Saturday, January 10, 2009
This images indicates Yellowstone earthquake from the past week. One of the most intense siesmic "swarms" in the national park's history has been shaking the north end of Yellowstone Lake. Since Dec. 26, 900 quakes, 111 measuring magnitude 2.0 to 3.9, have been recorded. Image by the U.S. Geological Survey.
Seismic Activity at Yellowstone by Greg Laden
You have already heard that there has been increased seismic activity at Yellowstone National Park over the last few days. Since December 26th, there have been several earthquakes a day, some jut over 3.0 magnitude, in the vicinity of the north side of Yellowstone’s lake. This is a seismically active region, but the level of earthquake activity being seen now is much greater than seen in perhaps decades (though the data are still not sufficiently analyzed to make positive comparisons yet).Volcano experts have absolutely no clue as to what this means. A major reason for virtually total uncertainty is that Yellowstone sits on top of a very large caldera of the type that is formed by a so-called “super volcano” and the last super volcano to erupt was a few years (like, 70 or so thousand years) before any seismic or other geological monitoring station were set up anywhere. Indeed, the first really serious data collection at Yellowstone began just over 30 years ago.
Anyway, I’ve got a few resources for you in case you want to explore this further. To begin with, I recommend a look at my earlier post on this matter:
The Yellowstone Problem
As you have surely heard, the Yellowstone Caldera … the place where Old Faithful and the Geyser Basin reside … has been undergoing increased “activity” including some earthquakes and a rising up of the land. Is this a big problem? Should the evacuate? Should those of us living only a few states away start wearing earplugs?
My sister, Elizabeth, publishes a newspaper in the vicinity of Yellowstone and they’ve got a very comprehensive piece on he caldera. In fact, my sister’s nickname is Caldera Girl. So she really knows her Calderas.
Tracking Changes in Yellowstone’s Restless Volcanic System
…Since the 1970s, scientists have tracked rapid uplift and subsidence of the ground and significant changes in hydrothermal features and earthquake activity. In 2001, the Yellowstone Volcano Observatory was created by the U.S. Geological Survey (USGS), the University of Utah, and Yellowstone National Park to strengthen scientists’ ability to track activity that could result in hazardous seismic, hydrothermal, or volcanic events in the region…