caldera
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 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…
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 25, 2008
If anyone has been watching the earthquakes worldwide today, you might have noticed that there have been three >M2.5 earthquakes in the Yellowstone Caldera today at depths <10 km. Not to say that it is anything, but just something to note.
eklemetti | September 21, 2008
It seems that a new fissure eruption has begun at Piton de la Fournaise on Reunion Island in the Indian Ocean*. In fact, the report goes onto say that a small lava lake has formed at the main crater of the eruption. This marks the first eruption at Piton de la Fournaise since March 2007.
Piton de la Fournaise is a large shield volcano associated with the Reunion Island Hotspot. The volcano has frequent eruptions, mostly in the form of effusive lava flows of basalt, similar to the Hawaiian volcanoes. This could be an interesting new eruption because the initial eruptions suggest this is a…
eklemetti | September 7, 2008
I wanted to post the new MODIS image of Chaiten that caught the volcano erupting on September 3. I won't go into too much details, there are a lot of great updates over on the Volcanism Blog, but needless to say, the volcano is still very active, producing tall ash columns (you can see the ash blanket around the volcano in the image above as the plume drifts off to the northwest), earthquakes and pyroclastic flows as the dome in the caldera continues to grow. I'll be interested to see what geologists know about the eruption and volcano when the AGU meeting rolls around in December as there…
eklemetti | September 2, 2008
Two volcanoes on the island of Luzon look like they might be primed for activity, at least according to PHILVOLCS, the Philippine Institute of Volcanology and Seismology. Both Mayon and Taal (above) are showing signs of increased seismicity. Only Mayon is actively steaming right now and the volcano had a mild ash eruption on August 10 as well. Officials in the Philippines have both volcanoes on Alert Level 1 (potential activity).
Taal is actually part of a bigger system that occupies a 15 by 20 km caldera. The island where most historic activity has occurred is made up of a series of…
eklemetti | August 14, 2008
I'll be brief (as I'm in the middle of moving), but I did see a report that activity at Chaiten is increasing yet again. This seems like the operating mode for this volcano, with a waxing and waning of intensity, since the volcano started erupting on May 2. The latest report indicates renewed ash emissions producing an ash column that reaches ~20,000 feet (4,000 meters), with ash falling on nearby areas. There is also mention of some increased seismic activity at the Chilean caldera. The picture above shows the extent of the mobilized ash and volcanic debris that has wiped out much of the…
eklemetti | August 9, 2008
The folks up in Alaska have a lot to watch these days in the Aleutians, with three volcanoes erupting right now. Just a quick update on the current activity:
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Kasatochi: The eruption that started Thursday and produced 45,000 foot ash columns has quieted by Saturday, but there are still moderate (M=5) earthquakes being recorded near the island (above, before eruption).
Okmok: Ash from the month-long eruption is falling on islands near the caldera.
Cleveland: Activity at Cleveland has quieted to the point that no ash column was spotted on Saturday.
eklemetti | August 7, 2008
The Okmok Caldera eruption is still going on, almost a month after it started. The latest USGS/SI Weekly Report states:Â
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Strong volcanic tremor on 2 August prompted AVO  to raise the Volcano Alert Level to Warning and the Aviation Color Code to Red. Cloudy conditions prevented satellite observations. Later that day, AVO geologists in the area reported that ash-and-steam plumes rose to minimum altitude of 6.1 km (20,000 ft) a.s.l. The seismicity decreased and the Volcano Alert Level was lowered to Watch and the Aviation Color Code was lowered to Orange. Observers in Ft. Glenn on Umnak…
eklemetti | August 1, 2008
So, August rolls in and who would have thought in early May we'd still be talking about the Chaiten eruption with such intensity. Jorge Munoz of the SERNAGEOMIN is wondering whether the current eruptive activity and seismicity at Chaiten is a precursor to the end of the "first cycle" (as he calls it) of activity that started in May or that this is all leading up to another major explosive eruption (the "plugged volcano" scenario). The most puzzling part of the current activity is the high amount of seismicity: 105 earthquakes over the last few days, some of them up to magnitude 4. The…
eklemetti | July 28, 2008
After raising the alert level at Okmok Caldera in Alaska to Red over the weekend, AVO has reduced it to Orange. Reports have the volcano producing ash columns of less than 20,000 feet versus the 35,000+ foot columns earlier in the weekend. At the same time, Cleveland Volcano is continuing to issue ash from the vent and signs are still there for a lava flow. Both of these volcanoes look like they should continuing erupting into the near future.
