中文摘要:在系统研究墨江金矿床地质事件的基础上,以富金石英脉中的石英流 体包裹体为测定对象,获得Rb_Sr等时线年龄为(135±3) Ma。上三叠统地层中含金石英脉旁 侧发育的铬水云母脉K_Ar法年龄为(109.5±1.7) Ma。结合前人的研究资料,认为墨江金矿 床经历了多期次成矿作用,其中构成本矿床的主体——富金石英脉的形成时代可能为135~9 0 Ma,相当于燕山晚期。
Abstract:The Mojiang gold deposit, one of the most important large gold deposits in the “Sanjiang" gold mineralization area of Yunnan Province, has great potential in increasing its gold reserves. Knowledge of its metallogenic age is very insuffic ient, which has restricted the study of its origin and the ore prognosis. Based on systematical analysis of geological events in this area, this paper deals wit h metallogenic ages of the Mojiang gold deposit. The samples studied were taken from quartz in gold_rich quartz veins at various levels, and the fluid inclusion Rb_Sr isochronal ages are (135±3) Ma. The K_Ar isotopic age of Cr_hydromuscovi te from gold_bearing quartz veins in Upper Triassic Waigucun Formation is (109.5 2±1.69) Ma. According to regional geological characteristics and geochronologic al investigations, the authors consider that the Mojiang gold deposit has underg one repeated polymetallic ore_forming activities, and that the main orebodies of the ore deposit, i.e., the gold_rich quartz veins, might have been formed at 13 5~90Ma.
keywords:geochemistry, fluid inclusion, metallogenic age, gold_bearin g quartz, Mojiang, Yunnan province
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基金项目:中国科学院创新项目(编号:KZCX3_SW_125)、国家重点基础项目(编号:G1999043210 )、国土资源大调查项目(编号:M0303)和南京大学内生金属矿床成矿机制研究国家重点实验 室开放基金(编号:10_04_05)
引用文本:
谢桂青,胡瑞忠,毛景文,方维萱,李瑞玲.2004.云南省墨江金矿床成矿时代探讨[J].矿床地质,23(2):253~260.2004.Discussion on Metallogenic Ages of Mojiang Gold Deposit in Yunnan Province[J].Mineral Deposits23(2):253~260
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