河南银洞沟银金钼矿床铼-锇同位素定年和加里东期造山-成矿事件

Re-Os isotope dating of the Yindonggou Ag-Au-Mo deposit,Henan province and its implication for Caledonian orogenic-metallogenic event

河南内乡银洞沟银金钼矿床是夏馆银多金属矿田新发现的造山型矿床,赋矿地层为新元古代-早古生代弧后盆地堆积的二郎坪群火山-沉积岩系,二郎坪群在志留纪或加里东运动中遭受区域变形和变质。矿床5件辉钼矿Re-Os同位素模式年龄介于423.4±4.4～432.2±3.4Ma,加权平均年龄为429.3±3.9Ma(MSWD=0.73),指示秦岭地区存在显著的加里东期造山-成矿事件。

The Yindonggou Ag-Au-Mo deposit,located in Neixiang County,Henan Province,is a recently discovered orogenic-type ore deposit in the Xiaguan Ag-dominant poly-metal ore-field.The deposit is hosted in the Erlangping volcanic-sedimentary sequence which was deposited in a Neoproterozoic-Early Paleozoic back-arc basin and regionally deformed and metamorphosed in Caledonian Movement or Silurian period.Five molybdenite samples from the deposit yield Re-Os isotope model ages of 423.4±4.4～432.2±3.4 Ma,with an average...