| 中国冈瓦纳研究的兴起及与板块构造有关的几个关键古生物地理问题 |
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| THE RISE OF GONDWANA RESEARCH IN CHINA AND SOME KEY PROBLEMS ON PALEOBIOGEOGRAPHY RELATED TO PLATE TECTONICS |
| The present paper deals with some key problems of the Palaeozoic and Mesozoic paleobiogeography of China. After having analyzed both new and former data concerned, the author is inclined to a large-scale drift concept in favour of plate tectonic explanation.The Early Palaeozoic faunas of China (including benthic, planktonic and nektonic) are essentially unique in sense of their eco-climatic nature and characterized by high diversity. By this means we can obtain such an understanding that all continental blocks of China in company with other continents of the world were located in the Southern Hemisphere or near the pa-leoequator during the Early Palaeozoic.Since the Late Palaeozoic the faunas and floras of China started to differentiate. The Gondwana biotas and fossil-bearing glacio-marine deposits of the Qinghai-Tibet Plateau indicate it was an indivisible part of the Gond-wanaland. South China with the typical Tethyan fauna and Cathaysian flora had a tropic setting in the Tethys Ocean. North China with transitional biotas of the Permian age had reached the Siberian edge at that time. Considering the fact that the Cathaysian and Gondwana biotas joined together since the Latest Permian or the very beginning of the Triassic, the Changtang-Indochina block, the marginal member of the Gondwana masses, had welded to the Cathaysia at this moment.Judging by the appearance of Triassic Boreal ammonites in Qinling and the final stage of the Jishishan ophiolite section, which fell into the latest Permian to earliest Triassic, both South and North China must have settled up approximately at their recent positions in the Triassic time.Based on the Tethyan character of the Juro-Cretaceous biotas from North Tibet and the Upper Triassic to Jurassic age of the Nujiang-Bangong ophiolite belt, the North Tibet block is thought to have welded to the Eurasian in the Late Jurassic. On the other hand, the Tethys nature of the Juro-Cre-taceous faunas from Himalayas and the Cretaceous age of the Zangbo-Indus ophiolite evidently show that the collision of the South Tibet-Indian block with the Eurasian took place at the end of the Cretaceous. In this way, the Chinese continent of the recent shape had been erected since the Early Tertiary.The magnificent drifting of the continents from the Southern to Northern Hemisphere was a striking phenomenon of the earth's surface at least since the Sinian period. It was certainly induced by a geophysic mechanism in the depths of the Earth and serves an awkward subject in need of elaborate work of the geologists, as noticed by some former geologists (for example Bubnoff, 1954) long before. Although the general trend of drifting is explicit, some important links of it, especially for Precambrian periods, still obscure. |
| WANG Nai-wen.1984.THE RISE OF GONDWANA RESEARCH IN CHINA AND SOME KEY PROBLEMS ON PALEOBIOGEOGRAPHY RELATED TO PLATE TECTONICS[J].Acta Geoscientica Sinica,6(3):103-115. |
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