巴颜喀拉北部曲旁浪斜地区花岗闪长岩地球化学与年代学

通过对曲旁浪斜花岗闪长岩进行岩相学、岩石地球化学及年代学研究，探讨其成因及构造环境.研究获得曲旁浪斜花岗闪长岩锆石SHRIMP U-Pb年龄213.8±2.0 Ma，表明岩浆侵位时代为中生代晚三叠世.花岗闪长岩具有高Si、Al2O3、Na，低K，贫Ca、Mg、Fe的特点，属SiO2过饱和铝过饱和I型花岗岩；具有明显富集K、Rb、Th，亏损Sm、Hf、Zr、Y、Yb的特征，并且具有负Eu异常.曲旁浪斜花岗闪长岩是陆内碰撞造山阶段深部滑脱构造导致地壳局部熔融的产物.

GEOCHEMISTRY AND GEOCHRONOLOGY OF GRANODIORITES IN QUPANGLANGXIE AREA,NORTHERN BAYANKALA TERRANE

Through the study on the petrography, lithogeochemistry and geochronology of granodiorites in Qupanglangxie area, the paper discusses the genesis and tectonic environment of the intrusive rocks. The SHRIMP zircon U-Pb dating yields a weighted mean age of 213.8±2.0 Ma, indicating that the emplacement occurred in Mesozoic Late Triassic. The granodiorites are characterized by high Si, Al2O3 and Na, low K, poor in Ca, Mg and Fe, belonging to SiO2 supersaturated and aluminum supersaturated I-type granite, with obvious enrichment of K, Rb and Th, deficiency of Sm, Hf, Zr, Y and Yb, and negative Eu anomaly. The granodiorites in the area were formed by the partial melting of crust caused by deep detachment structure in the stage of intracontinental collision orogeny.