St. Helens
eklemetti | July 4, 2010So, I've had requests on the blog to help to do some defining of volcanologic terms on the blog, so I thought I'd try a new column called Eruptions Word of the Day. I'm not sure how often it will run, but let's give it a try.
Eruptions Word of the Day for July 5, 2010: Dacite
Dacite is a magma type defined by silica (SiO2) content between 63-68 (or 69) weight percent. That is the textbook definition, but some other typical characteristics of dacite lavas (or magmas) is the presence of certain minerals: plagioclase feldspar and hydrous minerals (containing water in their mineral structure)…
eklemetti | May 18, 2010News, news, news!
Ash from Eyjafjallajökull piling up on a roof at Seljavellir. Image courtesy of the IMO, by Ari Tryggvason.
The latest from Eyjafjallajökull has the volcano continuing to puff away - producing intermittent airspace closures over Europe. The Icelandic Met Office reports a ~7 km (21,000 foot) ash plume, but they note that the explosivity of the eruption seems to have waned some since a maximum on May 13. Right now, the IMO estimates the eruption rate at ~200 tonnes/second. Lets put that in a little perspective - a Ford F-150 pickup weighs about 2 tonnes, so the volcano is…
eklemetti | May 18, 2010Part 2 of your recollections of the May 18, 1980 eruption of Mount St. Helens.
You can read Part 1 here.
You can also check out an amazing set of satellite images spanning 1979-2010 at the NASA Earth Observatory. Great stuff!
-------------------------------------------------------------------------------------------------
Eruption plume from Mount St. Helens on May 18, 1980. Image courtesy of the USGS/CVO.
Peter Carlton
My sister and I were playing in our backyard in West Seattle when we heard the boom. I was 6 years old. I remember lots of phone calls with our relatives in Yakima, watching…
eklemetti | May 17, 2010Some news for a sleepy Monday:
Mt. Hood in Oregon.
The ash from Eyjafjallajökull is, once again, causing significant airspace closure over northern Europe - close of 1,000 flights today. However, much of the closures are fairly short-lived, but that isn't keeping people happy. The eruption hasn't actually changed much, just that the winds are bringing ash towards Europe. The ash for the next few days will likely effect the England, Scotland, Ireland, Netherlands, France and possibly other parts of northern Europe (along with airspace over Greenland and the north Atlantic). The ash plume is…
eklemetti | May 17, 2010May 18, 2010 marks the 30th anniversary of the dramatic eruption of Mount St. Helens in Washington state. Now, rather than recount the event when the USGS and the Cascade Volcano Observatory have done such an excellent job, I turn it over to all the Eruptions readers and their memories of the eruption.
Now, as I've mentioned, I was all of three years old when St. Helens erupted in 1980, so I have no distinct memories of the eruption. My mother has mentioned that she watched the TV coverage with me and my sister, who had been born a two months earlier. However, the real memories of St. Helens…
eklemetti | May 14, 2010Time to play a little catch up ...
Eyjafjallajökull erupting in early May. Image by and courtesy of Martin Rietze.
A brief update on our friend Eyjafjallajökull - the eruption plume from the volcano was considerably taller yesterday, reaching 6-9 km (20,000-30,000 feet), but prevailing winds meant the ash hazard was confined to areas in the middle of the North Atlantic and northern parts of the British Isles. However, even as the ash hazard for Europe wanes (for now), you shouldn't forget the amount of ash being dumped on parts of Iceland. If you want to see some stunning images of the…
eklemetti | May 13, 2010
Mount St. Helens erupting in 1980.
Just a reminder ... please send them to me by May 15 so I can get them all ready for the post on the 18th!
As many of you might (or might not) now, we're heading towards the 30th anniversary of the dramatic eruption of Mount St. Helens in Washington state. Now, I could fill a book with the information out there on the volcano and the eruption, but instead, I think it would be more interesting to get your takes on the eruption. I have to admit, I was all of three when the eruption occurred, so my memories of the event are hazy at best, but if you have any…
eklemetti | May 3, 2010
Mt. Saint Helens erupting in 2004.
I had a chance to watch a new NOVA special that airs May 5 (PBS) on the 1980-1986 and 2004-2008 eruption cycles at Mt. Saint Helens, along with the recovery of the blast zone from the 1980 eruption. It is a fitting episode as we approach the 30th anniversary of the eruption that took out the north side of the volcano and devastated a vast swath of Cascade wilderness in Washington on May 18, 1980. Many of you have already sent me your Mt. Saint Helens memories (keep them coming!) for my tribute to the eruption, but if you want to get started on remembering…
eklemetti | April 30, 2010
Mt. Saint Helens erupting in 1980.
As many of you might (or might not) now, we're heading towards the 30th anniversary of the dramatic eruption of Mt. Saint Helens in Washington state. Now, I could fill a book with the information out there on the volcano and the eruption, but instead, I think it would be more interesting to get your takes on the eruption. I have to admit, I was all of three when the eruption occurred, so my memories of the event are hazy at best, but if you have any memories, reactions or thoughts you want to share on the events leading up to the eruption, the eruption…
eklemetti | April 30, 2010News!
