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Extinction of the dinosaurs: A 1982 understanding

Schopf, Thomas J. M. (1982) Extinction of the dinosaurs: A 1982 understanding. In: Geological Implications of Impacts of Large Asteroids and Comets on the Earth. Special papers (Geological Society of America). No.190. Geological Society of America , Boulder, CO, pp. 415-422.

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The objective record appears to be that the dinosaur fauna of the latest Maastrichtian (i.e., latest Cretaceous) was chiefly (and perhaps exclusively) restricted to the Western Interior Seaway of the United States and southern Canada and included fewer than 20 species distributed among approximately 15 genera and 10 families. In the late Maastrichtian, as has been known for many years, sea level went down by 150 to 200 m in the western interior. The interior seaway (along which the dinosaurs were living) dried up and seasonality increased and habitable area was reduced as widespread flood plains yielded to uplifted, restricted basins. This occurrence of a gradually changing ecology correlated with animal extinction conforms to the observed pattern characteristic of many other times in the fossil record. If this pattern applies to dinosaurs as well, then the extinction of the dinosaurs is neither necessarily nor reasonably attributable to any extraterrestrial event. In addition, it appears that the magnitude of the extinction is greatly over estimated because a very small number of species and genera were actually responsible for the familial extinctions.

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Additional Information:© 1982 Geological Society of America. Accepted 22 June 1982. For advice, information, and literature or other assistance over the past two years, I am grateful to J. H. Ostrom, W. P. Coombs, J. D. Archibald, W. Langston, J. Damuth, P. M. Galton, R. M. West, P. Dodson, J. Horner, W. A. Clemens, A. J. de Ricqles, Z. Kielan-Jaworowska, L. J. Hickey, A. Meijer, R. H. Tschudy, and D. M. Raup; and to A. Dhondt for information on European data, and to J. A. Hopson who, from the beginning of this study to its end, has kept me from making more serious errors than those which remain.
Series Name:Special papers (Geological Society of America)
Issue or Number:190
Record Number:CaltechAUTHORS:20150327-104703758
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Official Citation:The Cretaceous/Tertiary Boundary Event - B. The Biological Record: Thomas J. M. Schopf Extinction of the dinosaurs: A 1982 understanding Geological Society of America Special Papers, 1982, 190, p. 415-422, doi:10.1130/SPE190-p415
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:56180
Deposited By: Tony Diaz
Deposited On:27 Mar 2015 19:10
Last Modified:10 Nov 2021 20:55

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