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中特提斯是中生代中晚期存在于南、北大陆之间的海洋。该海洋在晚白垩世消亡后 ,遗留长千余公里的班公湖 怒江板块结合带。在大量研究成果中 ,对中特提斯如何消亡这一重大问题至今分歧甚大。不少研究者持洋壳俯冲消亡 (东太平洋模式 )观点 ,但在俯冲方向上却有向南或向北之别。笔者则认为中特提斯是一个具有众多互不相通、时代早晚不同的狭窄洋盆的特殊海洋 ,其消亡过程中根本未发生过大规模的洋壳俯冲 ,故提出剪式闭合加地体逐次拼贴的盆内聚敛消亡模式 ,即中特提斯的消亡由早侏罗世晚期羌塘 三江板块与冈底斯 念青唐古拉板块及其中的嘉玉桥 怒山地体 ,首先在东段无俯冲汇聚开始 ,中、西段此时基本上仍处于扩张状态 ,地体裂离与新的狭窄小洋盆产生同时进行 ,中特提斯呈东闭西张的剪刀状。中晚侏罗世 ,中西段北侧出现构造地体往羌塘 三江板块拼贴与南部地体裂离出新地体的复杂局面。至早白垩世末 ,新老地体拼贴、裂离过程结束 ,呈剪刃状的南、北两个板块逐渐拼合 ,中特提斯的中、西段主体亦相继消亡 ,仅余西南部部分海域。白垩纪末 ,由于新特提斯洋壳向北大规模俯冲的强力推动 ,冈底斯 念青唐拉板块和羌塘 三江板块完全汇聚并发生陆 陆碰撞 ,中特提斯在洋壳和过渡型地壳褶皱、冲断的盆内汇聚和碰撞造山?
Middle Tethys is the ocean between the middle and late Mesozoics in the South and North China continents. After the ocean was extinct in the Late Cretaceous, the Baogong Lake Nujiang plate belt, which lasted for more than 1,000 kilometers, left behind. Among the numerous research results, there has been a great disagreement on the major issue of how the Central Tethys vanished. Many researchers hold the view that the subduction of the oceanic crust (the East Pacific model) has a southward or northward divergence. The author thinks that Middle Tethys is a special ocean with many different oceanic basins that are different from each other and different in time. There is no large-scale oceanic shell subduction during the demise, The pattern of extinction in the basin, that is, the disappearance of Middle Tethys, consists of the Upper Triassic Qiangtang Sanjiang plate and the Gangdise Nyainqentanglha plate and the Jiayuqiao anger mountain body in the late Jurassic. At the beginning, the central and western segments were still basically in an expansion state at this time, and the land fragmentation was at the same time as the emergence of a new narrow small oceanic basin. Middle Tethys was scissors-shaped in the east and west. In the middle-late Jurassic, the complex terrain from the tectonic terrain to the Sanjiang plate of the Qiangtang plate and the new terrane fissured from the southern part of the earth appeared on the north side of the mid-western section. By the end of the Early Cretaceous, the collapsing of the old and the new earth and the end of the rift had ended. The southern and northern sections with scissor-blade edges gradually merged, and the middle and western sections of Middle Tethys also disappeared, leaving only the remaining part of the southwest Part of the sea. At the end of the Cretaceous, due to the large-scale subduction of the Neo-Tethys oceanic crust to the north, the Gangdese Nyain-Qingtangla plate and the Qiangtang Sanjiang plate completely converged and collided with each other. Crust crust, thrust basin convergence and collision orogeny?