Word: permian
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...team of U.S. and Chinese researchers studying the remains of volcanoes that began erupting 250 million years ago reported that according to radioactive dating, the eruptions coincided in geologic time with one of the great unexplained cataclysms in earth's history--a mass extinction at the end of the Permian period that wiped out up to 95% of all ocean-dwelling species and at least 70% of land-dwelling vertebrates...
What could have caused such indiscriminate carnage? Marauding comets, exploding stars, greenhouse warming, ice-age cooling, sea-level drops, sea-level rises, ocean stagnation, oxygen depletion--every calamity imaginable has been invoked to explain the Permian extinction. But none of these agents of doom, argues geologist Paul Renne, director of the Berkeley Geochron ol ogy Center in California (and lead author of the Science article), comes as close to explaining what happened at the end of the Permian as the rampant, prolonged volcanism that created the terrace-like formations known as the Siberian Traps...
...problem with these theories, observed scientists attending a workshop on the Permian extinction held by the Smithsonian Institution last week, is that they are still highly speculative. For instance, the geological record clearly shows that a staggering drop in sea level-perhaps as much as 300 ft.--did in fact occur during the Permian. But there is no evidence that global cooling triggered by volcanism was the cause. Similarly, new analyses of late Permian soils suggest that a substantial surge of acid rain accompanied the extinction. Acid rain, however, does not require a volcanic source. It could also have been...
...Smithsonian paleobiologist Douglas Erwin warned his colleagues last week, it is dangerous to try to explain a complex calamity like the Permian extinction in simplistic terms. The Great Dying, Erwin believes, was produced by an interplay of many forces--"a tangled web rather than a single mechanism"--and if paleontologists and geologists want to sort out the puzzle, they must spend long hours in the field searching for further clues. Even after scientists reach a consensus about what caused the extinction, observes Renne, a central mystery will remain. What is it about life, he marvels, that enables it to rebound...
...wind-beaten, mesquite-covered, dust-ridden, sun-baked locale that novelist Larry McMurtry calls (in Texasville) "the worst town on earth." Odessans often fill every one of the 20,000 seats in the gleaming $6 million stadium, complete with two-story press box, built in 1982 for Permian High School's five-time state champions, the Panthers. Odessa's preoccupation with the Panthers is richly chronicled in Friday Night Lights, by H.G. Bissinger. Example: Permian High School budgets less for English department materials ($5,400) than for rush film prints of its football games ($6,400). Bissinger's book...