青海唐古拉山中段地区二叠纪地层新资料
NEW DATA OF PERMIAN STRATA IN THE CENTRAL SECTOR OF THE TANGGULA MOUNTAINS,QINGHAI
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摘要: 唐古拉山中段二叠纪地层取得一些新资料,可划分为二统、五岩组。下二叠统开心岭群分为三个岩组,其上部和下部为灰岩组,中部为长石—石英砂岩组,总厚达1971m。自下而上建立Staffella mollerona—Nankinella orbicularia组合带,Neoschwagerina带及Yabeina带,生物组合面貌与华南栖霞组和茅口组基本相同。上二叠统乌丽群,其下部为含煤碎屑岩组,上部为灰岩夹碎屑岩组,总厚达2000m。分别建立Gigantopteris nicotianae folia—Pecopteris(Asterotheca)guizhouensis组合,Palaeofusulina—Perigeyerella costellata组合带,与华南龙潭组及长兴组可以对比。该群与藏北双湖区热觉茶卡组,藏东昌都区妥坝组,青海玉树区东茅陇组,均产特提斯型动物群和华夏植物群,它们同属于一个含煤构造带。Abstract: A new Permian section was measured in the central sector of the Tanggula Mountains and substantial data of fossils were obtained. The strata are divided into two groups and five rock formations. The Lower Permian Kaixingling Group is divided into three rock formations. Its upper and lower parts are marked by the limestone formation and the middle part the feldspar-quartz sandstone formation, totalling up to 1971 m, and from below upward the Stuffella mollerona-Nankinella orbicularia assemblage zone, Neoschwagerina zone and Yabeina zone are established. Their paleontological aspects are in the main identical to those of the Qixia Formation and Maokou Formation of South China. The Upper Permian Wuli Group is composed of the coal-bearing clastic rock formation in the lower part and the formation of limestone with clastic rocks in the upper part, having a total thickness up to 2000 m. The Gigantopteris micotianaetiaefolia-Pecopteris (Asterotheca) guizhouensis assemblage zone and the Palaeofusulina-Perigeyerella costellafa assemblage zone have been established respectively, which may be correlated with the Longtan Formation and the Changxing Formation of South China. This group and the Rejue Caka Formation of the Shuanghu area of northern Tibet, Tuba Formation of the Qamdo area of Sichuan and Dongmaolong Formation of Yushu region of Qinghai all yield the Tethyan faunas and Cathnysian floras. They belong to the same coal-bearing tectonic belt.