Dome
eklemetti | March 31, 2010As a volcanologist, I am partial to impressive lava flows, especially in volcanoes that erupt material that you'd think wouldn't produce big flows. For example, there are quite a few volcanoes in the Chilean Andes that erupt dacite lavas, which are relatively viscous (sticky), so you might expect it to erupt explosively. However, you can get large dacitic to rhyolitic lava flows, quite commonly, and these large flows are called coulées (a "volcanic dome flow").
Lllullaillaco volcano on the Chile/Argentina border. Note the very prominent coulée with flow levees. Click on the image to see a…
eklemetti | March 10, 2010Did I mention its a busy week?
The lava lake at Erta'Ale in 2008. Image courtesy of Stromboli Online.
Our Icelandic saga continues, with more earthquakes and more speculation/information on the parts of Eruptions readers. Keep up the discussion - I'll be fascinated to see who turns out to get closest to what actually happens, prediction-wise. The seismicity has quieted somewhat again in the last 12 hours, so we wait eagerly to see what comes next. Remember, Iceland is the land where volcanoes helped change history, so it is always fun to talk Icelandic volcanism.
The NASA Earth Observatory…
eklemetti | December 15, 2009
The new dome erupting at Mayon in the Philippines on December 14-15, 2009.
It appears that the eruption that PHIVOLCS had been waiting for at Mayon has arrived, with new magma reaching the surface and spilling down the slopes of the volcano. Or, as CNN International put it:
The island nation's most active volcano after it oozed fiery lava and belched clouds of ash.
People do love the idea of fiery, oozing lava, don't they?
Anyway, PHIVOLCS has raised the alert status at Mayon to Level 3 (eruption in days to weeks). This new activity has prompted the evacuation of at least 47,000 people in…
eklemetti | November 1, 2009All the news to start the week:
Galeras with a grey ash-and-steam plume behind Pasto, Colombia.
Well, after my article on Friday about Colombian volcanoes, Galeras must have decided it was left out. The volcano has been placed back at alert level Orange/II (eruption in days to weeks). An increase in seismicity and sulfur dioxide emissions (in spanish) prompted INGEOMINAS to put Galeras back on higher alert, but now the country has two volcanoes (Galeras and Huila) that could be erupting in the near future.
Back in the Philippines, there is new evidence that Mayon has a new dome forming at…
eklemetti | October 8, 2009Chaiten has made it back into the news in the past couple days, both with new events at the caldera and with findings from the initial blast in May 2008. Here goes:
Chaiten erupting in 2008.
Third Dome Spotted
The latest USGS/SI Weekly Volcanic Activity Report mentions that over the last week, Chaiten experienced what was likely a significant dome collapse of one of the two domes growing in the caldera. People living close enough to the volcano to see the ash plume noticed it became larger and darker on September 29th. Afterwards, visual observations of the caldera by air confirmed that a…
eklemetti | September 11, 2009
Undated photo of Shiveluch volcano in Russia.
In case you haven't seen the report yet, Shiveluch in Kamchatka has gone, as they say, "non-linear". KVERT has raised the alert level at the volcano to "Red" with reports of many strong explosions and an ash plume of >32,800 feet / >10 km. This all suggests that the volcano might have experienced [WARNING SPECULATION] a massive dome collapse followed by rapid decompression of the magma under the dome - causing the plinian eruption that seems to be underway. The size of this eruption plume will definitely have some effect on air travel over…
eklemetti | August 26, 2009The slow summer for volcanic eruptions continue. Only 11 updates in this week's USGS/SI report. Thanks again to SI's Sally Kuhn Sennert for compiling the news!
Highlights this week include (not including Kilauea) include:
Tungurahua in Ecuador produced some minor lahars on August 21 to go with steam-and-gas emissions.
Popocatépetl in Mexico produced an ash plume that reached ~8.2 km / 27,000 feet on August 20 and continued to produce steam-and-ash plumes throughout the week following.
Over on the Kamchatka Peninsula, both Koryaksky and Shiveluch produced significant ash plumes (reaching 3-5…
eklemetti | June 30, 2009
Redoubt steaming in early 2009. Image courtesy of Calvin Hall.
It has been a while since we spoke of Redoubt, but now it seems the reason why might be that the eruption is ending. AVO lowered the Alert Level at Redoubt to Yellow from Orange, indicating that they believe the volcano is less likely to have a large eruption. This doesn't mean that it is out of the question, but rather that signs seem to be pointing to the idea that the eruption is waning.
AVO sums the change:
Seismic, satellite, gas, and deformation observations over the past few weeks indicate that growth of the lava dome at…
eklemetti | June 26, 2009
Chaiten in Chile erupting in January 2009. Even after over a year of activity, Eruptions readers are still captivated by the volcano.
Thanks for sending me your questions about volcanoes and volcanism. I'll try to tackle some hear - but as always, keep the questions coming! Send them to
For those of you who have submitted a question but don't see the answer here, do not fret. Likely it just means that I needed to do a little more research into the question and will get to it in a later mailbag!
So, without further ado ...
Mark M.: Here in the Appalachians we have very dense crystalline rock…
eklemetti | June 17, 2009Your weekly dose of volcano news brought you by the Smithsonian Institute GVP and the USGS.
This week's highlights (not counting Sarychev Peak and Turrialba) include:
13,000 foot / 4 km ash plumes from Rinjani in Indonesia. This is part of the continuing eruption there.
The alert level was lowered at Galeras, Colombia to "Orange" after intense eruptions last week.
The current lava dome at Redoubt is 1 km long, 460 m wide, and 200 m high according to the latest images from the Alaskan volcano.
18,000-23,000 foot / 4.8-7.7 km ash plumes from Shiveluch in Kamchatka, along with thermal anomalies…
eklemetti | May 31, 2009
Redoubt steaming away on May 4, 2009. Image courtesy of AVO/USGS
Fairly quiet weekend (except for the start of the College World Series regionals ... I do have a favored team*), volcanically speaking, but the ever-vigilant folks up in Alaska are keeping an eye on Redoubt as the eruption of 2009 continues.
The weekly status (released 5/29) for Redoubt released by AVO has no big surprises, reporting that "small discrete earthquakes and rockfall signals in the summit region have been recorded steadily over the course of the past week. In other words, the dome continues to extrude and part of it…