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after Dawn Stover's table in March 2005 Popular Science:
The Suspect The Theory The Evidence The Proponents The Holes
Asteroid impact A space rock strikes in the tropics, spews debris into the air and triggers lethal climate change Scientists found 250 million year old rocks from Antarctica and China said to contain meteorite fragments Researchers at the University of Rochester, Harvard, and UC Santa Barbara Scientists have yet to find the ultimate smoking gun, a crater
Sudden methane explosion A massive cloud of methane gas abruptly bursts from the ocean, cataclysmic flooding and fires ensue Great Dying fossils show a sudden sharp rise in carbon-12 isotopes, best explained by a methane belch Chemical engineer Gregory Ryskin at Northwestern University The explosion requires an improbable 10,000 gigatons of methane
Slow methane leak Volcanoes of frozen deposits leak methane over thousands of years, depleting oxygen The burrowing reptile Lystrosaurus, adapted for low-oxygen conditions, thrived during this period Researchers at the University of Oregon, the South African Museum, and the University of Washington The leak could not deplete enought oxygen to cause global death, critics say
Hydrogen sulfide stink bomb Lethal levels of hydrogen sulfide, emitted by anaerobic bacteria, are expelled from the ocean into the air Proponents are searching for signs of sulfur bacteria in Japanese sediments dated to the extinction Scientists at Penn State, the University of Colorado, and the University of Tokyo There's no proof that the upper layers of ancient oceans were devoid of oxygen

6 posted on 04/02/2006 2:18:33 PM PDT by SunkenCiv (
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Methane Explosion Warmed The Prehistoric Earth, Possible Again
Greenbelt - Dec 10, 2001
load large graphic in this window
by Debbi McLean
NASA Goddard Space Flight Center
Multimedia Design Studio
In the last 200 years, atmospheric methane has more than doubled due to decomposing organic materials in wetlands and swamps and human aided emissions from gas pipelines, coal mining, increases in irrigation and livestock flatulence.

However, there is another source of methane, formed from decomposing organic matter in ocean sediments, frozen in deposits under the seabed.
Methane from cattle farts is meaningless, unless one is standing nearby. P, you. Decomposing organic matter in ocean sediments may actually be there, but the methane ices are from below, of abiogenic origin, and in huge quantities (50,000 years worth of natural gas at current rates of consumption).
60 posted on 04/03/2006 11:15:22 PM PDT by SunkenCiv (
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This one is loony.
Global Warming Preserved "Mass Kill" Fossils, Study Says
by James Owen
National Geographic News
October 18, 2005
Greg Retallack, geologist at the University of Oregon... says huge releases of carbon dioxide and methane starved the Earth of oxygen, causing mass extinctions over the last 500 million years. He adds that the resulting buildup of billions of dead prehistoric creatures may have acted as a carbon sink, reducing CO2 in the atmosphere and preventing the Earth from becoming as hot and lifeless as Venus... He bases his theory on a compilation of unusually well preserved fossils found around the world, including fish, crustaceans, insects, and other ancient life forms. The fossil record indicates about 40 episodes of exceptional preservation, he says -- episodes that coincide with periods of global warming, when the Earth was low in oxygen... In some mass extinctions, the scientist says, greenhouse gases "ramped up … to intolerable levels of more than ten times the modern level of atmospheric carbon dioxide." Volcanic activity and outbursts of undersea gases are the prime suspects for these periods of lethal pollution.

65 posted on 04/03/2006 11:27:15 PM PDT by SunkenCiv (
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I've read this data before, in Rain of Iron and Ice, and while I'm in favor of a comprehensive detection program, this seems to me to be an example of the third type of lie.
Disraeli / Twain: "there are three kinds of lies: lies, damned lies, and statistics."
Table. Chances of dying from selected causes (USA)
Cause of death Chances
Motor vehicle accident 1 in 100
Homicide 1 in 300
Fire 1 in 800
Firearms accident 1 in 2,500
Electrocution 1 in 5,000
Asteroid/comet impact 1 in 20,000
Passenger aircraft crash 1 in 20,000
Flood 1 in 30,000
Tornado 1 in 60,000
Venomous bite or sting 1 in 100,000
Fireworks accident 1 in 1 million
Food poisoning by botulism 1 in 3 million
Drinking water with EPA limit of tricholoethylene 1 in 10 million
(From C.R. Chapman & D. Morrison, 1994, Nature 367, 33-40.)

67 posted on 04/03/2006 11:33:06 PM PDT by SunkenCiv (
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To: SunkenCiv

Four theoretical causes of the Permian extincion event.

To what extent could the first event have triggered one or more of the other three effects?

156 posted on 11/02/2006 12:48:07 AM PST by gleeaikin
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