SHRIMP zircon U-Pb dating of a small tonalite intrusion in metamorphic belt of Chinese Altai orogen and its geological implication  

作　　者：WANG Wei(RZ) WEI Chunjing ZHANG Yinghui CHU Hang ZHAO Yue LIU Xiaochun 

机构地区：[1]Institute of Geomechanics,Chinese Academy of Geological Sciences [2]Key Laboratory of Orogenic Belts and Crustal Evolution,School of Earth and Space Sciences,MOE,Peking University [3]Institute of Geology and Mineral Resources

出　　处：《Global Geology》2013年第4期184-191,共8页世界地质（英文版）

摘　　要：Small granitic intrusions occur in the progressive metamorphic belts of the Chinese Ahai orogen. SHRIMP U-Pb analyses were performed on zircons separated from a tonalite intrusion and yielded a concordant age of 409.6±3.7 Ma （ MSWD = 0.93 ）, restricting the emplacement and crystallization of the tonalite intru- sion to the Early Devonian. Combined with the existing geological data of the contemporary large granitic plutons in the Chinese Altai orogen, the tonalite is considered to be formed together with other granitic rocks in a continental arc setting. The tonalite intrusion has consistent foliation with its country rocks, indicating the strain resuiting in the regional deformation should be very strong during or after the early Devonian.Small granitic intrusions occur in the progressive metamorphic belts of the Chinese Altai orogen.SHRIMP U-Pb analyses were performed on zircons separated from a tonalite intrusion and yielded a concordant age of 409.6±3.7 Ma(MSWD=0.93),restricting the emplacement and crystallization of the tonalite intrusion to the Early Devonian.Combined with the existing geological data of the contemporary large granitic plutons in the Chinese Altai orogen,the tonalite is considered to be formed together with other granitic rocks in a continental arc setting.The tonalite intrusion has consistent foliation with its country rocks,indicating the strain resulting in the regional deformation should be very strong during or after the early Devonian.

关 键 词：TONALITE SHRIMP zircon U-Pb dating DEVONIAN Altai metamorphic belt 

分 类 号：P597.3[天文地球—地球化学] P588.122[天文地球—地质学]