 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
Methane Thought To Be Responsible For Mass Extinction
Evanston - Sep 01, 2003 What caused the worst mass extinction in Earth's history 251 million years ago? An asteroid or comet colliding with Earth? A greenhouse effect? Volcanic eruptions in Siberia? Or an entirely different culprit? A Northwestern University chemical engineer believes the culprit may be an enormous explosion of methane (natural gas) erupting from the ocean depths. In an article published in the September issue of Geology, Gregory Ryskin, associate professor of chemical engineering, suggests that huge combustible clouds produced by methane gas trapped in stagnant bodies of water and suddenly released could have killed off the majority of marine life and land animals and plants at the end of the Permian era -- long before dinosaurs lived and died. The mechanism also might explain other extinctions and climate perturbations (ice ages) and even the Biblical flood, as well as be the cause of future catastrophes. Ryskin calculated that some 10,000 gigatons of dissolved methane could have accumulated in water near the ocean floor under high pressure. If released quickly, perhaps triggered by an earthquake, the resulting cloud of methane would have an explosive force about 10,000 times greater than the world's entire stockpile of nuclear weapons. The huge conflagrations plus flooding and overturned oceans would cause the extinctions. (Approximately 95 percent of marine species and 70 percent of land species were lost.) "That amount of energy is absolutely staggering," said Ryskin. "As soon as one accepts this mechanism, it becomes clear that if it happened once it could happen again. I have little doubt there will be another methane-driven eruption -- though not on the same scale as 251 million years ago -- unless humans intervene." Community Email This Article Comment On This Article Related Links Northwestern University SpaceDaily Search SpaceDaily Subscribe To SpaceDaily Express Explore The Early Earth at TerraDaily.com
Researchers Discover Half-Billion Year-Old Fossils
Blacksburg, VA (SPX) Jul 12, 2005Scientists interested in ancient life have a wealth of fossils and impressions frozen in rocks that they can study from as far back as 540 million years ago when animals with shells and bones began to become plentiful. But evidence of complex life older than 540 million years is scant and difficult to study. |
|
|
| The content herein, unless otherwise known to be public domain, are Copyright 1995-2006 - SpaceDaily.AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA PortalReports are copyright European Space Agency. All NASA sourced material is public domain. Additionalcopyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement |
