【作者】 高延林； 吴向农； 左国朝；

【Author】 Gao Yanlin (The committe on science andtechnology of Qinghai) Wu Xiangnong (Institute of geology,Qinghai) Zuo Guochao (Institute of geology and mineral resources of Gansu)

【机构】 青海省科学技术委员会； 青海省地质研究所； 甘肃省地质研究所；

【摘要】 出露在青海省都兰县南部布尔汗布达山主脊部位的清水泉蛇绿岩是作者1986年新发现的,它为厘定昆仑山中央大断裂的早古生代缝合带性质从岩石学上提供了有力的板块构造证据。本文从区域地质、产出状态、岩石组合、地球化学、形成时代等方面对清水泉蛇绿岩进行了较详细的论证。同时根据蛇绿岩的特征和成因,结合区域地质和地球物理新资料,提出了昆中断裂是东昆仑地区的一条加里东期古缝合带的新认识,并且认为昆中古缝合带就是青海境内柴达木地块与华南地块的界线,而沿此线保存的清水泉蛇绿岩则可能代表着早古生代秦祁昆古大洋壳在东昆仑地区的残迹。更多还原

【Abstract】 The Qingshuiquan ophiolitic blocks or sheets,which are located in the Qingshuiquan and adjacent area about 60 km away from the Dulan county of Qinghai province,have been first discoved during field exploration in 1986.The ophiolites are occurrenced as tectonic sheets or blocks along the middle fracture zone of the East Kunlun in NWW direction.Among some bigger blocks or sheets are the more complete sequences of ophiolite suite,which are re-established from bottom to top as follow:1.massive peridotites and harzburgitr;2.cumu- lative complex,such as the bedded structural harzburgite and dunite,troctolite as well as olivine-gabbro,gabbro;3.diabase and gabbroid-diabase sill and diabase vein;4.basalt,etc.The ophiolite or ophiolitic melange were emplaced or obdu- eted on the continental margin of the south China plate when the Qinqikun (Qinling—qilian—Kunlun Mt.)ancient oceanic crust subduction and collision of the Tarim-Qaidam plate with the south China plate,from north towards south, hence,the ophiolitic blocks or sheets have become an important evidences for the East Kunlun suture of the Early Paleozoic from the rock record of plate tectonice.更多还原