explosive eruption

  Klyuchevskoy has already had a busy year and now we have some recent photos showing a lava flow that is snaking down the side of the volcano. The website with the lava flow image has a pile of other great eruption photos of Klyuchevskoy over the last couple of years and well worth the time to look through them all - the volcano is definitely one of those classic arc volcanoes in both shape and activity.
Eruptions and earthquakes go hand-in-hand a lot of the time. It only makes sense as magma needs to move under the crust, causing movement (i.e., earthquakes). Additionally, any sort of explosions caused by the release of volatiles might cause earthquakes or even the collapse of an edifice (which in turn, shakes the earth). So, it is not surprising that the current eruption at San Cristobal in Nicaragua has produced earthquakes. The reports are relatively lacking in details, but San Cristobal is a typical Central America stratovolcano that produces frequent Strombolian style eruptions, which…
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…
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…
I just got back from a 4 day field trip to the Long Valley Caldera in eastern California, so I'm a little behind on posting. The field trip was great and I had a chance to see a lot of pumice, a lot of welded tuff (in the form of the Bishop Tuff, the large ignimbrite that erupted from the Long Valley Caldera ~760,000 years ago) and got to lead the part that looked at the Mono domes (too bad snow covered the Inyo Domes). Pictured above some puffed obsidian - the layers are obsidian and vesicle-rich obsidian - that were erupted, cooled, expanded and cracked (known as "breadcrusting"). This is…
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).
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…
Sorry 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   Location: Papau New Guinea Height: 688 m Geophysical location: Boundary of Australian plate and Pacific plate…
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…
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…
On Sunday afternoon, a large ash eruption occurred at Halemaumau Caldera at Kilauea. Not only did the volcano belch more grey ash than usual, but also red-hot incandescent material can be clearly seen being thrown from the vent during the vigorous eruption. The coolest thing about the eruption is that it was all caught on film by the USGS/HVO. Take a look (at three times speed) - this video is from the morning of October 12, but there are a series of video from the whole weekend on the website.
  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…
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.
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…
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.
It is always fun to me when we discover that a volcano long considered dormant or extinct has seen activity in the recent past. I bring this up because Mount Nantai in Japan, a volcano that was considered to have last erupted over 10,000 to 20,000 years ago (if not longer) looks to have actually erupted as recently as 7,000 years ago. This might not seem like a big different to some folks, but this definitely puts the volcano in the "active" category if this date turns out to be accurate. The volcano looks to have had a number of explosive ash and pumice eruptions along with some dacite lava…
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…
Whether this is a coincidence or not, I thought I'd mention a report of an earthquake near the crater of Nevado del Huila in Colombia. The earthquake is reported as a magnitude 4.6 and at a depth of 20 km (although that is only a rough estimate), indicating that magma might be moving up the conduit system under the volcano - or that it might be just coincidental seismicity in a seismically active area. However, Huila had recently become active for the first time in 500 years, so this could be a sign of new activity to come.
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…
I am back from my trek through the Oregon and California Cascades - including stops at Lassen Peak/Chaos Crags, Hood, Three Sisters and Crater Lake (an added bonus). I'll try to catch up on the volcano news I've missed and post on anything exciting that happened soon, but otherwise I'll be posting new news as it occurs. In the meantime, here's a picture I took of Rock Mesa (foreground) and South Sister (background) taken from the Pacific Crest Trail. Rock Mesa is a ~2,700 year old rhyolite flow that appears to have erupted multiple pumices and has some impressive flow banding of the rhyolite…