Colima in Mexico erupting in 2008.
The current activity at Eyjafjallajökull is more-or-less unchanged, with strombolian activity producing a 3-4 km tall ash-and-steam plume and the lava flows at the crater moving northward towards the GÃgjökull glacier. You can check out an extensive page on the state of this eruption at the Nordic Volcanological Center - along with a new page with thermal and LIDAR information on the eruption from France.
The Icelandic Met Office notes that the lava has been producing meltwater from the glacier - which many Eruptions readers have noticed as floods…
eklemetti | April 16, 2010Hard to believe, but there is other volcano-related news in the world ...
So, with all deference to Eyjafjallajokull, here it is:
Dome collapse on Colima in Mexico, image taken March 30, 2010.
The new Smithsonian/USGS GVP Weekly Volcano Activity Report was issued, with news about increasing signs of activity at Egon in Indonesia, a possible plume at Miyakejima in Japan and more dome growth at Soufriere Hills.
A study on the economic effect of a new Vesuvius eruption was released and the finding show the potential for a staggering $24 billion of economic damage directly related to an…
eklemetti | March 2, 2010Some news for a busy Tuesday:
The crater at Poas volcano in Costa Rica, taken February 25, 2010. Image courtesy of OVSICORI by Federico Chavarria.
After the MSNBC debacle, it is nice to see some good articles on why the Chilean earthquake was overall less disastrous than the Haitian earthquake, why the tsunami wasn't as large as predicted and why these earthquakes are not abnormal. There are a lot of factors involved - the location, depth, preparedness, wealth - so the comparison can be very telling in terms of both geologic and societal issues.
The other scientific fallout from the Chilean…
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 | October 25, 2009
The southern Washington (and northern Oregon) Cascades, with Hood (foreground), St. Helens and Adams (middle) and Rainier (background).
Remember a few months ago when an abstract from a meeting got people are ruffled because the study said there was a "giant magma chamber" feeding all three of St. Helens, Adams and Rainier in the Cascades? Well, Nature Geosciences has been kind enough to publish the work (the article) and yes, yet again, we can say it is still most likely not true at all.
Graham Hill and others claim that their magnetotelluric work in the Cascades show that a vast magma…
eklemetti | September 23, 2009Some brief tidbits for your Wednesday:
The view of Mt. Saint Helens from the Johnston Ridge Observatory.
There is a decent article about research being done at a dissected caldera system in the Italian Alps' Sesia Valley. The caldera in question is the Permian in age (248-298 million years old) so don't expect to find it in the GVP database, but the outcrops of this ancient caldera are especially well exposed, allowing for a cross section of volcano and plutonic rocks across 25 km of crustal depth (all of which is now at the surface thanks to hundreds of millions years of tectonics). It…
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 14, 2009
Mt. Saint Helens in Washington state, USA
I'm back from my sojourn to New England and its time to play catch up. First things first!
There has been a lot of chatter in my inbox and on the comments here at Eruptions about the study/press release from Graham Hill's research group talking about the potential for a supervolcano forming at Mt. Saint Helens. This study (presented at the AGU Spring Meeting) was based on a magnetotelluric study of the area around (and below) Saint Helens. For those of you unfamiliar with magnetotellurics, it uses instruments that measure the magnetism and electrical…
eklemetti | May 22, 2009
Pohutu Geyser in Rotorua, New Zealand. Image taken by Erik Klemetti in January 2009.
It has been busy busy week for me, capped off today with a talk about my field work in New Zealand (see above), so I don't have much to say. Not much new news today about the Saudi Arabian earthquake swarms, but again, I'll keep my eyes pealed (incidentally, I still haven't been able to figure out why no western news sources have even mentioned the swarm).
Anyway, here's are some volcanic tidbits to enjoy over the long weekend:
Vog, as seen from space. Volcanic fog, fashionably shortened to "vog" is a real…
eklemetti | May 17, 2009
Mount Saint Helens less than 30 seconds after a sector collapse that triggered one of the largest eruptions in the Cascades in the last 500 years.
Today is the 29th anniversary of the dramatic eruption of Mount Saint Helens in Washington state. The eruption dramatically changed the landscape around the volcano along with greatly increasing our understanding of volcanic sector collapses and explosive eruptions. I was going to write a larger entry on the event, but alas, I will instead be lecturing to 100 UC Davis students about the event today instead (sorry folks!)
Instead, if you want to…
eklemetti | April 3, 2009
Image courtesy of USGS/CVO, taken March 8, 2005 from the Cascades Volcano Observatory, Vancouver, WA
For those of you looking for something to relax with and read this weekend, you could wander over to the USGS website and download yourself a copy (for free and legally) of "A Volcano Rekindled: the Renewed Eruption of Mount St. Helens, 2004-2006" (USGS Professional Paper 1750). The report comes in at a mere 872 pages (that's 697 MB download for the whole report), but you can download the pieces that interest you most as well instead of the whole shebang.
Now, I haven't read the whole thing,…