.

@ 9 Ems, Please do upload your photographs,they'd be interesting to look at.I was watching a video on Youtube in which tourists from Manilla were walking around inside the crater just before it was made off limits. I wondered if they realised just where they were walking lol.

Hi Zander, I will try & dig them out - think they were not digital photos so I'll see!
Although it's a while ago, there certainly weren't any indications to make tourists aware that it was in anyway an active volcano, other than what you could see/smell. I think that until you see images from google earth do you realise that the larger lake taal is the actual entire volcano - not just the little tiny volcano island in the middle of the serene lake!

It is (and has to be for many) about the money that can be made from tourism, as incomes are so low out there. I doubt whether any of the governments contigencies will have been communicated to the public in these areas:
http://www.mb.com.ph/articles/261295/gov-t-assures-readiness-case-taal-…

There seems to be some ambiguity as to what classifies as Taal volcano.Some websites say Taal is the world's smallest volcano citing the 408 metre tall cinder cone at one corner of the island inside Taal lake. Surely the volcano is the entire island inside Taal lake with the cinder cone being one of a couple of vents?

@ 12. Im pretty sure the lake covers the remains of a caldera collapse, I recall reading that Taal had VEI 6 eruption a few thousand years ago. Im pretty sure the volcano is the whole lake including volcano island.

Good question, what indeed is a "volcano"? Is it the mountain, the vent(-s) or the magma chamber/piping? Since the former are manifestations of the latter, I'd say the latter is the volcano proper. ;)

@14, Simon, I think you're right. See the physical features description in the link:

http://volcano.phivolcs.dost.gov.ph/update_VMEPD/Volcano/VolcanoList/ta…

I agree with Henrik. It seems a bit ridiculous naming one little vent in a rather large caldera complex the smallest volcano in the world.

Wikipedia:
"Taal Lake lies within a 25â30 km caldera formed by four explosive eruptions between 500,000 and 100,000 years ago. Each of these eruptions created extensive ignimbrite deposits, reaching as far away as where Manila stands today."

That's small?

@Erik - I agree with Renato. I'd hunt him down, though, and hang him by the unmentionables he/she/it keeps mentioning.

@13, Zander, sorry, posted after two sips coffee. Yikes. 2 days in a row.

@ #12-#16 I think we all agree that the Volcano Island of Taal is not tall. Somehow that reminded me of a saying by Robert A. Heinlein, "Never frighten a small guy. He'll kill you." (From RAH "Notebooks of Lazarus Long", in "Time Enough for Love")

Kutsi#19 - RAH now there's a name that takes me back to my teenage years... Auctioned off a large pile of SF to a local group a long time ago, and I've missed them ever since. I had a girlfriend who used to enigmatically quote RAH "sayings" at me, and I had to go and reread the books to find out what she meant.

@Gordon - I gotta boast here: I have "RAH Grumbles from the Grave" signed by Ginny.

I grok what you're saying---)

@ Parclair, have another go lol.

@23 Zander. I hoped if I just didn't say anything, no one would notice. Sorry Simon. *eyeroll* *Headslap*

Hi to All,

Todays "silly quiz". Has anyone spotted that the Flir cam has had the same image up for about 24 hours now ? lol.

But on a more serious note..

There appears to be a new outbreak of meltwater but quite a way to the right of the old lake. I have a 81cm monitor on my computer and even with the poor definition on the Thoro Cam (set on 400%), I cam just make out what look to be 4 plumes behind the new meltwater just in front of Eyja herself. Am I seeing things or does anyone else see what I am seeing ???

Sorry,"cam" should be "can".

Henrik 14: Very good question. When it comes down to it, precisely defining "volcano" is dam' difficult.

-Is it the vent itself?

-Is it the vent+ accumulated materials ejected from it? (The 'volcanic edifice') This is the popular non-scientific definition

-Or is it the entire plumbing system, going down 100km and possibly underlying several hundred sq,km, which includes the edifice as a (fairly small) part of the whole? ('the volcanic system')

Logically it should be the latter, but that raises problems eg with several closely-spaced volcanic structures. Are they related, and part of the same system? Many volcanoes were named (because they're pretty obvious features) and classed as independent centres long before the days of petrographic study and trace-element analysis. and there is possibly a certain caution about re-classifying them.

Are the Three Sisters separate volcanoes, or progressively younger manifestations of the same system? If the former, why is/are Mexico's 'Three Virgins' classed as one volcano? And so on.

And what about an active cone within a broad caldera? Is Taal defined as Volcano Island, or the whole of the caldera filled by Lake Taal? If the latter, should not Sakurajima be defined formally as including the whole Aira caldera? (to give one example) It gets very confusing.

Kutsi#21, I am jealous, not so much of the signed copy, but that you still have them. I just checked my attic and only "time Enough For Love" remains which I just couldn't get rid of..

I just had a quick look to see if there were any appropriate aphorisms for "Eruptions" and bizarrely on the second page I looked (pg368) I found the following...

"Beware of the "Black Swan" fallacy.Deductive logic is tautological; there is no way to get a new truth out of it, and it manipulates false statements as readily as true ones.
If you fail to remember this, it can trip you - with perfect logic. The designers of the earliest computerscalled this the "GIGO Law" i.e, "Garbage in Garbage Out".
Inductive Logic is much more difficult - but can produce new truths."

Has anyone noticed that the wildflowers have flowered on Mula cam 1?

While searching for information on Italian seamounts today, I came across an interesting little theory on the myth of scylla-and-charybdis.

http://virtualwayfarer.com/a-possible-origin-for-the-scylla-and-charybd…

The author didn't carry the seamount notion as far as I might have, to include a seamount-fissure system that might have caused a temporary whirlpool to develop nearby, perhaps formed by hot gases ejection into anticyclonic flows known to exist in the waters above active shallow seamounts.

There is a seamount found within the Sicilian Straits, The Malta Seamount, but the model could have been any the of many seamounts found in the Mediterranean.

Henrik 14/Don:

Very good question. When it comes down to it, precisely defining "volcano" is dam' difficult.

-Is it the vent itself?

-Is it the vent+ accumulated materials ejected from it? (The 'volcanic edifice') This is the popular non-scientific definition

-Or is it the entire plumbing system, going down 100km and possibly underlying several hundred sq,km, which includes the edifice as a (fairly small) part of the whole? ('the volcanic system')

Are the Three Sisters separate volcanoes, or progressively younger manifestations of the same system? If the former, why is/are Mexico's 'Three Virgins' classed as one volcano? And so on.

