No. 12: Fall 1980
Cuvier (1769-1832) was a catastrophist. To him, the record of death in the layers of fossiliferous rocks was obviously the consequence of terrestrial convulsions. But Cuvier's ideas were swept aside by the uniformitarians who saw the earth and its cargo of life unfolding with almost agonizing slowness. But Cuvier is making a comeback, as illustrated by the following back-to-back articles in Nature. We quote from the abstracts.
"Closely spaced samples from an uninterupted calcareous pelagic sequence across the Cretaceous-Tertiary boundary reveal that the extinction of planktonic Foraminifera and nannofossils was abrupt without any previous warning in the sedimentary record, and that the moment of extinction was coupled with anomalous trace element enrichments, especially of iridium and osmium. The rarity of these two elements in the crust of the Earth indicates that an extraterrestrial source, such as the impact of a large meteorite may have provided the required amounts of iridium and osmium."
(Smit, J., and Hertogen, J.; "An Extraterrestrial Event at the Cretaceous-Tertiary Boundary," Nature, 285:198, 1980.)
"Evidence is presented indicating that the extinction, at the end of the Cretaceous, of large terrestrial animals was caused by atmospheric heating during a cometary impact and that the extinction of calcareous marine plankton was a consequence of poisoning by cyanide released by the fallen comet and of a catastrophic rise in calcitecompensation depth in the oceans after the detoxification of the cyanide."
(Hsu, Kenneth J.; "Terrestrial Catastrophe Caused by Cometary Impact at the End of Cretaceous," Nature, 285:201, 1980.)
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