Seismic Slips, Volcanic Bulges, and Hot Lava
Via Doc Searls Weblog article “Creepy” we hear that the is a “slow seismic slip event” occuring in the Pacific Northwest. More from LiveScience:
The slip began Sept. 3 on the Olympic Peninsula of Washington State and has migrated north to the Vancouver Island area, Cassidy wrote. Victoria moved 0.12 inches (3 millimeters) to the West over the course of two days. The events are thought to last six to 15 days.
Not a lot, to be sure, but it means that the potential for a mega-quake is elevated:
“The probability of occurrence of a megathrust earthquake is about 30 times higher during this approximately two-week window, than during the rest of the 14.5 month cycle,” [geologist John] Cassidy told LiveScience. “Having said that, 30 times a small number is still a small number.”
If that's not enough slow-moving geologic events for you, we also have a volcanic bulge near Bend, Oregon, as reported by the US Geologic Survey (email, 9/13/05):
A large, slow-growing volcanic bulge in western Oregon is attracting the attention of seismologists who say that the rising ground could be the beginnings of a volcano or simply magma shifting underground.
Scientists said that the 100 square-mile bulge, first discovered by satellite, poses no immediate threat to nearby residents.
That bulge is growing 1.4 inches per year.
Since I live 40 miles from Mt. St. Helens, all these tectonic happenings, however slow, are of considerable interest. Alana's favorite books are about volcanoes. Ryan often talks about “hot lava” insisting the adjective is important, since cold, tepid, or even warm lavas are boring.
Josh Poulson
Posted Thursday, Sep 15 2005 09:50 AM