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:
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.