How about the volcanoes of Iceland..

the whole island there is actually one big volcano,that has lots of vents and cones and mountains of former active and active "volcanoes"...

to just name a volcano is not always as easy to define, as with the "Taal" volcano wich is a newly formed crater, formed in the old caldera,(the lake)wich is actually a part of a larger volcanic system that made that island..

so the whole island should actually have the name of the Volcano right??

Taal Island??..

Thor: I dug out my copy of 'Volcanoes Of The World' (1994 edition) and found this on Iceland (p152)

"Since our 1981 book, reorganisation by volcanic systems...has resulted in a substantial drop in number of volcanoes (from 71 to 35) but more meaningful grouping of genetically related surface features"

Seems to be relevant

#19, 20 and 21: still have all my Heinlein (non signed) but precious nonetheless. My only signed book is Gaia by James Lovelock, given to me by an ex student who met him on a uni field trip and asked him to sign it for me. It is my most treasured thing.

@Gordon #29 Yes, I've seen the wild flowers! Someone had mentioned before and I went there to check... Like in the Phoenix myth, from the ashes they bloom!
@Passerby #30 Talking about myths... I love the way the ancients found to explain what in many cases remain unexplainable still today . The Scylla-and-charybdis was one of the myths that inspired me most awe when I was a youngster reading the Odyssey - just couldn't figure out what they were exactly - giant whirlpools with a big open mouth? I'm not convinced that lava bombs could "explain" multi-headed monsters. What I think is that they didn't actually want to "explain" anything: they accepted nature the way it is and described what they experienced in a poetic form. And may be they were closer to truth doing so. (?!)
As for volcanoes, I keep the image I've always had from them - the good old conical shape. In fact, until Eyjaf, I didn't care much about Icelandic volcanoes because they didn't match the shape I had in mind since my childhood. Now that I fell in love to them, I have to accept the idea of them being effusive cracks on Earth's crust. What about calderas? Well, they are big volcanoes, with a crater lake and a small volcano within. Can anyone be more scientific than that? :)

Another EQ on Jan Mayen micro-plate:
4.9 2010/06/09 16:54:24 70.351 -15.165 10.0 JAN MAYEN ISLAND REGION (USGS)

Flooding alert on EyjafjallajÃ¶kull (lahars?), heavy rains forecasted between 5 and 9 in the morning - I'll post it in Icelandic, maybe someone could translate it:

Mikilli Ãºrkomu spÃ¡Ã° og hÃ¦tta Ã¡ aurflÃ³Ã°um - skrÃ¡Ã° 09.06.2010 kl. 17:10
Ã nÃ³tt er spÃ¡Ã° allt aÃ° 40 mm Ãºrkomu Ã¡ EyjafjallajÃ¶kli. ReiknaÃ° er meÃ° aÃ° mest rigni Ã¡ tÃmabilinu milli kl. 5 og 9 Ã fyrramÃ¡liÃ°. ViÃ° Ã¾essar aÃ°stÃ¦Ã°ur er hÃ¦tta Ã¡ aÃ° Ã¶skulÃ¶g Ã¡ EyjafjallajÃ¶kli geti skriÃ°iÃ° fram og niÃ°ur farvegi Ã¡a sem renna suÃ°ur af fjÃ¶llunum. Ãetta Ã¡ helst viÃ° SvaÃ°bÃ¦lisÃ¡, LaugaÃ¡ og KaldaklifsÃ¡ en einnig geta slÃk flÃ³Ã° komiÃ° niÃ°ur HoltsÃ¡, MiÃ°skÃ¡laÃ¡ og ÃrÃ¡.

@Renato, #40: In short: They expect heavy rainfalls this night - up to 40mm of rain between 5 and 9 in the morning. This may lead to mudflows from the EyjafjallajÃ¶kull in the area.

#37 @Chris,Reykjavik Thank you! Hope you stay away from the path.

Mud flows are much bigger killers than lava flows! So please, attention!
A 6,0 M EQ in Vanuatu.
6.0 2010/06/09 23:23:19 -18.586 169.471 17.8 km VANUATU (NE of Traitor's Head)
According to Smithsonian Institute: "A submarine vent offshore between the tip of the peninsula and Goat Island, 5 km to the NE, erupted in 1881, the only historical activity of the Erromango volcanoes".

Re: Eyja, A little bit gleaned from the IMO page dated May 24 (under 'ashfall") -"...Volcanologists and Geologists term this quieter spell of volcanic activity as a âpausedâ phase. However, it is typical for a volcano like this to have several âpausesâ as part of its overall eruption phase. Only when the volcano has been âpausedâ for three months will it then be regarded as being dormant."

Does it mean something?
5.0 2010/06/10 02:13:23 7.256 126.840 60.8 MINDANAO, PHILIPPINES

6.0 EQ Vanuato 6 minutes ago

All, for interest, as promised yesterday (#9) I dug out my old taal photos. As I suspected they were poor quality old-school photos, so I scanned them in and the results can be seen here:
http://picasaweb.google.co.uk/107090910741035698162/Taal?authkey=Gv1sRg…

they at least provide an overview of the whole structure of taal lake and it's size. Volcano island is to the right in photo 1 - behind the blade of grass! & in the centre of photo 5. Photo 3 provides a view from the side of volcano island in low evening light. Photo 4 is the panorama from within volcano island itself. Hope they are of some use!

Hi Ems@43, I think everyone is over on the new page now - thanks for the photos, I'll put a reference over there for you.

Some info. on Taal vocano = about 5000 people live on volcano island, mostly involved in fishing and farming, and tourist guide's, Nobody should be living there of course but this is the Philippines!!. I have lived in Tagaytay for 3 years, we are 2000-2500 above the lake so the weather is cooler. The big fear is steam explosions in the lake which is 30 miles long.

From the Library of Congress: the original report on the 1911 eruption of Taal by Reverend Miguel Sanderro Maso of the Weather Bureau. It's a big file but fantastic read.
http://ia340935.us.archive.org/1/items/eruptionoftaalvo00philrich/erupt…

A boy can lose to hide from rubbish but can motion a blacksmith

Hey I have been following your articles quite a lot & I must say that you come across as a pro in your area of study. You should start blogging more often , it would be really great.

