Science & Technology at Scientific American.com: Geologists Link the "Great Dying" to Volcanism
A short article in Scientific American (above) makes it perfectly clear just how unfriendly the earth's environment can be (even before nasty people came on the scene to ruin the Garden of Eden.) To quote:
"Roughly 252 million years ago, life on the earth nearly ceased to exist--as much as 90 percent of marine life and 70 percent of terrestrial life died out. At around the same time, a vast up swelling of magma covered between one million and four million cubic kilometers of what is now Siberia. The eruption continued off and on for about a million years, with basalt lava and poisonous gases seeping up through cracks in Siberia's mantle....
The researchers argue that the deadly gases of the Siberian eruption killed vegetation across the globe, just as much smaller modern eruptions have produced acid rain and other plant-killing phenomena. Without roots to hold the soil in place, rivers and streams washed most of the dead vegetation to the sea where it then blocked the sun's light and sucked up all the oxygen. "What began on land ended in the sea," Visscher says. "It seems there was no place to hide at this time of great dying."
And when could it happen again?- Any time now.
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