volcanic hazards
eklemetti | November 17, 2008
Redoubt Volcano, in Alaska, is one of the more troublesome volcanoes in the state. Not only is it relatively close to population centers, but it also lies directly within the aircraft corridors above the Aleutians for planes headed to Asia and beyond. This means that USGS and AVO geologists have to be especially vigilant in watching Redoubt's every move.
Currently, the volcano has been recently changed to a yellow (elevated) alert, due to increased steam/volcanic gas emissions (remember, the number one volcanic gas is water vapor) at the volcano. So far, there haven't been any reported…
eklemetti | November 13, 2008
Just a brief note, but today (November 13) is the 23rd anniversary of the disastrous lahar at Nevado del Ruiz in Colombia. Over 23,000 people died when a lahar, started by a relatively minor eruption of the volcano, swept down the river valleys the side of the edifice and destroyed Armero and Chinchina. The footage of rescue efforts after the lahar were devastating and heartbreaking (caution: linked video might not be for the faint of heart). Sadly, this disaster was mostly preventable as the citizens of these towns could have had at least an hour's warning to walk to higher ground, but the…
eklemetti | November 11, 2008
El Reventador, the composite volcano in Ecuador, has been producing explosions and ash for the last few days, so says reports from the country's  Geophysics Institute. El Reventador is only 100 km from Ecuador's capitol, Quito, and in 2002 the volcano blanketed much of the city in ash. However, the eruptions currently occurring are much smaller and limited in scope, producing ash and throwing incandescent blocks out near the vent (see above). No evacuations are currently planned. These types of eruptions are typical for El Reventador since 2002, with increased activity every few years…
eklemetti | November 6, 2008
One of Kamchatka's most active volcanoes is continuing to erupt. Shiveluch, in the northern part of the Kamchatka Peninsula in Russia, produced a 26,000 foot (~8,000 meter) ash column today (November 6) as the eruptions that started in 2006 persist. The reports suggest little danger to people living on the peninsula, however the ash column is causing problems with the air travel over the region (an important corridor for trans-Pacific travel).
eklemetti | November 6, 2008
Sounds like we're beginning to get a better idea of what is erupting in Ethiopia. Ghezahegn Yirgu, a geologist at Addis Ababa University, reports that Dalla Filla Dalaffilla Volcano is the source of the eruption. Again, the eruption is being characterized as "lava flows" rather than an explosive eruption, which may be surprising considering the amount of volcanic gases being released (see Boris Bechnke's highly useful comment). However, some mostly effusive eruptions have released a lot of volcanic gases in the past - see Laki, Iceland in 1783 - so a preponderance of flows at Dalla Filla…
eklemetti | November 5, 2008
In one of the most oddly worded articles I've seen from the BBC, a lava flow from Erta Ale an unidentified volcano in the Erte Ale range in Ethiopia has erupted a significant amount of lava. The headline states "Ethiopia volcano sets lava record", which is strange on multiple counts, but mostly because I'm not familiar with any "lava records", who might keep track of them and what, exactly, this "lava record" is. In fact, they don't even mention it in the article itself. They do, however, point out that lava from this eruption has covered 300 square kilometers, which is a decent chunk of…
eklemetti | October 31, 2008
After nearly a year and a half of little lava dome growth at Soufriere Hills in the West Indies, this past July 26th, the volcano erupted new dome material. Why do I remind us of this, you ask? Well, the Scientific Advisory Committee at Montserrat feel that the dome growth might be restarting in earnest:
Since August, any new supply of lava has been minimal. Thus while there is evidence that the eighteen-month long pause in lava dome growth may be coming to an end, it has not happened yet.
The most troubling event, in their minds, is the new activity at the Gages Wall vent, which means that…
eklemetti | October 27, 2008Sorry about the dearth of posts. It has been a busy week here in Davis and I've been a little distracted by the upcoming election. Combined with the relative lack of volcano news this week, the posting has been lackluster.
However, that being said, I will try to make up for some of it by starting my Volcano Profiles series that will bide the time between volcano news. I start with a volcano that was suggested by Eruptions reader Thomas Donlon: Rabaul.
VOLCANO PROFILE: RABAUL
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Location:Â Papau New Guinea
Height: 688 m
Geophysical location:Â Boundary of Australian plate and Pacific plate…
eklemetti | October 20, 2008
The headline for this entry sounds more dramatic than it is, but one of the last structures in the ill-fated Royal Gardens subdivision on the big island of Hawai'i finally met its fiery demise over the weekend. For those of you unfamiliar with the plight of the subdivision, Royal Gardens is part of Kalapana, and it was unfortunately situated quite close to the Pu'u O'o rift that has been erupting since 1983. Most of the subdivision has been overrun by lava flows since then, but one of the last two structures still being used was done in by the basaltic lava. The first link has a great map…
eklemetti | October 17, 2008
The only volcanic arc in the lower 48 states continues to be pretty darn quiet according to the USGS. The Cascade range that spans from Lassen Peak in the south to Mt. Baker in the north (and maybe Mt. Garibaldi in Canada) has been remarkably quiet in terms of eruptions for the last century. In fact, only Mt. Saint Helens and Lassen Peak have erupted since 1900 - and most of the volcano have shown very few signs of even coming close to eruption beyond minor seismic swarms, steaming or land deformation. This is in contrast to the reports from the 1800s that suggest that Hood, Shasta, St.…
eklemetti | October 16, 2008
Reports from Russia indicate that Klyuchevskoy, Russia's largest volcano, is erupting. It sounds like it might not be just a murmur as Alexei Ozerov from the Institute of Volcanology and Seismology of the Far Eastern branch of the Russian Academy of Sciences says the volcano is spewing ash, rock and gases. No real details on how tall the eruption column is, but the report mentions a hazard to aircraft in the area, which would suggest that the column is at least in the 3,000-5,000 meter range. Klyuchevkoy is part of the Kamchatka volcanoes in far east Russia and last saw a major eruption…
eklemetti | October 15, 2008
There isn't really much information in this report, but Galeras in Colombia has been put on "high alert" for a potential eruption. The volcano did emit a ~2,400 meter steam (and ash?) column today, but beyond this, it is unclear what else might be happening at the volcano.
