青海乌兰乌珠尔地区晚志留世过铝质花岗岩地质特征及意义  

Geological characteristics and significance of the peraluminous granite in late silurian epoch in Wulanrvuzhuer region of Qinghai

作　　者：谈生祥[1] 郭通珍[1] 董进生[1] 常有英[1] 马文[1] 

机构地区：[1]青海省地质调查院,青海西宁810012

出　　处：《青海大学学报（自然科学版）》2011年第1期36-43,共8页Journal of Qinghai University(Natural Science)

摘　　要：在乌兰乌珠尔地区发现的晚志留世过铝质花岗岩由花岗闪长岩、二长花岗岩组成,具中细粒结构,以富含黑云母,石榴子石和电气石等富铝矿物及暗色微细粒闪长质包体发育为特征,富铝高钾,铝饱和指数A/CNK=1.02～1.28,稀土总量ΣREE=88.98～199.88μg/g,LREE/HREE=5.29～18.15,属轻稀土富集型,δEu=0.53～0.67为铕负异常,微量元素构造环境判别显示其形成于同碰撞构造环境。二长花岗岩的LA-ICP-MS锆石U-Pb同位素年龄为413±5 Ma(MSWD=1.4,probability=0.18)。说明该类花岗岩的形成时代为晚志留世,同时也揭示出祁漫塔格的碰撞造山阶段。The late silurian epoch peraluminous granites found in Wulanwuzhuer region are formed by granodiorite and monzogranite and the peraluminous granites are of medium fine texture,with rich biotite,garnet and tourmaline with rich aluminum and high potassium.Its aluminum saturation index is A/CNK=1.02～1.28,its rare earth elements guantity ΣREE=88.98～199.88 μg/g,LREE/HREE=5.29～18.15 and they belong to rich light rare earth element type.δEu=0.53～0.67 is a negative Eu anomaly and according to geochemistry and the trace element tectonic discrimination,the granites are come into being the syn-coLG tectonic environment.Monzogranite LA-ICP-MS zircon U-Pb isotopic age of monzogranite is 413±5 Ma（MSWD=1.4,probability = 0.18）.It shows that such granite formed epoch is late Silurian epoch and it was revealed the collisional stage of Qimatage.

关 键 词：乌兰乌珠尔地区 晚志留世 过铝质花岗岩 同碰撞造山 

分 类 号：P53[天文地球—古生物学与地层学]