地质与勘探2011，Vol.47Issue(1)：11-19,9.
冈底斯东段羌堆铜钼矿床年代学、矽卡岩石榴石成分及其意义
Zircon U-Pb Geochronology and Garnet Composition of the Qiangdui Cu-Mo Deposit in the Eastern Section of Gangdese and Their Significances
摘要
Abstract
The Qiangdui Cu-Mo deposit is a newly discovered porphyry-skarn type deposit in the eastern section of the Cangdese metallogenetic belt. Argillic monzogranite porphyry is the major ore-forming rock. In this study, ore-forming monzogranite porphyry yields the precise LA-ICP-MS zircon U -Pb age of 16.7±0.9Ma, confirming this deposit formed in the Miocene. This age indicates that the Qiangdui Cu-Mo deposit belongs to the same metallogenetic event as the Qulong and Tinggong Cu-Mo deposits, Jiama Cu-Pb-Zn deposit in the central Cangdese belt. Additionally, the systematic researches of garnets in the skarn indicate the early-stage skarn is dominated by grossular, and the late-stage skam is dominated by andradite. This observation also suggests that the salinity and temperature of ore-forming fluid gradually decrease, while oxygen fugacity and pH gradually increase. Besides, partial garnets show high content of F, possibly suggesting the ore-forming fluids have a certain amount of F. It is worth noting that the quartz-chalcopyrite-molyb-denite veinlets occur in the skarn, implying they may be superposed by the later hydrothermal activity similar to the porphyry type deposit. Ore-forming monzogranite porphyry apophyses appear in the drill holes. These observations may indicate that there is a prospecting potential of the porphyry type mineralization in the deep subsurface.关键词
LA-ICP-MS锆石U-Pb定年/羌堆铜钼矿床/石榴石成分/中冈底斯东段Key words
LA-ICP-MS zircon U-Pb age, garnet, Qiangdui Cu-Mo deposit, eastern section of Gangdese分类
地质学引用本文复制引用
李金祥,赵俊兴,秦克章,李光明,林金灯,肖波,江化寨,韩逢杰,黄树峰,陈雷..冈底斯东段羌堆铜钼矿床年代学、矽卡岩石榴石成分及其意义[J].地质与勘探,2011,47(1):11-19,9.基金项目
本文受中国冶金地质总局"冈底斯东段南部矽卡岩-斑岩Cu-Au-Mo矿床成矿模式及成矿条件综合研究"和国家自然科学基金(编号:40772066)资助. （编号:40772066）