eklemetti | July 27, 2008
There haven't been any major developments volcano-wise over the weekend, just a few updates on some current rumblings:
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Soufriere Hills (Montserrat) coughed up more ash, producing ash columns to "thousands of feet" according to reports from the MVO. The eruptions/explosions were centered at the lava dome on the summit of the volcano, Seismicity has also increased, suggesting that a larger eruption might be in the works.
Chaiten continues to worry Chilean geologists. Although the eruption seems to have reduced in intensity over the weekend, the fear of a blockage that could lead to a…
eklemetti | July 25, 2008
ONEMI, the Emergency Office of Chile, is expressing concerns that Chaiten might be readying an even bigger blast than what we've seen already in the past few months. In particular, ONEMI direction Carmen Fernández is concerned that the volcano might have a major explosion with accompanying ash fall and pyroclastic flows. They are pointing to the increased seismicity at depth under Chaiten as potential evidence that the conduit to the surface is partially blocked, and thus building pressure for a large explosion - think Augustus Gloop in Charlie and the Chocolate Factory if you want a…
eklemetti | July 25, 2008
The Alaska Volcano Observatory is reporting that both current eruptions in the Aleutians - at Okmok Caldera and Mount Cleveland - are showing signs of a lava extruding from the vent. Thermal anomalies have been imaged at the vents of both volcanoes, although no lava has been seen thus far. Both volcanoes continues to emit ash and steam.
The news that lava is erupting isn't really shocking (it is a volcano, you know). Many times, these eruptions begin with a "throat-clearing" phase of ash and volcanic debris being erupted from the vent. If the magma is still rising after these initial…
eklemetti | July 24, 2008
I am beginning to feel like a broken record, but the latest reports from Chile indicate that the ongoing eruption at Chaiten is ramping back up again, almost 3 months after the initial eruption began. As usual, the nitty-gritty details are limited, but reports of increased ash emissions and seismic activity are heralding this increase in activity.
For certain, Chaiten is one of the most important eruptions in any of our lifetimes. This is really not because of the amount of material that has been erupted (although when all is said and done, it will be a significant volume), but rather for…
eklemetti | July 21, 2008
Just when you thought it was exciting enough in the Aleutians, word comes in that Cleveland Volcano is erupting as well. Cleveland is a very noisy volcano on Chuginadak Island, having last erupted in February (although it hasn't been updated on the GVP page). Aircraft have been warned about both eruptions in the Alaskan island chain. Along with the eruption of Okmok Caldera, the AVO has their hands full watching these volcanoes. The latest on Okmok has a 24,000 foot ash column continuing to be emitted from the new vent.
eklemetti | July 20, 2008
It has been a while since we've seen a Chaiten update, but today there is a report that LanChile has had to cancel flights to Puerto Montt due to ash from the volcano. Chaiten has been erupting since early May, so now we're almost 2 1/2 months into the eruption - quite a feat for such a large eruption! The report also mentions that some residents of the town of Chaiten have been able to visit their homes to collect belonging and the government might just try to rebuild the town in an entirely new location. The USGS plans to send geologists to the volcano later in 2008 or early 2009 to survey…
eklemetti | July 20, 2008
I'm back from my conference and will hopefully be getting back to a regular schedule!Â
In the meantime, the biggest news is still the eruption of Okmok Caldera in Alaska. The latest news has the eruption still going strong and the USGS predicting it will continues for potentially weeks to months. The eruption is apparently from a new vent on the caldera floor as well. Looks like the current eruption might be a VEI 4 (or thereabouts) eruption based on what I've heard from USGS scientists.Â
The largest hazard posed by Okmok right now is to air travel, this during a time when the Alaska…
eklemetti | July 15, 2008Here's a stunning shot of the current eruption at Okmok Caldera in Alaska (brought to us by National Geographic).
Personally, I think the best part is the fact that this was shot by an Alaska Airlines pilot! Talk about "to the right of the plane..." fodder.