Monday Musings: Kilauea, Pacaya, EyjafjallajÃ¶kull and more!

eklemetti — Mon, 07 Jun 2010 01:48:53 +0000

Monday Musings: Kilauea, Pacaya, EyjafjallajÃ¶kull and more!

Looking for some volcano news - you've found it.

A shot of volcano "tourists" near the erupting Pacaya. Photo by the Associated Press.

Eruptions reader Dr. Boris Behncke dropped a note that Kilauea has not one but two active lava lakes right now. The lava lakes can be seen on the webcams for the Halema`uma`u Crater and the Pu`u O`o flank vent. The latest status update from June 6th by the USGS Hawaiian Volcano Observatory talks about both the summit and rift activity (video) on Kilauea as well. Meanwhile, Hawaii 24/7 has a piece in the Volcano Watch series about whether residents of Maui need to be concerned about lava flows.
Some stunning - both for the volcanology and the questionable judgement of gawkers - shots from Pacaya in Guatemala. People were getting right up and cozy with the erupting volcano - but you can check out shots of the latest lava flows from the volcano from the safety of your home.
And if you want to hear about working on an active volcano - but not in a glamorous Pierce Brosnan sort of way - check out this story on sulfur miners at Kajah Iwen in Indonesia. Needless to say, the volcanic gases being emitted from the fumaroles are full of toxic chemicals like hydrogen sulfide, sulfuric acid, hydrogen fluoride and more - but sulfur is an valuable industrial commodity, so someone has to mine it, usually by hand. At Kajah Iwen, 14 tonnes of sulfur are mined daily - and the men carrying the sulfur make $66 a day carrying ~133 kilo of sulfur down from the fuming summit.
EyjafjallajÃ¶kull continues to rumble - either showing signs it might be headed for new activity or giving us a last gasp. The volcano continues to feel tremors and is producing a 4.5-6 km (15-20,000 foot) steam plume (icelandic) with some small explosions. The latest Icelandic Met Office status update (sadly, the IMO seems to only be updating the icelandic version) mentions material in the crater causing the explosions - likely hot vent material interacting with water creating phreatic explosions. Meanwhile, Easyjet and Airbus will be testing its new ash-avoidance system. The system uses infrared to detect ash up to 60 km away and at altitudes between 1.5-15 km (5,000 and 50,000 feet). I don't know if I'd call the Airborne Volcanic Object Identifier and Detector (aka AVOID) a "silver bullet" like the article claims (video), but anything to make aircraft safer from ash would be an improvement.
Lastly, I was sent this Arizona Republic article on Robert "R.B." Trombley and the International Volcano Research Centre. I don't have much comment on this beyond the dangers of the internet, the mainstream media and how we perceives "experts" in this age.

eklemetti Sun, 06/06/2010 - 21:48

Tags

volcanoes and the economy

volcanoes in the media

webcam

ash

aviation

Hawaii Volcano Observatory

volcanoes and the economy

volcanoes in the media

Thanks for the Kawah Ijen - Link. I was there one and a half year ago. Absolutely impressive. But it is a hard trip on bad roads even with four while drive, until you reach the Ijen Plateau. BTW: There is also a volcano called Merapi there, but it is not the active and dangerous one close to Yogyakarta (some news mix this up on maps), it is the 2799 high point of the Ijen complex.

Erik: I always have to take photos like those on Pacaya with a pinch of salt, since the foreshortening effect of telephoto lenses can sometimes make people seem far closer to the danger zone than they actually are. On the Trombley story: what's the betting his information sources include this blog, the Volcanism Blog, and John Seach's site?

Thomas: 'Merapi' I think, means 'fire' or 'fiery red' in Indonesian; which suggests to me that it has erupted since human settlement of the area (although not historically active). Life expectancy of the 'miners' -quarrymen, perhaps more accurate- must be appallingly short, given the working conditions

Thanks for posting the link about Trombley. We have to be aware of the amount of information circulating on the internet that lack any scientific basis. On previous threads we have already been alerted about misleading links that we have unawarely posted, eager to provide useful information for us volcanophiles. Keep us updated on this, please.

Erik,
The Kajah Iwen mine is impressive, but it is negligible in the scheme of world sulfur production. Most sulfur is not mined by hand. It is generally an industrial byproduct, e.g. from sulphide ore smelting.

@Lab, #4: A lot of sulphur comes from the raffineries of the oil industry.

Hi to all,

Is that a steam plume coming from the lake on the Thoro cam ??

I swear that there was some type of plume coming from the right "bank" in front of the lake, but its dissapated now.Very strange.

@ Adrian, I saw it too. Looked like quite a big puff of steam lasted a few minutes then slowly disappeared. Maybe it was an escape of hot water coming off the glacier?

Have a look at mula cam, it's the first time I've seen any definition in the terrain on the mt. sides. there - but I think it's all blowing dust, might be what was seen on Thoro, too...or mist rising?

Hi Marginata, thanks for that, at least I am not seeing things ! Steam seems to be coming from melt-water now and other locations.This has happened before though.

According to news reports, there is a small eruption going on in EyjafjallajÃ¶kull at the moment. This eruptions are not big, and often drop down to nothing.

Hi Jon,

thanks for the updated information. I.M.O. do not seem to be putting their updates out in English,as i think someone has already commented on,and my Icelandic is very poor.

I see what you are looking at, and think that the location is wrong to be steam, although it does appear whiter than the dust/ash blowing along the valley floor. My view is that it is dust being blown up the lateral moraine outside wall, and mixing with dust/ ash being pulled from inside wall by vortex from wind blowing over top.

I totally concur with you there Gordon, a fresh mind and a fresh pair of eyes are a great help !

Good morning, afternoon, evening, night (MAEN) all.

bigbenber blog has some cool pictures of Tuguruhua blowing smoke rings:

http://bigbenber.over-blog.com/article-rond-de-fumee-et-explosions-stro…

The blog points to a site where one can see the pictures in larger format:

http bigbenber.over-blog.com/album-1581553.html

Good evening all!

Is it just me, or did something started with the 1.4M earthquake below Katla? After the quake the tremors increased a bit on the HVO, ESK & GOD stations but not on the HAU & MID stations. The largest increase is in the HVO station.
Also the Snaebyli station registered increase in tremors.
Note that the Snaebyli and HVO stations are on the other side of Katla from Eyja. During the Eyja eruption HAU & MID registered as much tremors or more than HVO, ESK & GOD.

