巴彦诺日公石英闪长岩位于内蒙古阿拉善北部巴彦诺日公地区，对样品测试LA-ICP-MS锆石U-Pb年龄为（317.45±0.79） Ma，相当于晚石炭世。地球化学特征表明，石英闪长岩属准铝质钙碱性系列岩石，轻重稀土分馏明显，具弱的铕负异常，稀土分布曲线右倾，轻稀土富集，微量元素富集K，Ba，亏损U，Nb，Ti。R1-R2图解中，样品投入碰撞前消减带花岗岩范围，Nb-Y和Rb-Yb+Nb图解中，样品投入火山弧花岗岩区，反映石英闪长岩形成于碰撞前板块边缘岩浆弧环境。%The Bayannuorigong Quartz diorite is located in Bayannuorigong area northern Inner Mongolia of Alxa,LA-ICP-MS zircon U-Pb dating of quartz diorite from the pluton yielded an age of (317.45±0.79) Ma,suggesting an emplace-ment of late Carboniferous epoch.The geochemical characteristics indicate that the quartz diorite are metaluminous and calc-alkaline rocks.The rocks are characterized by obvious REE fractionation,and have weak negative europium anomaly with the rightward Rare earth distribution curve and enrichment of LREE,enrichment of K、Ba elements and depletionU、Nb、Ti.In the R1-R2 diagram,the samples cast upon the pre-collision subduction zone area,In the Nb-Y and Rb-Yb+Nb dia-grams,the samples are all cast upon the area of volcanic arc granite.These Reflect the quartz diorite formed in the plate margin magmatic arc environment before collision.
展开▼
