Word: mountains
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Dates: during 1990-1999
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...make a mountain out of a mole hill...
After the ash, some volcanoes produce what is known as a pyroclastic flow, a ground-hugging cloud of superheated gas and rock that forces a cushion of air down the mountainside at up to 100 m.p.h., incinerating anything in its path. Other mountains spew that signature substance of the volcano: lava. (On this point Dante's Peak was wide of the scientific mark, concocting a fictitious mountain that produces both substances.) Lava moves at speeds ranging from less than 1 m.p.h. to 60 m.p.h...
Chouet is not the only researcher who's using the orbital high ground to study the volcanic underground. In Alaska, USGS researchers have placed satellite receivers at different points on the sloping side of the Augustine volcano and tuned them also to the gps. Like any volcanic mountain, Augustine is swelling slightly as it fills with magma. The degree of this deformation--as calculated by the gps--can help determine the imminence of the eruption. Elsewhere, scientists are leasing time on European or Japanese satellites to take photos of volcanic peaks as they undergo a seismic event like an earthquake...
...always require such sophisticated instruments. Increasingly, researchers have come to appreciate that volcanoes, like living organisms, have their own internal metabolisms, and like any metabolic system, they give off telltale waste products--particularly gases. Williams is developing a new way to read those gases and predict just when a mountain will probably detonate...
...magma rises in a volcano, light molecules like carbon dioxide bleed off more than heavier gases like sulfur dioxide. The higher the CO[2] levels, the likelier an eruption. If magma gets stuck in the gullet of the mountain, SO[2] predominates. The more SO[2], the more stagnant the magma and the less probable an eruption. The problem is that taking accurate measurements may require climbing almost directly into a volcano--a decidedly dangerous proposition...