地质通报2016，Vol.35Issue(5)：700-710,11.
东昆仑东段清水泉辉长岩体LA-ICP-MS锆石U-Pb年龄、地球化学特征及其构造意义
LA-ICP-MS zir-con U-Pb dating of the Chahantaolegai syenogranites in Xiangride area of East Kunlun and its geological significance
摘要
Abstract
Located in central Eastern Kunlun suture zone on the northern side of Qingshuiquan ophiolite, the Qingshuiquan gabbro consists mainly of hornblende gabbros. The LA-ICP-MS zircon U-Pb age is 452.1 ± 5Ma, suggesting the formation of gabbro in Late Ordovician. The gabbro samples have 43.89%~45.99%SiO2, 1.30%~2.32%Na2O, 0.68%~1.39%K2O, and 5.72%~6.54%MgO, with low P2O5 (0.26%~0.40%), TiO2(0.74%~0.95%) and Mg#(53~54). The geochemical characteristics indicate that the gabbro be⁃longs to tholeiitic rocks;REE patterns show that the rocks are enriched in LREE and depleted in HREE;the trace elements are char⁃acterized by enrichment of LILE (Cs,Rb,Ba,especially positive anomaly of Ba) and obvious depletion of HFSE (Nb,Ta,Ti,Zr and Hf). Tectonic discrimination diagrams indicate that the gabbro formed in an island arc setting of active continental margin. Combined with regional studies, the authors hold that Qingshuiquan gabbro rocks might have formed at the initial stage of the northward sub⁃duction of Central Eastern Kunlun back-arc limited ocean, represented by the Qingshuiquan ophiolite.关键词
清水泉/辉长岩体/岛弧/LA-ICP-MS锆石U-Pb测年/晚奥陶世Key words
Qingshuiquan/gabbro/island arc/LA-ICP-MS zircon U-Pb dating/Late Ordovician分类
天文与地球科学引用本文复制引用
桑继镇,陈功,邓文兵,裴先治,李瑞保,刘成军,陈有炘,李佐臣,陈国超,杨森,王旭斌..东昆仑东段清水泉辉长岩体LA-ICP-MS锆石U-Pb年龄、地球化学特征及其构造意义[J].地质通报,2016,35(5):700-710,11.基金项目
国家自然科学基金项目（批准号41472191、41502191、41172186）、高等学校博士学科点专项科研基金项目（编号20110205110004）和中央高校基本科研业务费专项资金项目 （）