If my logics are not out the window completely I would say that this is not related to EyjafjallajÃ¶kull as such, and that it instead is belonging to Katla.

Please note that I am not saying that Katla is about to erupt, but that it is perhaps showing some slight unrest and that unrest might be a sign of future likelyhood of a Katla eruption... Hedging here;) But if...

The US will gladly give away it's excess sulfur supply; the entire annual production yield is a byproduct of waste-stream desulfurization. The question of what to do with the excess is unique among industrial minerals natural abundance, whereby the majority are in rapid decline.

http://pubs.usgs.gov/of/2002/of02-298/

I should also have written that JÃ³ns eminent helicorder is also picking up the tremors from Katla starting roughly at the same time as HVO, ESK & GOD.

The tremors registered at HVO, ESK, GOD & Snaebyli is mainly in the slow 0.5 to 1 herz region, whereas Eyja seemed to rockÂ´nÂ´roll at the faster 2 - 4 herz.

@Carl, Please check the wind noise before you over estimate the tremor noise from the volcano. At the moment there nothing on my sensors but wind noise.

Given that my sensor is at distance of ~40 km. The tremor from EyjafjallajÃ¶kull also need to appear on Haukadalur (hau) IMO station before I start to see them on my station at the same time.

Mulakot webcam clearly shows deposited ash re-entrainment from convection winds in the valley. Has been an ongoing issue for visibility/environmental health for area residents.

Back to sulfur production.

USGS has an interesting read, in the 2007 annual report, of somewhat unusual global market and production conditions (under minerals yearbook) that year.

http://minerals.usgs.gov/minerals/pubs/commodity/sulfur/

According to that report, the US is the number one producer and one half of all produced sulfur is used as a fertilizer amendment, often in the form of ammonium sulfate; major nation consumers are China and India. The rest contributes to industrial chemical demand, sulfur being one of the most important industrial chemicals in use (production graphics simply tower over all other chemicals in comparison).

Here in the Columbia Basin, over-application of ammonium sulfate in the past may have contributed to the dissolution of a thick layer of caliche hardpan in the shallow subsurface, according to a astute soil scientist with whom I worked for several years. In fact, on sampling field trips, we got side-tracked more than a few times checking out erosion slopes and road cuts, or hand-auguring soil cores to test his hypothesis.

We think that it's changed the historic rate of subsurface percolation (from the start of large irrigation projects more than 50 yrs ago). The NRCS won't say much on this issue, unfortunately.

Hello JÃ³n!

Thank you for the correction, seem to have misplaced your helicorder there:)
Had a problem finding the wind direction in that region of Iceland. Now that I have checked on the enormous wind-direction tool at Hvolsvelli (the free-swinging building-crane...) I now know that it is blowing from WSW.
And from the camera pictures there seems to be wind also around the silent HAU and MID, effectively ruling out wind as a probable source of the tremors.

Katla EQ http://en.vedur.is/earthquakes-and-volcanism/earthquakes/myrdalsjokull/…

Date Time Latitude Longitude Depth Magnitude Quality Location
Monday
07.06.2010 12:55:03 63.629 -19.623 1.1 km 0.5 99.0 8.8 km SW of BÃ¡sar

small uptick in tremors again

Interesting with 3 quakes so close to Katlas eastern caldera rim. I would really like to see up-to-date GPS figures for Katla right now.
Three rather small quakes, a little bit of tremor. If I remember correctly Katla is one of those rather pesky volcanoes that doesn't do a lot before it goes into high gear.
It would have been so nice to see if there has been any surface movement the last few days, ie. if there has been new magma coming up. GPS me:)

Mulakot cam some-what clearer

Update on activity
Eruption in EyjafjallajÃ¶kull, Iceland
Assessment 7 June 2010 14:40

Some eruptive activity is still in the western side of the crater. Magma explosions occur off and on producing ash, which falls near the crater. This explosive activity is accompanied by an abrupt increase in tremor. White steam clouds have reached a height of 6 km following these explosions. We continue to monitor the volcano closely.

In the western part of the crater, a new crater has formed at the site of explosive activity. Tremor pulses late 6 June accompanied steam plumes from this new crater. The plumes and explosions are small. Caving in of lava in the conduit can be heard between explosions. Only a part of the new active crater has been seen due to the steam. The glacial ice at the top is advancing rapidly to the GÃgjÃ¶kull otulet glacier.

In the afternoon of 4 June an increase in seismic tremor was recorded at seismic stations around the volcano, but decreased again in the evening. Small pulses of tremor were recorded off and on during the night. At around 0900h on 5 June the tremor reached a maximum before decreasing again. An increase was recorded late 6 June for a short time and small pulses were recorded last night. The tremor has been predominantly at high frequencies. A few small, shallow earthquakes have been recorded beneath the top crater in the last few days.

Details in a status report issued collectively by the Icelandic Meteorological Office and the Institute of Earth Sciences today at 11:00. See also status report from 12:00 4 June.

A couple comments before heading off to see the Red Sox in Cleveland:

@4 - Yeah, I am biased towards thinking of mining sulfur rather than producing it as a byproduct probably because I did my PhD work on a volcano what was also a sulfur mine (Aucanquilcha).

@2 - I agree, telephotos can make lots of perspective go out the window, but dang, still impressive.

@ the Katla EQ folks - one thing to watch out for are specifically shallow earthquakes (2 of the 3 recorded in the past 24 hours are less than 2 km deep) along the caldera edges. Calderas have faults along the rims, so you might expect to find earthquakes along these ring faults periodically, especially with an icecap on top of the volcano. Although its not entirely the same, you can look at general caldera structure here: http://scienceblogs.com/eruptions/2010/02/the_structure_of_calderas.php. So, I'd be surprised if anything seismicity under Katla is magma-related right now.

Those dust devils on the Mulakot cam are quite something

Tourists and erupting volcanoes.
Here a nice picture from Etna:

http://www.swisseduc.ch/stromboli/etna/etna04/etna0611-en.html?id=9

Totally agree with Erik on the shallow caldera earthquake origin likely to be icecap stress related.

Mined sulfur is in the minority as global sulfur source.

Significant dust devil activity on the Mulakot webcam, with a very large one visible right now. Webcam refresh rate appears to have been reduced.

