Characteristics and genesis of Kanggur gold deposit in the eastern Tianshan mountains,NW China:evidence from geology,isotope distribution and chronology
会议名称：《中国科学院地质与地球物理研究所2003学术年会》
会议日期：2003年
学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程]
基 金：supported by the Ministry of Science and Technology of China (2001CB 409805) National 305 Research Scholarship
关 键 词：Isotope Geochronology Shear zone Orogenic gold NW China
摘 要：The Kanggur gold deposit lies in East Tianshan mountains,eastern section of Central Asia orogenic *** gold mineralization occurs on the northern margin of the Aqishan-Yamansu island arc in the Tarim *** is mainly hosted in Lower Carboniferous volcanic rocks,and controlled by syn-tectonic intrusions and the ductile shear zone. The host rock is a calc-alkaline volcanic rock series consisting of andesite,dacite,tuff and subvolcanic *** gold ore bodies were distributed in transition zone from strong ductile deformation to weak ***-controlling structure is EW-trending normal brittle-ductile shear *** gold ore bodies are composed of Au-bearing altered rocks and a few Au-bearing sulfide-quartz *** mineralization shows vertical zonation in which Au was enriched in the upper ***-Pb-Zn were enriched in the middle and Au-Cu were enriched in the lower *** to mineral assemblages and alteration intensity,hydrothermal alteration could be divided into three zones:***. pyrirization and magnetization zone(major ore body);pyrite-phyllic rock and/or sericite alteration zone;and sericite-chlorite alteration *** mineralization stages are identified on the basis of mineral assemblage and crosscutting relationship of veins. TheδS values of sulfide in the ores range from - 0.9‰to + 3.3‰,similar to those of the volcanic and subvolcanic rocks (-3.21～+1.3‰),indicating that the sulfur isotope composition is characterized by unfractionated mantle *** lead isotope compositions of ores are between those of the volcanic rocks and subvolcanic *** initial Sr/Sr ratios of the ores vary between 0.7077 and 0.7106,similar to those of the host rocks(0.7079-0.7125).According to the Sr,S and Pb isotopic data,it is indicated that the ore-forming materials were derived from the surrounding volcanic rocks and feature deep ***δO values of the ore fluids vary from +3.83‰to - 1.77‰c and theδD values