三叠纪古生物地理与大陆漂移

自板块说问世以来,大陆漂移理论获得了新的生命力,二十年来迅速发展,已经在许多学科领域内获得大量的证据。本文试图从三叠纪古生物地理和地层的角度,对其进行讨论。

TRIASSIC PALAEOBIOGEOGRAPHY AND THE CONTINENTAL DRIFT

This article demonstrates from the viewpoint of palaeobiogeography the inexistence of the Atlantic Ocean, the union of the southern continents into the Gondwanaland, and hence the presence of the Pangaea in Triassic. After giving a short critique on the traditional treatment of the Triassic Tethys in palaeogeographic map, this article discusses the differencs of benthonic organisms between the southern and northern margins of the Tethys, the distribution of abyssal faunas and the direct contacts of utterly different biological-petrographic facies due to subduction of the oceanic crust, all of which stand for the existence of a vast Tethys ocean during Triassic as suggested by the theory of continental drift. A special section is devoted to the Triassic grand triangle occupying parts of Sichuan, Gansu, Qinghai and Xizang (Tibet) of China. Summing up all available data of biostratigraphy, palaeobiogeography and various aspects concerning Triassic drifting, the author concludes that the triangle was a northern part of the Triassic Tethys, while the Xizang-Western Yunnan microcontinent was a Noah’s Ark drifting northeastward and collided and combined with the Eurasian plate in Late Triassic, thus bringing an end to the oceanic development of the triangle.