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Re: An extinction contributer?

Richard W Travsky <rtravsky@uwyo.edu> wrote
>The October 23rd issue of Science News carried an interesting little
>report on an event dated 55 mya.
>An ocean sediment study turned up a "global burp" (as the article
>title put it) of "billions of tons of carbon-rich gas". This had
>the effect of further warming up an already warm climate.
>This would appear to have some testable components. For
>example, would sediments from that time period show
>evidence of gas release?

A carbon-12 spike was found at that period. Methane hydrate release is
supposedly the only possible mechanism for such a massive release of
lighter carbon isotope. The whole work was based on some mathematical
model. It was assumed that the quantity of oceanic methane hydrate in the
Palaeocene was similar to the present time - some 15 trillion tons. A release
of 8% of this - over a trillion tons - would have been sufficient to cause the
greenhouse effect.

For more detailed discussion see

Kerr R A, Did a blast of sea-floor gas usher in a new age? , Science 1997;
275: 1267

Gautam Majumdar                 gautam@majumdar.demon.co.uk