volcanic hazards
eklemetti | February 4, 2010News!
Pakistan is home to the world's tallest mud volcano in the region of Balochistan - and its somewhat near the reports of an "eruption" earlier this week.
Guess what? Since Wednesday evening, seismicity at Yellowstone has dropped precipitously. The last batch of earthquakes on February 3rd were also back to deeper levels - 8-9 km depth - compared to the potential shallowing earlier in the week. I'm sure the caldera will keep us on our toes, but as of now, it seems to have settled down a bit.
Over in Pakistan, there is mounting evidence that the recent "volcanic" eruption reported as, in…
eklemetti | February 3, 2010With all the talk of the current Yellowstone earthquake swarm, I thought it would worth it to write a post on the the structure and caldera - and why we get earthquake swarms that are structurally rather than magmatically-related.
First off, lets think about why calderas formed. This is relatively simple - at least superficially. The land (or volcano) above a magmatic system is partially supported by that magma, especially because magma is hot and buoyant. The isostatic support by the magma holds up the land surface or volcanic edifice, so when an eruption expels a large volume of magma, this…
eklemetti | February 3, 2010
Steaming, gurgling mudpots in the active hydrothermal system of Yellowstone.
For those of you following Yellowstone (I think there might be a few of you), I've plotted up the earthquakes since 1/27 (see below) - and sure enough, although there is a lot of scatter, they are getting shallower - however what this exactly means is unclear. You can see my plots from 1/22-28 here. As many of you have mentioned, a caldera like Yellowstone is a big interconnected system, so a solely tectonic source of this is still possible as the displacement migrates through the fractured caldera rocks.
UPDATED…
eklemetti | February 2, 2010
Tungurahua erupting in an undated AP photo (although I think it is the current 2010 activity.)
It hasn't really made it to much of the English-speaking news, but the current eruptive activity at Tungurahua appears to be on the up-tick. Hugo Yepes of the Geophysical Institute of Ecuador suggests that a larger eruption is not out of the question (link in spanish), but right now the activity is confined to explosions (vulcanian?) and ash fall around the region, specifically on Pillates and Choglontus overnight (2/1) from the ~ 2 km / 5 000 foot plume. Looking at the specifics (link in spanish…
eklemetti | February 1, 2010First off, I wanted to thank all of the Eruptions readers for making January the most popular month ever on this blog. I suppose I should give an assist to Yellowstone, but really, thanks for coming to the blog, reading the posts and engaging in all the great discussions that go on within its (cyber)walls.
KÄ«lauea's east rift zone eruption site. Image courtesy of the USGS/HVO.
On to some news!
I suppose you've made the big time when you're in the New York Times, and sure enough, the current Yellowstone earthquake swarm is in the Old Grey Lady. Nothing much new to read, but summarizes the…
eklemetti | January 28, 2010Some news for the last Friday in January:
Volcanic lightning captured over Redoubt in March 2009.
Tungurahua in Ecuador continues to erupt. Yesterday, the volcano spread ash over much of central Ecuador. Apparently people in Ecuador aren't taking the hazard of ash too seriously, with many ignoring recommendations to wear masks when the ash is falling. Over 50 explosions have been recorded over the last 24 hours at the volcano according to the Ecuadorian Instituto GeofÃsico, most of them small to moderate.
We also have a new USGS/Smithsonian Institute Volcano Activity Report. Much of the "…
eklemetti | January 28, 2010
Bezymianny in Kamchatka, one of the many volcanoes in eastern Russia that will no longer be monitored by KVERT.
In some bad news for volcano watchers (and the general public, too), Russia has decided to stop funding KVERT (the Russian equivalent of the Alaska Volcano Observatory), the institute that monitors and researches volcanic eruptions on the Kamchatka Peninsula and the Kuril Islands in the western Pacific. Here is the news release from KVERT:
Due to a loss of government funding beginning February 01, 2010, KVERT will no longer
distribute information regarding volcanic activity in…
eklemetti | January 27, 2010
Old Faithful geyser at Yellowstone National Park.
A few thoughts about faulting, earthquakes and eruptions:
The earthquakes at Yellowstone have been universally attributed to fault movement rather than magmatic activity by the USGS and the researchers at the University of Utah. This is likely based on the moment solutions for the earthquakes (i.e., the sense of motion on the earthquake - side to side, dilation, etc.) and the fact that there are no directly correlative volcanic/magmatic symptoms to go with them (such as pronounced, short-term bulging, excessive hydrothermal venting, etc.) Now…
eklemetti | January 25, 2010Two quick notes:
A Costa Rican farmer evacuating in early January 2010 after renewed activity of Volcan Turrialba.
Well, it appears that after a quiet night on Friday, the current Yellowstone swarm picked up where it left off. We're now up to 1,200 earthquakes since January 17th, with a pair over M3 today. Of course, people are still uppity about the swarm, especially after the earthquake in Haiti, but really, they're about as connected as worrying about the rainy day in Boston when there was a typhoon in Malaysia. Just to get people on the same page, YVO still says: "The swarm events are…
eklemetti | January 21, 2010
Sakurajima in Japan, erupting in December 2009. Image courtesy of Photovolcanica.com
Richard Roscoe at Photovolcanica.com has just posted two great sites focusing on two of the most active volcanoes in Japan: Sakurajima and Suwanosejima. These volcanoes are almost constantly erupting with small strombolian events punctuated by occasional plinian eruptions.
Sakurajima is on the island of Kyushu (well, technically Kagoshima, but right off the coast of Kyushu) less than 10 miles / 20 km from the city of Kagoshima. The volcano has been erupting since 1955 with both explosive and effusive…
eklemetti | January 20, 2010This week's USGS/Smithsonian GVP Volcano Update!
