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Re: extinction

Response to David Marjanovic's post of Fri, 16 Jan 2004 21:35:34.

David wrote:

 > Volcanic debris can float for long
 > distances via marine currents.

"But certainly not uphill to the purely terrestrial Nanxiong Basin. You'd need a second impact to create the gihugrongous tsunami necessary to wash seawater into that basin, and I _am_ taking paleogeography into account."

Re the K-T transition iridium spikes, are you advocating that the splendid works of Zhao, and other Chinese scientists be disregarded because they do not fit your notions of K-T science?

Incidentally, as regards a K-T climate change, here is what Zhao and Yan had to say about me in their paper, "Stable isotopic studies of dinosaur eggshells from the Nanxiong Basin, South China" (Studies in China, 2000, v. 43, pp. 84-92):

"Therefore, it seems logical to reason that the trend toward more negative C-13 values of the eggshells in the two studied sections could be an indirect consequence of a lasting increase in CO2 concentration in air during the K/T transition. This seems to agree with the model developed by McLean [22-24] who proposed that CO2-induced greenhouse warming was caused by the Deccan Traps volcanism during the K-T transition."

Dewey McLean