subglacial volcanism
eklemetti | July 29, 2010Lots of little pieces of news I've run across ... time to play a little catch up.
Stromboli: A volcano after Don Ho's heart.
Every once in a while, my RSS feeds will dredge up some articles from years gone by ... and this week there were two New York Times pieces that are a few years old, but interesting nevertheless. The first is about research conducted by Dr. Robert Sohn at WHOI on explosive undersea eruptions. The second is work by Corr and Vaughan about finding subglacial volcanism in Antarctica. Both are interesting reads if you missed them (like I did) the first time around.…
eklemetti | July 12, 2010The latest Eruptions Word of the Day is "Tuya".
So, what is a tuya?
This is a tuya:
A tuya! Click on the image to see a larger version. Image by Erik Klemetti.
Alright, well, that doesn't entirely help, does it?
Lets look at the feature the arrow indicates. Some observations:
(1) It is low and broad.
(2) It has a relatively flat top.
(3) It is steep-sided.
(4) If you look real close, you can see crudely columnar jointing in the some of the outcrops near the top.
(5) If you had a piece of it in your hand, you'd know it was a volcano rock (andesite, very rarely you can find bits that are quite…
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
An aerial view of Eyjafjallajökull erupting on May 11, 2010, with the extent of the black ash from the eruption on GÃgjökull clearly evident, along with the cracks in the glacier near the lava flow. Photo from the Icelandic Met Office, by Sigurlaug Hjaltadóttir.
Since this past weekend's disruptions due to Eyjafjallajökull, the air over Europe has cleared and most of the airports in Spain, Portugal and Germany (along with those in Morocco) have reopened. The current ash advisory by the London VAAC looks like it will only effect transatlantic flights and Iceland itself, with the ash cloud…
eklemetti | May 6, 2010Grading grading grading!
A webcam capture of the eruptive plume from Eyjafjallajökull on the morning of May 6, 2010.
News:
A quick update on the Eyjafjallajökull eruption: The volcano has been producing an impressive ash plume over the last day (see image above). The current ash plume is reaching 5.8-6 km height (19-20,000 ft) - and causing some trouble over Ireland and Scotland. However, much of airspace closed yesterday has reopened (for now). You can see two new images of the ash plume over at the NASA Earth Observatory. As for the continued fallout from the ash plume from April,…
eklemetti | May 5, 2010
A shot of the strombolian activity at the vent of Eyjafjallajökull, taken on May 4, 2010. Image courtesy of the Iceland Met Office.
The latest news from the Eyjafjallajökull eruption has the volcano erupting more explosively again (see above), possibly due to an increased influx of water into the vent area - in any case, the ash has become denser (by volume in the air) and the plume is higher (see below) than in the last couple of weeks. The rate of lava flow extrusion has also gone down in the last few days. The latest update from the Iceland Met Office has a lot of details on the current…
eklemetti | May 2, 2010
Webcam capture of Eyjafjallajökull erupting on May 2, 2010. You can see the steam plume on the middle flanks of the volcano - this is likely a lava flow coming from the summit vents.
A brief update on activity at Eyjafjallajökull:
Overnight, the lava flows from Eyjafjallajökull could be seen in the crater of the ice cap - some of the images posted by Eruptions readers are simply stunning. You can clearly see the red glow of the strombolian eruptions at the vent, and the glow of the lava flows as they had down the slope of the volcano. This has brought a lot of new melting to the snow/…
eklemetti | April 14, 2010
The steam and ash plume from the Eyjafjallajökull subglacial eruption that started early morning, April 14, 2010.
Well, after the brief respite when there was speculation Eyjafjallajökull-Fimmvörduháls eruption might be over, we now know what was going on. After the original fissures ceased activity, the magma found a new route to the surface, this time underneath the Eyjafjallajökull glacier. Eruptions readers last night watched as an earthquake swarm arrived underneath the icecap, which prompted Icelandic officials to start evacuating people from the area around the volcano (photo…
eklemetti | March 4, 2010
Eyjafjallajökull, an ice-capped volcano in Iceland that last erupted in 1823.
We talked a few weeks ago of signs that there were increasing signs that an eruption could occur on Iceland - increased seismicity on the Reykjanes Ridge suggested that magma might be on the move. Now, we have two pieces of evidence that we might see activity at Eyjafjallajökull, on the southern side of the island nation.
First off, there is a focus of seismicity under the area of Eyjafjallajökull, with an especially large bump in the last 2 days. Both the number and magnitude of the seismicity has been marching…
eklemetti | February 26, 2010Catching up with some news:
Anatahan erupting in the northern Mariana Islands in 2003.
I ran across this article right before I got sick, but its been popping up around the interwebs (and is pretty interesting). It details a study in Molecular Ecology that suggests that populations of caribou in Canada's Yukon Territory were strongly effected by the White River Tephra. The White River Tephra is supposedly the largest Holocene plinian tephra (from a ash cloud fallout), with two components dating from ~1900 years ago and ~1250 years ago. The vent for the WRT is likely from a vent beneath the…
eklemetti | February 18, 2010
The Icelandic coast of Reykjanes where the Mid-Atlantic Ridge comes above sea level.
A number of Eruptions readers have noticed that seismicity along the Reykjanes Ridge that runs to the southwest of Iceland onto the island has increased over the last few days. Sure enough, checking the Icelandic Met Office page on seismicity on the island finds a lot of earthquakes on the southwest peninsula that is the manifestation of the Mid-Atlantic Ridge hitting the hotspot-related Icelandic landmass. The interaction between the Iceland plume and the Mid-Atlantic Ridge is complex, with a step in the…
eklemetti | October 6, 2009So, the field still stands unblemished, having identified all 8 MVPs, usually within less than 7 tries. Nice job!
Current MVP Standings:
volcanista - 1
Elizabeth - 1
Ralph - 1
gijs - 1
Anne - 1
Cam - 1
gg - 1
The Bobs - 1
MVP #7 was Arenal in Costa Rica. It was initially going to be Rincon de la Vieja, but somehow I mixed up the pictures. I think a lot of you know a lot more about Arenal than I do, but it is one of the most active - and easily visited - volcanoes in the Western Hemisphere.
Eyjafjöll volcanoHekla from the northwest in Iceland, not your MVP #8.
MVP #8 was Eyjafjöll (or…