^(40)Ar/^(39)Ar Dating of the Shaxi Porphyry Cu-Au Deposit in the Southern Tan-Lu Fault Zone, Anhui Province  

作　　者：YANG Xiaoyong ZHENG Yongfei XIAO Yilin DU Jianguo SUN Weidong 

机构地区：[1]CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui 230026 [2]CAS Key Laboratory oflsotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, Guangzhou, Guangdong 510640 [3]Anhui Institute of Geological Survey, Hefei, Anhui 230001

出　　处：《Acta Geologica Sinica(English Edition)》2007年第3期477-487,共11页地质学报（英文版）

基　　金：This study is supported by funds from the Ministry of Science and Technology of China （2006CB403500） ； National Natural Science Foundation of China （40473021）.

摘　　要：Four samples of plagioclase and biotite from the Shaxi porphyry in the lower part of the Yangtze metallogenic belt were analyzed for age determination with the ^40 Ar/^39Ar method. The results yield reproducible ages of 126 Ma to 135 Ma with a high level of confidence according to the agreement between isochron and plateau ages. The four Ar-Ar ages are relatively consistent within the analytical error. These ages are also consistent with, but more precise than, previous K-Ar and Rb-Sr ages and thus provide better constraints on the time of porphyry formation and associated Cu-Au mineralization along the middle to lower part of the Yangtze metallogenic belt. The ages of 126 to 135 Ma are interpreted to represent the intrusive time of the Shaxi porphyry, so that the Cu-Au mineralization should have occurred later due to the post-magmatic hydrothermal event.Four samples of plagioclase and biotite from the Shaxi porphyry in the lower part of the Yangtze metallogenic belt were analyzed for age determination with the ^40 Ar/^39Ar method. The results yield reproducible ages of 126 Ma to 135 Ma with a high level of confidence according to the agreement between isochron and plateau ages. The four Ar-Ar ages are relatively consistent within the analytical error. These ages are also consistent with, but more precise than, previous K-Ar and Rb-Sr ages and thus provide better constraints on the time of porphyry formation and associated Cu-Au mineralization along the middle to lower part of the Yangtze metallogenic belt. The ages of 126 to 135 Ma are interpreted to represent the intrusive time of the Shaxi porphyry, so that the Cu-Au mineralization should have occurred later due to the post-magmatic hydrothermal event.

关 键 词：Shaxi porphyry-type Cu-Au deposit  ^40 Ar/^39 Ar dating Yangtze metallogenic belt Tancheng -Lujiang fault belt East China 

分 类 号：P58[天文地球—岩石学]