PALEOTETHYS IN SOUTH CHINA,PERMIAN OROGENY AND THE EASTWARDS EXTENSION OF INTERCHANGE DOMAIN

Ma Wenpu (China Univeristy of Geosciences, Beijing 100083)  

outh China continent was formed by the collage of Yangtze Craton and Cathaysia block,the latter shares some common features with the blocks in Paleotethyan multi-islands ocean like indochina, Sibumasu and Lhasa etc., such as lack of Sinian tillites, the limit between basement and cover is located within Cambrian, and many deformation events in early Paleozoic. Instead of conven-tional concept of post-Caledonian platform in South China, a series of evidence reveals that a branch of Paleotethyan ocean passed through the interior of the continent, liking the Song Da belt of Vietnam in the west with the late-Paleozoic Tethyan fauna-bearing oceanic affinity terrains in Asian margin like Akiyoshi seamount and Yanji terrane in the east.Qinfang trough extending from coast of northeastern Vietnam through Guangh to northern Guangdong is the west segment of Paleotethys, where dark thin bedded Radiolaria sillcalites ranging from late Devoaian to mid-Permian are associated with Mn, Ni, Co deposits but lack of terrigenous elastic layer. Eastwards along the strike of silicalites zone, there are blocks of Devonian pillow lava in late Paleozoic melange. Qinfang through separated northern platform, represented by extensive coal-bearing Longtan Formation, by a south-facing continental slope where mid-Perminan flysch appeared. The features of eastern Paleotethyan segment include Carbonifeous-Permian Radiolaria cherts among the ophiolite suite in northeastern Jingxi, which previously have been considered as Proterozoic age, the melange of southern Zhejiang, which contains Permian coal-beaing rocks and marble, and the late Permian to early Triassic turbitite and contourite in Fujian. Intense Mesozoic thin-skinned thrusting have made them dissembered. Late Permian coarse molasse every-where unconformable covers the silicalites in Qinfang area indicating the Paleotethyan close time in South China, large-scale S-type granitoid batholiths were emplaeced about the same time.

【Key Words】： Paleotethys South China Permian Orogeny
【Fund】： 国家自然科学基金 中国科学院岩石圈开放实验室资助
【CateGory Index】： P542.2

Download(CAJ format) Download(PDF format)

CAJViewer7.0 supports all the CNKI file formats; AdobeReader only supports the PDF format.