Galeras is the most active volcano in Colombia, having erupted frequently in the past decade, producing mostly ash falls, ballistic bombs and other explosive volcanic products. It is also located within a few kilometers to Popayán (see photo above of previous activity), a city of ~200,000 people, making it a potentially…
eklemetti | October 13, 2008
The eruption of Kasatochi was a bit of a surprise to volcanologists who study the Aleutians, to say the least. The volcano itself has been quiet for likely over 100 years, but with relatively little warning, the volcano erupted over the summer, blasting ash (and a large amount of sulfur dioxide) into the atmosphere. We finally have some images of the destruction wreaked upon the island, and from the looks of it, the island is blanketed in grey ash from the eruption(s). Biologist who have worked on the island prior to the eruption think a significant number of auklets may be buried in the ash…
eklemetti | October 7, 2008
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UPDATE 10.9.08: This photo is not from the current eruption (see the comments below), so disregard any comments I might have about the current state of activity.
Contrary to some of the earlier reports, the eruption at Soputan in Indonesia might be more impressive than previously though. Pictures of the eruption (above) show a fairly healthy eruption column coming from the volcano, although it is hard to tell if the image is just an eruption column or a column with an associated column-collapse pyroclastic flow heading down the far side of the volcano (in the picture). The former would…
eklemetti | October 7, 2008
Nevado del Huila in Colombia continues to keep officials in the southeast region of the country on their toes as they wait to see what the volcano might do. There was increased seismicity over the weekend according to Jair Cardoso of the Attention, Prevention and Disasters Committee, along with minor steam and ash emissions. The Colombian geological survey, INGEOMINAS, will be sending experts (including Marta Calvache and Cesar Eduardo Lopez) to examine the current state of the volcano and try to decipher what state the magmatic system is in: ready to erupt or just gurgling away.Â
(Of…
eklemetti | October 6, 2008
There are a few brief reports of a minor eruption at Soputan in Indonesia. The reports from the Associated Press mention a small eruption column that reached ~1,000 meters and was accompanied by ash fall and explosions. From the sound of it, the eruption(s) are minor Strombolian types, common at arc stratovolcanoes like Soputan. Indonesia officials have warned people to watch for potential lava extrusion that might follow these explosive, possible "throat-clearing" blasts. Soputan was reported to have erupted earlier this year and has erupted frequently over the last decade.
eklemetti | October 4, 2008
Finally, after a rather quiet week, we have news that yet another Aleutian volcano is showing signs of potential activity. Redoubt Volcano was seen steaming away in a recent flight over the stratovolcano. When combined with reports of "booming noises" and the scent of sulfur it all points towards increased chance of eruption. However, AVO points out that they have not seen any increase in seismicity at Redoubt so far, making it difficult to predict exactly what the future will bring for the volcano. The volcano last erupted in 1990 and an eruption in 1989Â (above)Â produced a VEI 3 blast…
eklemetti | September 26, 2008
It has been awhile since we've talked of Chaiten, so I thought I'd touch upon "the eruption of 2008" (really, no one else is close). Spring time has arrived in southern Chile, and the Patagonia area has cleaned up a lot of the ash from the eruption (but not the town of Chaiten). National Tourism Service says that most towns and parks in the region are ready for tourists and even some tourist companies near Chaiten are good to go.
As for the volcano itself, the latest USGS update reports ash columns still being erupted and reaching up to 12,000 ft (3,700 meters), along with a "thermal…
eklemetti | September 26, 2008
Shiveluch in Kamchatka experience a small eruption today. Russian authorities reported a ~4,500 meter ash column with associated local earthquakes, likely related to the eruption. In the same article, both Karymsky and Klyuchevskaya Sopka (also known as Kliuchevskoi) are erupting or showing signs of increased activity.
Shiveluch is one of the many active volcanoes along the Kamchatkan arc that is on the far eastern side of Russia. It has been continuously erupting since 1999, mostly in the form of small explosions, pyroclastic flows and lava flows/domes - your typical arc volcano.
eklemetti | September 25, 2008
This might not be directly related to a volcanic eruption, but it has been picked up by a lot of news sources, so I thought I'd give it a mention. A report from researchers at University of Texas hypothesize that some very large coral boulders (up to 10 meters tall) that can be found on the shores of Tongatapu are, in fact, tsunami deposits. That is news enough, but they go on to say that the tsunami could have been volcanically triggered (i.e., started by an eruption or volcanic landslide). The corals are ~122,000 years old and a soil has formed on the corals, so the event was likely…