地质通报2016，Vol.35Issue(5)：674-686,13.
东昆仑东段布青山地区上二叠统格曲组物源分析及其构造意义
Provenance analysis and structural implications of Gequ Formation at the Buqingshan area in the eastern segment of the East Kunlun region
摘要
Abstract
Detailed statistics of gravel composition, gravel granulometry and the LA-ICP-MS U-Pb dating of detrital zircons from conglomerate bed in Delisitan of Buqingshan show that this conglomerate was derived from the nearby place with rapid accumula⁃tion. This conglomerate consists mainly of quartzite and granite and subordinately of siliceous rocks and basic rocks, with minor sand⁃stone and limestone. The coefficients of dispersion are 1.54~2.02 for the gravel of conglomerate. The detrital zircon age spectra can be divided into three groups:①Early Ordovician-Late Silurian age group, 499~409Ma, with the peak value being 426Ma, corre⁃sponding to the tectono-magmatic events associated with Proto-Tethys northward subduction and collision at the end of Early Pa⁃leozoic;②Neoproterozoic age group, 744~619Ma, with the peak value being 744Ma, corresponding to the breakup of Rodinia su⁃percontinent; ③Paleoproterozoic age group, 2443Ma, corresponding to the tectono-magmatic hydrothermal event of East Kunlun in Paleoproterozoic. An integrated analysis of the U-Pb detrital zircon ages and sedimentology characteristics show that the granite gravel was derived from magmatic arc in Caledonian in northern East Kunlun Orogen, the gravel of quartzite and metamorphic rocks was from the East Kunlun metamorphic rock series in basement, and the gravel of sedimentary rocks might have come from the early sedimentary formation in the orogenic belt. A comprehensive analysis reveals that the Gequ Formation is a mollasse formation of the littoral-shallow facie which deposited on anactive continental margin. It represents both the beginning of the Paleo-Tethys north⁃ward subduction and the sedimentary responding of tectonics at the beginning of the subduction.关键词
东昆仑/布青山/上二叠统格曲组/砾岩/物源分析/LA-ICP-MS锆石U-Pb测年Key words
East Kunlun/Buqingshan/Upper Permian Gequ Formation/conglomerate/provenance analysis/LA-ICP-MS zircon U-Pb dating分类
天文与地球科学引用本文复制引用
杨森,邓文兵,裴先治,李瑞保,刘成军,陈有炘,李佐臣,王旭斌,桑继镇,陈功..东昆仑东段布青山地区上二叠统格曲组物源分析及其构造意义[J].地质通报,2016,35(5):674-686,13.基金项目
国家自然科学基金项目（批准号41472191、41172186、41502191）、中央高校基本科研业务费专项资金项目（编号CHD2011TD020、2013G1271091、2013G1271092）和青海省国土资源厅-中国铝业公司公益性区域地质矿产调查基金项目 （）
