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RE: mass extinctions and technology

At 12:56 PM +1000 9/30/02, Mark Harvey wrote:

You have got to start somewhere. To my knowledge, the organic environmental geochemistry of extinction boundary sediments has never been examined.

The inorganic geochemistry also may have something interesting to say. For example, lead levels in sediments have been elevated since lead mining started in Roman times. I believe they dropped in medieval times, then rose in the industrial age.

-- Jeff Hecht