地质通报2018，Vol.37Issue(5)：805-818,14.
新疆西准噶尔塔尔根一带花岗岩锆石U-Pb年龄、地球化学特征及其地质意义
Zircon U-Pb chronology, geochemistry of the Taergen granite in Western Junggar, Xinjiang, and their geological significance
摘要
Abstract
There are large numbers of intermediate-acid intrusions distributed along the Darbut tectono-magmatic belt in Western Junggar,Xinjiang.It is of great significance to understand the regional magmatic evolution through their petrogenesis and emplacement periods.The formation time,petronenesis and tectonic setting of Taergen granites,located in the northem part of Mayile Mountain,are reported in this study through field observation,LA-ICP-MS zircon U-Pb dating and geochemical analysis.The Taergen granites are mainly composed of monzonitic granite and syenogranite,LA-ICP-MS zircon U-Pb dating of monzonitic granite yielded an age of 296.6±2.0Ma (n=27,MSWD=0.33),corresponding to early Early Permian.Petrogeochemical analysis indicates that Taergen granites are characterized by high silica,alkali,low titanium and aluminum,lean calcium and magnesium.They are also enriched in large ion lithophile elements (e.g.Rb,Th,K) and high strength field elements (e.g.Zr,Hf) and are strongly depleted in Sr,Eu,P,Ti and mediate depleted in Ba,Nb,Ta,with high 104Ga/Al ratios and Zr+Nb+Ce+Y contents.These features indicate that Taergen granites are metaluminous to weakly peraluminous alkaline series A-type granite,which were originated from the partial melting of felsic crust under high temperature and low pressure conditions.Combined with regional tectonic evolution and previous results,we suggest that the Western Junggar region was still in a subduction-dominated setting in the Late Carboniferous-Early Permian,and probably associated with the ridge subduction during Late Carboniferous period.关键词
A型花岗岩/岩石成因/早二叠世早期/俯冲/西准噶尔Key words
A-type granite/petrogenesis/early Early Permian/subduction/Western Junggar分类
天文与地球科学引用本文复制引用
支倩,李永军,王冉,段丰浩,晁文迪,石歌..新疆西准噶尔塔尔根一带花岗岩锆石U-Pb年龄、地球化学特征及其地质意义[J].地质通报,2018,37(5):805-818,14.基金项目
国家自然科学基金项目《西准噶尔玉依塔勒盆克提花岗岩中石榴石的形成机制及地质意义》(批准号:41402044)和新疆国土厅地质勘查基金项目《新疆西准噶尔地区构造-岩浆带成矿地质作用及矿化特征调查与研究》(编号:Y14-5-LQ06)、《新疆东、西准噶尔泥盆系—石炭系典型剖面对比研究》(编号:Y15-1-LQ01) （批准号:41402044）