From the IMO/IES report quoted earlier,

>In the western part of the crater, a new crater has formed at the site of explosive activity.

A satellite image would be useful.

Looking at the thoro cam, the wind is really blowing. It must be painful to be outside today from the face-stinging of the clasts.

Erik...

I think you are to happy with the Red Sox:)

None of the quakes where really shallow and two where deep, the first was 1.1M at 3.8KM (the shallowest), the second was 0.9M at 11.6KM and the third was 1.4M at 9.9KM.
So, I would guess that at least the second and third are unrelated to caldera fracturing.

Thank you for the link, it was nice!

Can someone tell me what the white cracks are in the webcam from Halema'uma'u http://volcanoes.usgs.gov/hvo/cams/HMcam/

@35 Snotra viking. On that cam, you are looking at a lava lake with crusting. The white cracks are where the crust is broken up. Watch long enough and you will see the crusts fall back into the lake and new crusts form. It's fascinating to watch. :-)

(with apologies to our Danish friends)..

"Something is rotten in Denmark".

Airlines to be profitable this year, Iata says
http://news.bbc.co.uk/2/hi/business/10253051.stm

From the BBC news article posted today:

Airlines worldwide will make profits of $2.5bn (Â£1.7bn) in 2010, an industry body has said. The prediction marks a huge upturn from the last forecast of the International Air Transport Association (Iata). In March, the airline association had predicted global losses for airline businesses of $2.8bn.

"The global economy is recovering... much more quickly than could have been anticipated," said Iata director Giovanni Bisignani. "We thought that it would take at least three years to recover the $81 billion (14.3%) drop in revenues in 2009," he added. "But the $62bn top-line improvement this year puts us about 75% on the way to pre-crisis levels."

--------
And that profit is despite a downwardly revised loss of $2.2 billion within the European airlines industry.\\

Well worth a look for anyone interested in Science. http://www.bbc.co.uk/programmes/b00729d9 Podcasts available to download and view again on the i player.

The tremor plot isn't refreshing for a while now?? http://hraun.vedur.is/ja/Katla2009/stodvaplott.html

Thanks, Parclair, last time I looked it was just a hazy blur, so I didnÂ´t know what to expect. I will have a longer look next time. Now itÂ´s hazy again.

#39 AFAICS, the plot is up to date; it IS getting crowded, though, as now one tick on X is 24 hours. Still, that plot is much better in putting things in perspective, as every tiny jump does not generate huge excitement, as does the short-time plot with its ever-changing amplitude scale.

There's a really nice cloudscape at Turrialba right now. Looks like a healthy steam billow as well from the crater, though it might just be clouds forming.
http://www.ovsicori.una.ac.cr/videoturri.html

Umm... okay, a plot for the Kat scratch fever. June Quakes to date, cross section looking North - Eyj to Kat.

http://i45.tinypic.com/z7dat.png

Tungurahua shows intense activity and generates huge explosions
www.hoy.com.ec - 07/Junio/2010 | 14:23
The Tungurahua volcano today generated a loud explosion, throwing ash, gas and rocks, leading to the possibility of raising the danger alert in areas of risk, officials said.
"There was a dry blast, gunfires were heard, some very strong. Fortunately, the explosion was not followed by the sounds associated with emission of incandescent volcanic material," said Gorki Ruiz, the Geophysical Institute (IG).
He added that, within the mountain, 135 km south of Quito, a lava lake is forming, which may cause flows to go down the northwest flank, where several villages are located.
The Emergency Operations Center (COE) in the province of Chimborazo shall meet "in order to analyze the possibility to change the alert level from yellow to orange for high-risk sectors, if the increase in the eruptive process persists", said turn National Secretariat of Risk (SNR).

@Lurking, do you believe the pattern we see "loosely" under Katla is representing the magma conduit up to the surface? It does look a bit like that compared to the dots under Eyja, at least I think so. What can be interpreted from these plots, is it anything like a "earth map"?

@43 Hi lurking,

16 or 17 under Eyja, 4 under Katla and 4 between.And we are only on the 7th of June.

I wonder what the full tally for May was like ?

Not at home, so only a short post - an Icel./Eng. micro-dictionary, right off the top of my head (assisted by the 'pedia and the Science Web (visindavefurinn.is)):

Aska, Ã¶sku - ash
Brennistein(n) - sulphur
BrennisteinstvÃildi - sulphur dioxide
Eldgos, gos - eruption(s)
EldgosiÃ°, gosiÃ° - the eruption
Eldgosin, gosin - the eruptions
GervigÃgur - pseudocrater
GÃg(ur) - crater
GÃga(r) - craters
Gjall - scoria
GjÃ³ska, gjÃ³sku - tephra
GosÃ³rÃ³i, gosÃ³rÃ³a - volcanic tremor; tremor b/c of eruption
Hraun - lava
::apalhraun - a'a' lava
::helluhraun - pahoehoe lava
Hraungos - effusive eruption
Hraunkleprar - lava splatters
HraunkÃºla - lava bomb
HraunkÃºlur - lava bombs
(Hraun)kvika, -kviku - magma
(Hraun)kvikan, -kvikuna - the magma
Ildi - oxygen, oxide
JarÃ°frÃ¦Ã°ing(s|ur) - geologist
JarÃ°frÃ¦Ã°inga(r) - geologists
JarÃ°skjÃ¡lftar, skjÃ¡lftar - earthquakes, quakes
JarÃ°skjÃ¡lfti, skjÃ¡lfti - earthquake, quake
JarÃ°vÃsindamaÃ°ur - geoscientist (literal translation)
JarÃ°vÃsindamenn - geoscientists (literal translation)
Kolefni - carbon
Kolvetni - hydrocarbons, carbohydrates
KÃ¶fnunarefni, nitur - nitrogen
LÃparÃt - rhyolite
Lofttegund - gas (lit.trans. is 'air type')
Lofttegundir - gases
MÃ³berg - tuff
ÃrÃ³i, Ã³rÃ³a - tremor
Sprengigos - explosive eruption (incl. phreatic)
StuÃ°laberg - columnar basalt
SÃºrefni - oxygen
Tefra - tephra
Vatn - water, lake
Vetni - hydrogen
Vikur - pumice
Ãeytigos - plinian eruption
Ãyrla, Ã¾yrlu - helicopter
Ãskufall - ash fall

Unlike English, the article is suffixed, and may vary with plurality, case, gender and the goose chase factor.

