First off, here’s the webcam from Old Faithful in Yellowstone. You’ll want to check back.
As I have noted in a couple of previous posts here and here, I am happily lost in Bill Bryson’s A Short History Of Nearly Everything. (I am listening to the book, but the special illustrated edition is well worth having on the table in the living room too.)
Though I have moved on to Chapter Five, “Life Itself,” I spent a few arresting hours listening to the horrors of geological whimsy this past weekend, learning along the way that the Mt. St. Helens explosion in 1980 had the force of 500 Hiroshima atomic bombs, and that the last time the magma chamber under Yellowstone erupted it did so with 1,000 times the fury of Mt. St. Helens. Then this on recent work in Yellowstone:
[In 1973] geologists did a hasty survey and discovered that a large area of the park had developed an ominous bulge. This was lifting up one end of the lake and causing the water to run out at the other, as would happen if you lifted one side of a child’s paddling pool. By 1984, the whole central region of the park –over 100 square kilometers– was more than a metre higher than it had been in 1924, when the park was last formally surveyed. Then, in 1985, the cnetral part of the park subsided by 20 centimetres (about 8 inches). It now seems to be swelling again.
The geologists realized that only one thing could cause this–a restless magma chamber. Yellowstone wasn’t the site of an ancient supervolcano; it was the site of an active one. It was also at about this timethat they were able to work out that the cycle of Yellowstone’s eruptions averaged one massive blow every 600,000 years. The last one was 630,000 years ago. Yellowstone, it appears, is due.
Just checked. Yellowstone is still there. Has Al Gore included the Yellowstone big blow in his calculations?
UPDATE: Perhaps Laurie David will bankroll my documentary about the perils Yellowstone presents us all? “An Inconvenient Magma Chamber?”
UPDATE: “An Inconvenient Caldera?” As of December ’06 it was rising again. Changing your lightbulbs won’t help with this one. I return to my first observation about Bryson’s book: If it was used to open the first couple of months of 9th grade science, you’d have a lot more kids interested in the physical sciences after the eight weeks or so it took to listen to or read it. BTW: Here’s one graphic –not from the book– that would of course catch the attention of a 14 year old boy: