04 January 2009

Volcano Checkup

YELLOWSTONE still shaking one week after first tremor. The small earthquakes that began in the park a week ago continue. They include three more earthquakes Friday that measured stronger than magnitude 3.0. A quake of magnitude 3.5 happened at 11:30 a.m., followed by quakes measuring 3.2 and 3.1 at 12:40 p.m. and 1:15 p.m. Several hundred quakes centered under the north end of Yellowstone Lake have now occurred since last Friday. The strongest so far was a magnitude 3.9 quake last Saturday.

The USGS discounted chances for cataclysmic eruption of the caldera, noting that the hot, active magma chamber below Yellowstone has turned into "largely crystallized mush." But the same study also said: "Depending on the nature and magnitude of a particular hazardous event and the particular time and season when it might occur, 70,000 to more than 100,000 persons could be affected; the most violent events could affect a broader region or even continent-wide areas." A supervolcano event does not appear to be imminent. "We don't think the amount of magma exists that would create one of these large eruptions of the past...we would expect to see more and larger quakes, deformation and precursory explosions out of the lake. We don't believe that anything strange is happening right now."
Yellowstone Earthquakes Raise Fears

1 comment:

  1. Hey, John. This is me being a fanatic. You should have quit while you were ahead.

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