(So much for a short post...)

Pity in a way that sulphur is now mostly derived from non-volcanic sources; someone should write a book on the history of humanity's ideas over the years for collecting it from active or potentially active volcanoes. Schemes either hair-raising (Popocatepetl, Vulcano, White Island), hare-brained (Mt Adams, Davidof) or plain strange (Masaya: putting funnels over crater fumaroles and piping the gas down to a chemical plant at the foot of the volcano) Any offers?
(only joking)

@43: Now you've got the picture! This is what Haroldur was referring to in his blog, what...10 days or so ago!

Fissure extensions as probable sources of magma intrusion that might be feeding Eyjaf. Maybe Katla later on, once the pressure gains enough 'umph' to overcome what we might call 'closure kinetics' (very large force-moment couple acting horizontally and in opposition to vertical pressure on the relict MAR fissure system).

Go on, put back the approximate locations of Eyajaf and Katla on your graphic...

We need you to also mark the location of Godabunga.

Pretty please.

Thanks, Reynir. We've been needing that geology term translation help for ages.

The sulfur mining story is even scarier considering raw sulfur is basically a waste product in the US because desulfurization efforts in the oil/gas industry have swamped demand.

@Adrian,Dorset, UK [46]

May? The whole month? NP. Roughly the same layout as the June plot, but greater depths.

http://i47.tinypic.com/jgnqjs.png

@snotra viking, sweden [45]

I can't really hazard an authoritative guess. Passerby. JÃ³n FrÃmann, Erik Klemetti (and others) are far more qualified to make a supposition about what's going on down there. All I really do is play with the dots and read what I can find. I have seen texts indicating that there is some sort of connection to Katla, and there is an odd diagonal alignment of sparse quakes that trend toward Katla's crater... but that's about all I can say.

FYI, when I'm not fiddling with the Quakes in Iceland, I'm juggling benzene concentration estimates for the Oil Geyser southwest of here... mostly it passes the time while I stare at BP's Oil-Cam bot.

#50: I have been intending to do this for a while. I just had a reminder upthread.

@Passerby [49]

Okay.. Jun plot pulled out wider. Latitude depth is 63.3 to 64.75 in order to get both volcanoes and the area between. View is to the North.

http://i46.tinypic.com/2qsze5t.png

For those how missed my comment on the EyjafjallajÃ¶kull blog post. IMO has posted new information on what is going on in EyjajallajÃ¶kull.

http://en.vedur.is/earthquakes-and-volcanism/articles/nr/1884

Passerby, I misread your post.

I need a good lat and lon for Godabunga station in order to get it on the plot or else I'll have to eyeball it. The ISGPS gives me one of those "Page not found" results when I try to get the station specifics. I do have it stuffed away in a pdf somewhere in the directory, but I haven't indexed it so I'm not sure which one it's in.

In the meantime, on the June and May plots, Eyj is on the left, Katla is on the right.

@52 Lurking,

Brilliant stuff,please keep it coming as needed !

@49 Hi Passerby.I also remember Haroldhurs post and totally agree with your observations. The previously tenuous link between Eyja and Katla may not be so tenuous after all. I know this is pure conjecture but nevertheless....

@47 Hi Reynir,

Thank you so much for the translations:makes things a little clearer !!

@ Passerby

Okay.. I found the reference.

The position given is -19.32236 63.65976 god 2006 July 25 from "Seismic Signs of Magma Pathways through the Crust in the EyjafjallajÃ¶kull volcano, South Iceland" by Sigurlaug HjaltadÃ³ttir, KristÃn S. VogfjÃ¶rÃ°, Ragnar Slunga.

I used a vertical line since I don't have the altitude.

http://i46.tinypic.com/kf021k.png

#58 @Lurking: You are amazing, thank you very much, indeed!

Ah nice, Lurking, no surprises. Your previous graph helped underscore tectonic setting and magmetic chemical difference in the rift-ridge systems of the central hotspot EVZ (Grimsvotn and Bardarbunga, etc) and the interplate-boundary zone (that includes Hekla, Eyjaf and Katla).

Two different animals (crustal thickness, underlying relict crust and major acting forces at each volcanic center).

Haraldur is a smart cookie. He had his kid throw everything but the kitchen sink into last years masters thesis. Insightful.

Lurking...Didn't you plot May's EQ data in the same way? Not the cube, but a flat representation? Want to know if it has the same interesting pattern over depth.

@ Passerby [61]

Yes I did. Here's the link again.

i47.tinypic.com/jgnqjs.png

And, since you're on a roll, here are a couple more that I tried my best to get into the same boundaries (Latitude and Longitude). Do mind the depths, they probably won't match the colors in the other plots.

2007 all quakes

i46.tinypic.com/ixzafq.png

2008 all quakes

i50.tinypic.com/6h3rx5.png

I don't have 2009 data, I had to disassemble the Google Earth KMZ files from hraun.vedur.is/ja/google/index_en.html to get these. The 2009 set had no data.

(note: http stripped to dodge the spam filters)

Haven't had a chance to get on much, but I wanted to thank Lurking for the great visuals. Very informative and helpful.

Long Valley is going bump again today. A 3.2 and a 3.0 followed by a small flurry of smaller quakes all in the past hour or so.

http://earthquake.usgs.gov/earthquakes/recenteqsus/Maps/special/Long_Va…

This one is more of a look at what sizes of quakes occur where in Iceland. The data is from SIL ( hraun.vedur.is/ja/ymislegt/storskjalf.html )

Of note is that the area north of Katla and EyjafjallajÃ¶kull is capable of some pretty nasty ground movement. This probably explains (in part) why Hekla, Katla and friends are so active over the historical record.

Color indicates magnitude.

http://i49.tinypic.com/8yrgv7.png

@ Jen [64]

And again it seems as if there are two separate quake stacks in Long Valley.

From a previous article I saw that the Northern group of quakes is next to a fault that may or may not be next to a possible magma area. This batch looks to be in the same area. I don't know what it is, but here is the spatial arrangement of the quakes.

http://i46.tinypic.com/t8xbis.png

Whoah... I botched that one. Ignore the pic, one axis is backwards.

