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首次运用Re-Os同位素定年法对武山铜矿南矿带的辉钼矿进行年龄测试,测得5件样品的模式年龄变化于144.0～145.7Ma,等时线年龄为146.4±2.6Ma,与花岗闪长斑岩145±3.9Ma的SISM法年龄值相吻合,表明武山铜矿南矿带成矿与晚侏罗世中酸性岩浆活动关系密切。该矿床北矿带层状、似层状硫化物型矿体曾经历海西期海底喷流-沉积成矿,而燕山期岩浆期后热液叠加改造对其形成具有重要作用,即武山铜矿最终形成于晚侏罗世。以矽卡岩型-(似)层状硫化物型矿化为主的武山铜矿稍早于同属九-瑞矿集区、以斑岩型-(似)层状硫化物型矿化为主的城门山铜矿形成,由于其成矿伴随着下扬子地区岩石圈的大规模减薄事件,成矿时间差很可能是导致两者矿化特征差异的重要原因。武山铜矿及九-瑞矿集区与铜陵、安庆和鄂东南矿集区的成岩成矿时代高度一致,它们是在统一的构造-岩浆作用过程中、与燕山期花岗质岩浆活动有关的产物。
For the first time, Re-Os isotopic dating method was used to test the age of molybdenite in the south ore belt of Wushan Copper Mine. The model age of the five samples was 144.0 ~ 145.7Ma with an isochron age of 146.4 ± 2.6Ma. The SISM method ages of 145 ± 3.9Ma coincide with that of the Gang Dian porphyry, indicating that the mineralization in the south of the Wushan copper deposit is closely related to the acid magmatism in the Late Jurassic. The stratiform and stratified sulphide ore body in the northern ore belt of this deposit experienced the Hercynian submarine jet-sedimentary mineralization, and the superposition of hydrothermal fluids after the Yanshanian magma period played an important role in the formation of the ore body, namely the Wushan Copper Mine Eventually formed in the Late Jurassic. The Wushan copper mine, which is dominated by skarn-like stratified sulfide type mineralization, was earlier dominated by the Jiuyui-Rui ore-gathering area and the porphyry-type stratified sulfide-type mineralization The formation of the Chengmenshan copper deposit is likely to be the major reason for the difference in mineralization characteristics due to its metallogenesis accompanying the large-scale lithospheric thinning in the Lower Yangtze region. The Wushan Copper Mine and Jiuyui Mine Concentration Area are highly consistent with the diagenetic and mineralization age of Tongling, Anqing and southeast Hubei mining areas. They are related to the granitic magmatic activity of Yanshan during the process of unified tectono-magmatism product.