^(40)Ar-^(39)Ar Age of K-feldspar from K-feldspar Granite in the Qiaohuote Copper Deposit, Bayanbulak, Xinjiang, and Its Geological Significance  

作　　者：WANGZhiliang MAOJingwen YANGJianmin CHENWen ZHANGZuoheng 

机构地区：[1]InstituteofMineralResources,ChineseAcademyofGeologicalSciences,Beijing100037 [2]InstituteofMineralResources,ChineseAcademyofGeologicalSciences,Beijing100037／／FacultyofGeosciencesandResources,ChinaUniversityofGeosciences,Beijing100083 [3]InstituteofGeology,ChineseAcademyofGeologicalSciences,Beijing100037

出　　处：《Acta Geologica Sinica(English Edition)》2004年第2期428-434,共7页地质学报（英文版）

摘　　要：By using the 40Ar-39Ar chronological method to date K-feldspar from K-feldspar granite in the Qiaohuote copper district, the authors obtained a plateau age of 274.78±0.44 Ma and an isochron age of 272.7±3.0 Ma. Because there is no tectonic deformation overprinted or hydrothermal alteration in the K-feldspar granite intrusion after its emplacement, the 40Ar-39Ar age represents the crystallization age of K-feldspar in K-feldspar granite, i.e. the late crystallization age of the K-feldspar granite intrusion, which indicates that the K-feldspar granite formed in the intraplate extensional stage during the Early Permian. Moreover, based on the spatial relationship between the K-feldspar granite intrusion and copper orebodies, variations of copper ore grade, REE characteristics of K-feldspar granite and copper ores, and H and O isotopic compositions of fluid inclusions in copper ores, the metallogenesis of the Qiaohuote copper deposit is directly related to intrusive activities of the K-feldspar granite, and thus the crystallization age of K-feldspar in the granite approximately approaches the metallogenic epoch of the Qiaohuote copper deposit.By using the 40Ar-39Ar chronological method to date K-feldspar from K-feldspar granite in the Qiaohuote copper district, the authors obtained a plateau age of 274.78±0.44 Ma and an isochron age of 272.7±3.0 Ma. Because there is no tectonic deformation overprinted or hydrothermal alteration in the K-feldspar granite intrusion after its emplacement, the 40Ar-39Ar age represents the crystallization age of K-feldspar in K-feldspar granite, i.e. the late crystallization age of the K-feldspar granite intrusion, which indicates that the K-feldspar granite formed in the intraplate extensional stage during the Early Permian. Moreover, based on the spatial relationship between the K-feldspar granite intrusion and copper orebodies, variations of copper ore grade, REE characteristics of K-feldspar granite and copper ores, and H and O isotopic compositions of fluid inclusions in copper ores, the metallogenesis of the Qiaohuote copper deposit is directly related to intrusive activities of the K-feldspar granite, and thus the crystallization age of K-feldspar in the granite approximately approaches the metallogenic epoch of the Qiaohuote copper deposit.

关 键 词：40Ar-39Ar age K-feldspar granite Qiaohuote XINJIANG 

分 类 号：P578.11[天文地球—矿物学] P629[天文地球—地质学]