Use this graphic, same discussion.

http://i45.tinypic.com/1o14bd.png

I have a question for those watching Turrialba, with time to answer: I suppose the night view is a thermal cam like the FLIR cam at Mila. How about the glow? Is it from hot steam or is it lava? The plume was bigger today and the night view looks pretty impressive.
http://www.ovsicori.una.ac.cr/videoturri.html

Lurking: actually I think this particular stack of quakes is to the south of the ones that were going on two weeks ago (those were north of the caldera) this one is within the caldera boundary in the Mammoth Lakes region. Unless you meant the same area more broadly.

@40 Snotra, I believe you are in Europe? Try looking at the 2 Hawaii lava lake cams when you get up in the morning.

http://volcanoes.usgs.gov/hvo/cams/

The lava lakes (H from overlook and the P cam) are best seen during the Hawaiian night. During the days, vog tends to get in the way of viewing so I look at the H from HVO and TEB from P. (I'm writing this at 3:00 UTC. I estimate that Hawaii will be dark in about 4 hours.)

@43 Lurking. Wonderful plot. Thank you. I'm going to start watching the webcams again. ;-)

@47 Reynir Thank you for the quick dictionary. Rah!

@68 Renato thanks for the heads up on Turrialba. I think it's a regular camera, what we're seeing in the "white" areas are the eruption itself. I've not really looked at it today. Is there a city off to the right? The whitish dots on the right could be city lites or lava. (I'm leaning to lava).

To everyone, I really appreciate the cam watchers. I can only have 3 windows open for cams without crashing my system, so alerts are great. I promise to alert whenever I see anything. Whoohooo!

Heh. As my system was grinding out my previous post, I went to Salon.com to get the latest off the wire. Salon staff wrote:

Complete with the fools on the hill.

Diane, NoCal. I've decided. I like the new USGS California Quake Maps. As one zooms into the quake area, the faults are named! Way cool;-)

For those who might be interested, here's the California/Nevada Map, click on the area you're interested in, until you reach the info about the quake. Roll your cursor over the fault line, and the name will appear.

http://earthquake.usgs.gov/earthquakes/recenteqscanv/

#68 @Dan - Dan, Oil Beach Florida (???) - Come on! Switch this your nick. I'd pick Dan, Florida Margueritas, instead! :)
I've been following the devastating news on the oil spill. Hope you guys be courageous, this is going to be a long journey to recovery.
#70 @Parclair: Thank you for your kind response! It's reassuring for us, lurkers, to have support from others. I'll keep on posting my observations - have a good RAM here. :)
As I've already said before - this blog is terribly addictive!
THE BEST!!!!

OOOPS I managed to cancel out the salon quote with my ignorance of HTML tags-- the quote is:

After a May 27 explosion -- which killed a reporter who drew too near to it -- Guatemala's Pacaya volcano is drawing thousands of tourists to see its fiery rivers sloping down the mountain. Reports say that local guides are seizing the opportunity, and for as little as $1.25 a head, taking the awed out-of-towners around the closed Pacaya National Park and through a private park to get a firsthand view of the action. All of which has officials freaked out. Said the country's emergency response spokesman: "This is dangerous."

Sorry for the babbling. I'll be quiet now. ;-p

Regarding Turrialba, the lights in the distance are city lights, not lava, and the glow on the steam cloud is reflected glow from an incandescent vent. I was at Turrialba recently and it was putting out an impressively large gas plume.

@75 Mike-- To me, it appears that there are splatters that could be strombolian in nature. I agree that there's lots of reflection going on, but every so often there are distinct bright little lites in the glow.

Thanks for the heads up on the city lites. Looks like watching Los Angeles CA from the top of a hill. ;-)

#74 #75 #76 Thanks for the posts. I tend to agree with the reflected glow hypothesis but it's also noticeable that this eruption has intensified since yesterday, so I wouldn't rule out that what we are seeing is the real thing.
@ mike lyvers I envy you for the opportunity to watch this volcano from close, but I'm not sure that I would be bold enough to get as close as those people are doing in Guatemala. No way!
BTW: EQ Under Eyjaf: Tuesday
08.06.2010/02:53:22/63.609/-19.494/4.5 km/0.8/30.18/7.6 km S of BÃ¡sar

Sometimes I get the impression that EQs come all in a bunch over Island. It was quiet, and then, suddenly, little red circles showing all over the place. You can actually SEE rifting through the country, I daresay.

@73 Renato
Sounds like a plan. :)

#79 LOL!!! :)
Dan, whenever you come to Rio I'll introduce you to our famous "caipirinhas" and I'll show you different versions of "ManhÃ£ de Carnaval".
I warrant you I didn't drink any, but still, I can see the "floating city over Turrialba" and "the live rifting across Iceland". :)

Ok, fellows, enough for today.
Hope I'll find time to do some more lurking tomorrow! G'Night/morning!

@Jen [69]

Bit of both actually...

Profile view looking East, May and Jun on same plot

http://i45.tinypic.com/24edzle.png

Same set, perspective view looking North.

http://i46.tinypic.com/2rd9qtt.png

Large dots, my eyes are messing with me.

This is mainly for those who care... sort of a ramble on my part. Whats it mean? Beats me.

First, you can't directly compare these two plots. The Iceland plot is the current 15 minute average quake energy. In other words, all the quakes in a 15 minute window, converted to Joules, summed and divided by the number of quakes. Then I ran a 25 hour smoothing window across that. What I get shows what appears to be a general decline in quake energy in Iceland for now. Natch, this can change in short order.

http://i50.tinypic.com/2r5q3w3.png

Next, one that is a bit more difficult to get a grip on. While the data source for the first plot is the en.vedur.is/earthquakes-and-volcanism/earthquakes/ site, and uses whatever shows up, the next plot is from the USGS site, and ONLY USES quakes over magnitude 6.0. In part, this is because of the large quantity of data, and secondly it stretches back from 1973 until the present. Since technology has changed over the years, the increase in the number of small quakes will go up. My logic is that Magnitudes 6.0 and above are less likely to go unnoticed. Even with that, there is a chance that more recent quake reports will catch more data and arbitrarily skew the data. Keep that in mind when looking at the chart.

This chart uses the same method as the first one, but uses a 30 day increment and a 13 month sliding window for smoothing.

