Timing of mineralization at the Shihu gold deposit in the middle segment of the Taihang Mountain, China  

作　　者：Chao Chen Shuyin Niu Fang Wang Fuxiang Zhang Qinglian Zhang Baojun Ma Aiqun Sun Jianzhen Zhang Yaqi Cao Xiaoqing Zhang 

机构地区：[1]Hebei GEO University, Shijiazhuang 050031, China

出　　处：《Acta Geochimica》2018年第1期80-89,共10页地球化学学报（英文）

基　　金：funded by NSFC (No. 40872137);Hebei Natural Foundation (No. D2015403013);Science and Technology Research Project of Colleges and Universities in Hebei Province (No. ZC2016060);Doctor Foundation of Hebei GEO University (No. BQ201320)

摘　　要：The Shihu gold deposit, located in the middlesouth section of the core of the Fuping mantle branch structure, is hosted in the Archean Fuping Group and adjacent to the quartz diorite porphyrite. The gold deposit is the only large gold deposit with reserves of more than 30 tons gold discovered in western Hebei Province so far. In order to constrain the timing of mineralization of this ore deposit, this paper focuses on the isotopic dating of zircon and pyrite. Zircons in gold-bearing quartz veins are magmatic in origin and no hydrothermal zircon has been found in such quartz veins, indicating that zircons were derived from the wall rocks. U–Pb ages of zircons fall mainly in the two domains: 2492 ± 82 and 136 ± 4 Ma, respectively,indicative of the contribution of the Fuping-Group TTG gneiss and Yanshanian igneous rocks, respectively. The Re–Os isotopic compositions of pyrites in the gold-bearing quartz veins yield an isochron age of 127 ± 31 Ma. Combined with other dating results, we suggest that the main metallogenic age of the Shihu gold deposit is 120–127 Ma.The Shihu gold deposit, located in the middle- south section of the core of the Fuping mantle branch structure, is hosted in the Archean Fuping Group and adjacent to the quartz diorite porphyrite. The gold deposit is the only large gold deposit with reserves of more than 30 tons gold discovered in western Hebei Province so far. In order to constrain the timing of mineralization of this ore deposit, this paper focuses on the isotopic dating of zircon and pyrite. Zircons in gold-bearing quartz veins are mag- matic in origin and no hydrothermal zircon has been found in such quartz veins, indicating that zircons were derived from the wall rocks. U-Pb ages of zircons fall mainly in the two domains： 2492 i 82 and 136 ± 4 Ma, respectively, indicative of the contribution of the Fuping-Group TTG gneiss and Yanshanian igneous rocks, respectively. The Re-Os isotopic compositions of pyrites in the gold-bearing quartz veins yield an isochron age of 127 - 31 Ma. Com- bined with other dating results, we suggest that the main metallogenic age of the Shihu gold deposit is 120-127 Ma.

关 键 词：Mantle branch structure Shihu gold deposit Zircon U–Pb dating Pyrite Re–Os dating Gold-bearing quartz vein 

分 类 号：P[天文地球]