Okmok

Shiveluch volano in Russia. Just like last summer seemed like a busy time for the Aleutians (Cleveland, Okmok and Kasatochi), this summer could be dubbed the "summer of Kamchatka-Kurils" (alright, it isn't that catchy, sorry). The biggest news was/is, of course, the sizeable eruption from Sarychev Peak in the Kuril Islands, but not to be outdone, Shiveluch on the Kamchatka Peninsula has starting playing catchup. KVERT is reporting that Shiveluch produced a 7 km / 23,000 foot ash column on Monday, with increased seismicity to go along with the explosions. These explosions are generating the…
Count this as your mini-update for Redoubt, with the news being no news. Even AVO seems a little bored with Redoubt lately (not to say they aren't watching it as vigilantly as ever) as their last three updates have been exactly the same: Redoubt volcano has not erupted. Seismicity is low, but above background levels and consists mainly of small discrete earthquakes. Night has fallen and no image is visible in the webcam. However, down the road (arc-wise) in the Aleutians, AVO has raised the alert level at Okmok Caldera. New volcanic tremors were felt yesterday at Okmok, averaging about one…
I was chatting with a fellow from AVO and he called the simultaneous eruptions of Kasatochi, Cleveland and Okmok a "once in a millennia" event. So, enjoy it! He also mentioned that the Kasatochi eruption released the most sulfur dioxide into the atmosphere since the 1991 Pinatubo eruption ... but we had an idea of that already. And who knew that there has been uplift at Uturuncu in Bolivia? I sure didn't, but Steve Sparks does.   More to come later this week when I can go to all the Chaiten posters.
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…
The current eruption at Kasatochi is causing a lot of flight cancellations for flights from Alaska to points in the continental US. The ash is swirling its way around the Aleutians along flight lanes (see above), with the ash drifting southeast over the Alaska Panhandle and could hamper air travel in Alaska and Canada for days according to the USGS (although Alaska Air says it might start flying again later today). As for the eruption itself, not much new news beyond the initial impression that the volcano went from quiet to explosively erupting to produce at 35,000 foot (~10,000 meter) ash…
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:   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.
The Okmok Caldera eruption is still going on, almost a month after it started. The latest USGS/SI Weekly Report states:    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…
Finally, in a very slow week for volcano news, we find a report from the Alaska Volcano Observatory about concerns of another eruption in the state. Currently, both Okmok and Cleveland are erupting, and now AVO has issued a warning about Kasatochi Volcano on the island of the same name (~100 kilometers east of Adak, roughly near 175W on the map above). The volcano is the island - more or less - and any people on the small island are being evacuated due to increased seismic activity underneath the volcano/island. Not much is known about the eruptive activity at Kasatochi. The volcano does…
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.
There haven't been any major developments volcano-wise over the weekend, just a few updates on some current rumblings:   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…
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…
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.
I'm back from my conference and will hopefully be getting back to a regular schedule!  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.  The largest hazard posed by Okmok right now is to air travel, this during a time when the Alaska…
Here'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.
Sorry about the brevity of this update, but I'm exhausted. From the Alaska Volcano Observatory (AVO): At this time, based on AVO analysis of satellite data, ash is continuing to erupt from a composite cinder and spatter cone called Cone D in the eastern portion of the 6-mile wide caldera or crater of Okmok. It appears that the eruption is very water-rich due to interaction of rising magma with very shallow groundwater and surficial water inside the caldera. We have few direct observations into the caldera and details of the current event remain unknown. The current activity differs in…
Sorry about the delay with updates, I am actually at a meeting filled with volcanologists (of all things), so updates might be a little sporadic. A lot of news today about Okmok erupting in the Aleutians. The Alaska Volcano Observatory had this to say: The eruption at Okmok continues based on high levels of seismicity and ash continues to be erupted as indicated in satellite observations. Seismicity reached a peak at about 2200 Z (2:00 PM ADT) yesterday and has been gradually declining since. Reports from Unalaska indicate no ash fall in Unalaska/Dutch Harbor since last night. However,…
Okmok Caldera in Alaska's Aleutian Islands erupted today, sending an ash column to at least 30,000 feet. Very little news has been released about the eruption so far beyond this information about the eruption column and some bits about precursor seismicity. A number of flights to Unalaska Island were cancelled due to the eruption. I'll pass on more information when I get it. Okmok is located near Dutch Harbor, Alaska and is a large shield volcano with two prominent calderas at the top. In fact, whenever I see pictures of the caldera, I am reminded of what Crater Lake (Oregon) might look…