I knew that the minute I said I'd be back to a "regular" posting schedule that I would fail miserably, so maybe the less said, the better.
Cerro Galan caldera in Argentina (taken from space).
Thanks to all the readers who have been avidly discussing a number of fascinating topics over the weekend.
I have seen/read a little bit about the tectonic-forcing mechanism idea for some caldera-style eruptions. The biggest thing to keep in mind is that the caldera-forming event - that is to say the collapse of the roof into the chamber - isn't usually the "trigger" as much as a result of a large eruption that is already occurring. The roof collapse just finishes the job that has already started - I guess you could imagine it as hitting the afterburners of an already "lit" eruption. However, the question of the connection between the tectonic setting and eruptive activity is fascinating. You just have to be careful not to compare apples (Andean calderas) and oranges (Yellowstone) - although they're both calderas, they are results of very different magmatic processes and tectonic settings.
As for Lazufre, I know that there has been some earlier articles (such as Pritchard and Simon, 2002 in Nature) that suggested that many of the Andean volcanoes are inflating and deflating regularly - the question here is whether this is all "normal" volcano behavior or just the result of us (humans) being able to notice this type of information for the first time. INSAR imaging on volcanoes has only really been utilized over the last 10-15 years.Some news:
- As many of you pointed out, there has been a lot of articles on the distribution of stimulus money to the various USGS volcano observatories. HVO, CVO, YVO, AVO and even the Northern Marianas will get new equipment to replace the aging infrastructure.
The breakdown looks like this:
- $950,000 for the Yellowstone Volcano Observatory
- $7.56 million for the Alaska Volcano Observatory
- $2.4 million for the Cascades Volcano Observatory in Washington state
- $3.3 million for the Hawaiian Volcano Observatory
- $200,000 for the Long Valley Observatory in California
- $800,000 for upgrading networks in the CNMI - northern Marianas
- There has also been a lot of press on the so-called "spiders" being installed at Mt. Saint Helens to monitor activity. I covered this briefly back in May, but I'm glad to see that people might be interested in volcano monitoring.
- We have some details on the changes at Kasatochi in the Aleutians. As I mentioned a few weeks ago, an expedition was set to visit the island for the first time since last summer's eruption. They will be heading out there this week with a reporter from the Anchorage Daily News and he notes that Kasatochi increased in size 32% thanks to the deposits from the eruption - how long that added material will last with the ocean fighting to take that space back is another question. I do love the sort of dry wit scientists partake in, such as this gem from the ADN article:
In a science report in which they wrapped up their 2008 field season, biologists Ray Buchheit and Chris Ford wrote, under a section titled Interesting Observations, "Our island blew up."
Indeed it did!
It will be fascinating to see what else they discover on the island that went from being a home for 200,000 auklets to a barren ash wasteland.