The general trend is up... with the caveats I mentioned above.

http://i45.tinypic.com/2q0tt2h.png

I took a look at the plots at http://hraun.vedur.is/ja/Katla2009/stodvaplott.html and I think it shows that the HVO station does not really show the same events as the others, closer to EyjafjallajÃ¶kull: the relatively prominent spikes on the others are not visible on the HVO plot at all.

I think HVO shows tremor from MyrdalsjÃ¶kull - it's a living glacier, after all; it's summer, so the melting must cause settling in the ice; and HVO is situated on the south side of the glacier, quite close.

@ 83 love your work Lurking. very interesting stuff.

re the global seismic energy plot what would be the effect of eliminating quakes of M8 and above? Would that remove the upwards trend?

Perhaps the plot is simply skewed by the recent bout of mega quakes (Sumatra and Chile)

Just passing by and found this advisory from PHIVOLCS:
Taal Volcano Bulletin
08 June 2010
8:00 A.M.
This is a notice for raising the alert level status of Taal Volcano from Alert Level 1 to Alert Level 2.
http://www.phivolcs.dost.gov.ph/index.php?option=com_content&task=view&…

The lovely, lovely plot, #83 shows the global temperature effect on glacier melting and a shift in surficial anisotropy (thermal flux in lithosphere shallows).

The driver for this warming trend may in contention to some. It is irrelevant for our purposes here, so we'll stay away from that topic.

The other interesting plot of historic large quakes north of the Eyjaf-Katla area (which you must rotate to correct lat long positions) clearly indicates the tectonic collision intersection of the EVZ and SISZ. Very large forces acting here.

Now you wanted to know the meaning of the shorter averaging scale (15 min EQ map). As you would expect, its got a lovely lovely direct correlate to the historical global temperature trend, in the heating of the ionosphere.

For that, you must look up, not down.

Mulakot webcam video of yesterday's "deposited ash re-entrainment from convection winds" dustdevils!http://www.youtube.com/watch?v=txrCu-lZ0F8

Many thanks to Lurking for the labor-intensive work behind the the suite of timely EQ data plots, posted yesterday and today.

bonjour Ã tous. j'ai une question concernant le volcan Grimsvotn. Depuis quelques jours je constate pas mal de tremblements de terre dans la zone.Est ce un signe d'une Ã©ruption sur le moyen terme?

@88. That is probably one of the most interesting video capture movies posted here, showing the counter current wind movements on the mountains versus the valley, and its cyclonic influence, in the dust devils that flit across the screen.

Many thanks for your kindness in image capture and provision of the video here.

@ Reynir. is (no. 47)

Thanks for all your hard work - absolutely super!

Looks like it would have taken you some time to put all that together, and it may prove very useful for many of us.

( Am now going to catch up on all these other posts.)

@Kannaboy, nÂ°90
Bonjour Kannaboy, la langue de ce blog Ã©tant l'anglais, il vaudrait mieux reposer votre question dans la langue de Shakespeare si vous voulez une rÃ©ponse :-)

Babelfished #90
>hello with all. j' have a question concerning the Grimsvotn volcano. For a few days I have not badly noted earthquakes in the zone. Is this sign d' an eruption on medium term?

Babled back via translator:

Non. NumÃ©ro Les tremblements de terre peu profonds sont probablement dus aux tensions de calotte-cratÃ¨re qui dÃ©place des systÃ¨mes de cratÃ¨re-fissure. Il fait plus chaud en Islande, comme vous pouvez voir par les jolies fleurs qui sont apparues sur le webcam de Mulakot. De tremblements de terre le mouvement plus profond de magma peut-Ãªtre, mais lui n'est pas probable qu'une Ã©ruption se produise chez Grimsvotn en ce moment, Ã moins qu'il y ait un dÃ©gagement soudain de l'eau de fonte de secondaire-calotte glaciaire.

@ Kannaboy 90

Bienvenu chez nous!

Je suis desolee - ma langue maternelle est l'anglais et de plus le truc pour faire marcher des accents me manque mais je vais essayer de vous repondre comme meme:

Au sujet des tremblements de terre a Grimsvotn:A l'heure actuelle, le volcan Grimsvotn n'est pas du tout a l'une en Islande donc, je suis tout d'accord avec Passerby.

En revanche, le volcan Bardabunga se situe pas tres loin de lui! Des 1998, ce volcan, situe a la meme region (sous le glacier de Vatnajokull)a vu un haut de tremblements de terre surtout pendant les mois derniers ( augmente malgre le changement de la saison).

Cliquez-vous ici mais il faut le traduire avec google:http://www.seismology.harvard.edu/projects/unusEQ/Iceland/index.html

Alors,en ce mmoment, on voit que Eyjafjallajokull est en train de faire un peu de refroidissement(!!) mais comme d'habitude au sujet des volcans,cette situation pourrait changer en un clin d'oeil!

Que faire? Rien faire. Soit une eruption du volcan de Eyjafjallajokull ou soit celle d'une autre il nous faut qu'attendre...

@ Kannaboy et Irna 93

Soit creee en francais ou en anglais votre correspondance marche ici - cet un blog mondial, n'est pas?

Trombley came up in a Volcano listserv email last year - Lee Allison posted it on his blog, and I did a post last year around the time the email went out. (I think I emailed you about it at some point, too, but I could be wrong.)

i think all this tremor earthquakes Volcanos all link to the planetary alignment gravity magnetic field ect.... Ive been following all this since April but earthquake around the world for a year now and since Friday 11th June 2010 Katla showed increased quakes in the last 24 to 36hrs on the 12th June a planetary alignment Jupiter-Saturn-Earth relation Full-moon G-factor mod+ again on the19th June same again but F-Q Moon G-factor =mod++,04-07-10 same but L-Q Moon then the 31st july10 Jupiter-Saturn-Mars-Venus-Earth relation Full-moon,G-factor mod+++ now see if you get a increased in Earthquakes at these times why because if KATLA GOES OFF she more likley to go off in sept10,Oct10,NOV10 Around the 21/22/23rd September very high G-factor dangerous planetary phase,if not somewhere in the world a big earthquake will hit, because HAITI EARTHQUAKE was link to a planetary alignment with was published and also CHILI EARTHQUAKE ;year 2010/planetary/possible Earthquakes and Tsunami warning,volcanic activties all taken from the EUISQR EUROPEAN INSTITUTE FOR SPACE QUANTUM RESEARCH OR Http://www.supernovae_energy.com/2010_haiti_earthquake.htm

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