Highlights include:
A volcano I had never heard of in the Kuril islands is showing signs of life: Kharimkotan. Satellite images show a thermal anomaly at the summit of the volcano - its last known eruption was in 1933.
Ash, sulfur dioxide and steam continue to erupt from Nyamuragira in the Congo, although lava flows have abated.
Crater C at Arenal had sporadic strombolian activity - which is par for the course for the Costa Rican volcano.
I must have missed this, but since December 14, the ash erupted at Gaua in Vanuatu has become denser and…
eklemetti | January 20, 2010Quick news updates for a Wednesday...
The island (and volcano) of Gran Canaria in the Atlantic Ocean. It last erupted in ~20 B.C.
The earthquakes keep coming at Yellowstone - up to a M3.5 in the last 24 hours. Time has already put up an article wondering about whether people need worry about the swarm (there might be other things to worry about before this swarm). YVO's statement on the earthquake swarm seems pretty standard (as it should be): "At this time the Yellowstone Volcano Observatory does not consider the swarm to be unusual and the earthquakes are likely related to tectonic fault…
eklemetti | January 14, 2010The weekly volcano report, brought to you by our friends at the Smithsonian Global Volcanism Program and the U.S. Geological Survey.
Highlights (not including Mayon, Nyamuragira and Turrialba):
Eruptions continue at Piton de la Fournaise on Reunion Island - heck, this would be the volcano news if it wasn't for all these other, more explosive systems getting in the way. Lava fountains, flows and pools were the order of the day in the SW Dolomieu crater until the 12th of January.
Chaiten in Chile continues to chug along - block-and-ash flows were seen and ash plumes continue to emanate from…
eklemetti | January 13, 2010Somehow I haven't posted a bunch of interesting items collected over the last few weeks, so I need to catch up. A pre-emptive hat tip to everyone who has sent me links or notes that might seem familiar in this post.
Tungurahua in Ecuador erupting in 2000.
First off, those of you looking for information on the Haitian earthquake that devastated the capitol Port Au Prince, Highly Allochthonous has post on the tectonics of the quake. Right now, it is hard for me to come up with a worse location in terms of devastation for a quake to have hit in the Caribbean Basin.
Back in volcano news, a lot…
eklemetti | January 11, 2010
The streaming crater of Turrialba in an image taken in mid January 2010.
I have a moment to spare here at WMU, so I thought I would pass some of this confusing news along concerning Turrialba. Some of the latest reports refer to a "crack" in the crater of the volcano ... specifically:
Geologists and volcanologists were at least able to confirm that the crack on the wall of the volcano is getting larger, confirmed by flybys by helicopters during a break in the weather. The experts say the constant spewing of gases is causing the crack to get bigger and could collapse the volcano's crater wall…
eklemetti | January 8, 2010The weekend! No updates until next Tuesday - I'll be off to give a talk at Western Michigan University.
Coal-erupting volcanoes defeat the Permian dinosaurs ... according to FOX News.
Anyway...
You know that mainstream media (FOXNews) must have done something appalling when even I can't write about it thanks to my seething rage. I'll let Chris Rowan at Highly Allochthonous and Ralph at the Volcanism Blog sum up how FOX News tried to explain the extinction of the dinosaurs (hint 1: it happened before dinosaurs even existed. hint 2: volcanoes erupt coal now).
After you've read about that…
eklemetti | January 7, 2010
The steam plume from Turrialba on December 26, 2009. Image by Eruptions reader Sahrye Cohen.
Turrialba
Costa Rican officials extended the evacuation zone around Turrialba from 3 to 6 km, raising the alert status at the volcano to Yellow. Vanessa Rosales of the National Emergency Commission described the seismicity as "intense but low," but says the country is prepared to deal with the emergency. As always, the news chooses oddly what is the "news" of an event, and many article on Turrialba focus on Costa Rica's coffee - yes, it is safe, so far. A news report from the Tico Times quotes Raul…
eklemetti | January 6, 2010Two volcanoes down, two volcanoes up!
Fire fountain on Nyamuragira in the Congo, January 2010.
Down
Mayon
Activity at Mayon has continues to drop - although PHIVOLCS warns that an eruption could happen at any moment and without much warning. About a quarter of the evacuated families have no returned home since PHIVOLCS gave the OK to return home on January 2 - but Philippine officials are still on alert in case evacuations have to be reinstated.
Redoubt
The resurgent Redoubt is no long ... er ... resurging? AVO lowered the alert status to Green - meaning normal/background levels of activity…
eklemetti | January 5, 2010Yet another new eruption for 2010!
Turrialba volcano in Costa Rica in an undated photo.
Turrialba in Costa Rica erupted today, prompting the evacuation of tens of people from the region near the volcano. The eruption appears to be relatively small, producing ash and some pyroclastic material. The area around the volcano is not very populated and isn't near the profitable coffee-growing region of Costa Rica. This eruption is the first at Turrialba since 1866, over 130 years ago. That eruption was a VEI 3, so Turrialba is definitely a volcano to watch if the activity continues.
Also in Costa…
eklemetti | January 3, 2010A pile of news for the new week!
The glow of new lava flows from Nyamuragira in the Congo, taken from the Virunga Park Headquarters, January 2, 2010.
Mayon
PHIVOLCS may lower the alert status at Mayon to Level 2 after almost a week of lower seismicity and no ash explosions since December 29th. Schools that were being used as evacuation centers were also returned to teachers and students for the start of classes after the Christmas holiday. However, the Albay provincial government is now considering a plan to permanently move everyone who lives within the 6-km danger zone around Mayon, even…