The Fossils in Shangxi Group and Its Implication for Tectonics, Southern Anhui, China  

作　　者：徐树桐 陈冠宝 陶正 石永红 孙枢 Kenneth J.Hsu 尹磊明 欧阳舒 廖卓庭 

机构地区：[1]Anhui Institute of Geology, Hefei 230001, PRC [2]Institute of Geology, Academia Sinica, Beijing 100029, PRC [3]Swiss Federal Institute of Technology, CH-8092 Zurich, Switzerland [4]Nanjing Institute of Geology and Palaeontolgy, Academia Sinica, Nanjing 210008, PRC

出　　处：《Science China Chemistry》1994年第3期366-376,共11页中国科学（化学英文版）

基　　金：This work was supported by the grant from Anhui Bureau of Geology and Mineral Resources,and from the National Natural Science Foundation of China.

摘　　要：The Shangxi Group is the local name in southern Anhui Province and it is believed to be the equivalence of the well-known Banxi Group in Hunan Province, southern China. So the area occupied by the Shangxi Group was regarded as a part of the 'Jiangnan old land' of Presinian till it was challenged by the present authors years ago. After we postulated that there may be some strata of Palaeozoic Era in Shangxi Group, some microfossils and then macrofossils of Palaeozoic were found in some part of it. The macrof os-sils, Lingula sp. , Conulariid and the microfossils indicate that most units of the Shangxi Group are Palaeozoic strata. Based on the discovery of these fossils and the recognition of the tectonic-setting of the different tectono-petrologic units in the Shangxi Group, three different stratigraphic sequences (island-arc volcanics, back-arc sediments and the cover of passive margin of Yangtze Continental Plate) are established and the tectonic evolution of them is postulated in the present paper. All the evidences obtained recently from the Shangxi Group indicate that there is no 'Old Land' over the discussed area, but a subduction followed by a collision zone between the island-arc and Yangtze Continental Plate; all these metamorphosed strata were originally island-arc, back-arc basin sediments during the Sinian-late Paleozoic, except the Presinian sandstone distributed in a narrow belt on the northmost margin of the metamorphic terrane.The Shangxi Group is the local name in southern Anhui Province and it is believed to be the equivalence of the well-known Banxi Group in Hunan Province, southern China. So the area occupied by the Shangxi Group was regarded as a part of the "Jiangnan old land" of Presinian till it was challenged by the present authors years ago. After we postulated that there may be some strata of Palaeozoic Era in Shangxi Group, some microfossils and then macrofossils of Palaeozoic were found in some part of it. The macrof os-sils, Lingula sp. , Conulariid and the microfossils indicate that most units of the Shangxi Group are Palaeozoic strata. Based on the discovery of these fossils and the recognition of the tectonic-setting of the different tectono-petrologic units in the Shangxi Group, three different stratigraphic sequences (island-arc volcanics, back-arc sediments and the cover of passive margin of Yangtze Continental Plate) are established and the tectonic evolution of them is postulated in the present paper.

关 键 词：Jiangnan old land FOSSIL tectono-petrolagic unit. 

分 类 号：Q911[天文地球—古生物学与地层学]