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In response to
"(if I'm remembering my figures correctly...) -- nm"
by
znufrii
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But at this hot spot's current position under Yellowstone there have been three massive eruptions: 2.1 million, 1.3 million and 640,000 years ago.
Posted by
mara
Dec 16 '09, 11:43
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While those eruptions have been spaced roughly 800,000 and 660,000 years apart, three events are not enough statistically to declare this an eruption pattern, explains Smith.
Though Yellowstone could erupt again someday, there is no evidence that the caldera is readying for another massive blast, says Smith. That outlook is shared by Jake Lowenstern, the U.S. Geological Survey's lead geologist at the Yellowstone Volcano Observatory.
Volcanologists with the U.S. Geological Survey believe that supervolcanoes are likely to give decades � even centuries � of warning signs before they erupt. The scientists think those signs would include lots of earthquakes, massive bulging of the land, an increase in small eruptions, "swarms" of earthquakes in specific areas, changes in the chemical composition of lavas from smaller eruptions, changes in gasses escaping the ground and, possibly, large-scale cracking of the land.
None of those indicators are present at Yellowstone, says Smith.
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