shield volcano
eklemetti | July 20, 2008
I'm back from my conference and will hopefully be getting back to a regular schedule!Â
In the meantime, the biggest news is still the eruption of Okmok Caldera in Alaska. The latest news has the eruption still going strong and the USGS predicting it will continues for potentially weeks to months. The eruption is apparently from a new vent on the caldera floor as well. Looks like the current eruption might be a VEI 4 (or thereabouts) eruption based on what I've heard from USGS scientists.Â
The largest hazard posed by Okmok right now is to air travel, this during a time when the Alaska…
eklemetti | July 15, 2008Here's a stunning shot of the current eruption at Okmok Caldera in Alaska (brought to us by National Geographic).
Personally, I think the best part is the fact that this was shot by an Alaska Airlines pilot! Talk about "to the right of the plane..." fodder.
eklemetti | July 14, 2008Sorry about the brevity of this update, but I'm exhausted.
From the Alaska Volcano Observatory (AVO):
At this time, based on AVO analysis of satellite data, ash is
continuing to erupt from a composite cinder and spatter cone called
Cone D in the eastern portion of the 6-mile wide caldera or crater of
Okmok. It appears that the eruption is very water-rich due to
interaction of rising magma with very shallow groundwater and
surficial water inside the caldera. We have few direct observations
into the caldera and details of the current event remain unknown.
The current activity differs in…
eklemetti | July 13, 2008
Sorry about the delay with updates, I am actually at a meeting filled with volcanologists (of all things), so updates might be a little sporadic.
A lot of news today about Okmok erupting in the Aleutians. The Alaska Volcano Observatory had this to say:
The eruption at Okmok continues based on high levels of seismicity and ash continues to be erupted as indicated in satellite observations. Seismicity reached a peak at about 2200 Z
(2:00 PM ADT) yesterday and has been gradually declining since. Reports from Unalaska indicate no ash fall in Unalaska/Dutch Harbor since last night. However,…
eklemetti | July 12, 2008
Okmok Caldera in Alaska's Aleutian Islands erupted today, sending an ash column to at least 30,000 feet. Very little news has been released about the eruption so far beyond this information about the eruption column and some bits about precursor seismicity. A number of flights to Unalaska Island were cancelled due to the eruption. I'll pass on more information when I get it.
Okmok is located near Dutch Harbor, Alaska and is a large shield volcano with two prominent calderas at the top. In fact, whenever I see pictures of the caldera, I am reminded of what Crater Lake (Oregon) might look…
eklemetti | July 8, 2008Â
Kilauea is busy keeping geologists and tourists alike wondering what the volcano will be doing next. The current report on the volcano tells of a new fire fountain at the Thanksgiving Eve Break-out "rootless cone", about 6 miles from the ocean. The fire fountain started on Sunday night, issuing lava up to 40 feet in the air and the USGS has posted an amazing video of the fountaining on the HVO website. However, unlike the predicted behavior where magma at Kilauea starts near the summit and moves into the rifts, these lavas appear to be unrelated to the activity going on at the summit of…
eklemetti | July 5, 2008
There are some nice videos of the current eruption of Kilauea (after some tedious commercials via the link at the top of the article) with lava spattering and lava reaching the sea on the 4th of July. Not much description of the eruption in the article, but it sounds like it is just the Hawai'ian volcano doing what it does best (and possible ramping up for more).
eklemetti | June 20, 2008
Not much in the way of science to add here, but photographers at Hawai'i Volcanoes National Park are still busy around the clock documenting the summit vent activity at Kilauea that started in March. Most of the activity is steam escaping from the vent, but at night, the vent glows red, proving just how close to the surface the magma is right now. Occasionally, the volcano throws out some volcanic clasts, probably in phreatomagmatic (water/magma interaction) explosions. The USGS Hawaii Volcano Observatory has a nice series of photos of the current activity and research as well, mostly…
eklemetti | June 19, 2008
The western Pacific basin is pockmarked with active and extinct volcanoes related to the subduction of the Pacific plate along almost all of its western boundary. An Australian National University research group recently discovered a pair of undersea volcanoes that would put any good mining geologist into a fit of joy. These volcanoes are spewing volcanic gases underwater that are very rich in metals like copper, lead, zinc and gold. All of these metals like to go into solution in acidic fluids like volcanic gases, and when these volcanic fluids meet the cold (and decidedly less acidic)…
eklemetti | June 6, 2008
I had been looking for some pictures of the recent eruption of Cerro Azul in the Galapagos, and finally I found some posted on the BBC. There are some rather stunning pictures of the rift eruption (#3), the lava flows heading downslope (over older lava flows, #4) and even a little lava spatter (#1).Â
eklemetti | June 3, 2008
The latest reports from Cerro Azul in the Galapagos indicate that the current eruption that started last week is over. The volcano erupted from Thursday to Sunday and produced lava flows that travelled 10 km from the vent, but little damage was reported. It is hard to tell from the report if this is the believed to represent all the activity to be expected at Cerro Azul, but more likely than not we'll see more eruptions if this is a new stage of activity at the volcano (in spanish).
eklemetti | May 30, 2008
I always find it interesting how and why news of a volcanic eruption makes it into the press. Sometimes it is just to report the eruption itself, however, a lot of the time it is more to report the "human interest" side of the story, or in this case, the wildlife side of the story. Cerro Azul, one of the volcanoes in the Galapagos islands, apparently erupted on Thursday (5/29). Lavas flows on the northeast side of the volcano are threatening the Giant Galapagos Tortoises and their status (the tortoises and the lava flows) will be monitored.
On the volcanic side of things, Cerro Azul last…
eklemetti | May 5, 2008
For those of you who have missed it, Halemaumau Crater at Kilauea (Hawai'i, USA) have been experiencing new eruptions - some of them explosive - for the last couple months. These are the first eruptions at Halemaumau since the 1980s and the first explosive eruptions at Kilauea since the 1920s. Much of the area around the crater in Hawai'i Volcanoes National Park are closed due to the volcanic gases and the potential for more explosive eruptions to throw material out of the crater. These explosive eruptions are likely caused by the interaction between the magma below the surface intersecting…