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安徽铜山矽卡岩型铜矿床是长江中下游成矿带的重要矿床之一,其2件辉钼矿样品和2件黄铁矿样品的Re-Os同位素年龄分别为150.70±1.14～151.22±1.11Ma和148.73±3.22～152.50±6.69Ma,4件样品的等时线年龄为150.98±0.78Ma(MSWD=0.68,误差2σ)。这一结果表明,铜山铜矿形成于晚侏罗世,而非早白垩世。考虑到前人获得的长江中下游成矿带的成矿年龄介于134Ma和144Ma之间,我们认为长江中下游成矿带的成矿作用主要发生在侏罗纪-白垩纪之交,与构造体制由挤压转向伸展的过程同步。
The Tongshan skarn copper deposit in Anhui Province is one of the important deposits in the metallogenic belt in the middle and lower reaches of the Yangtze River. The Re-Os isotope ages of two molybdenite samples and two pyrite samples are 150.70 ± 1.14 ~ 151.22 ± 1.11Ma and 148.73 ± 3.22 ~ 152.50 ± 6.69Ma. The isochron age of four samples was 150.98 ± 0.78Ma (MSWD = 0.68, error 2σ). This result indicates that the Tongshan copper deposit formed in the Late Jurassic, not the Early Cretaceous. Considering that the metallogenic age of predecessor metallogenic belt in the middle and lower reaches of the Yangtze River is between 134Ma and 144Ma, we believe that the mineralization of the metallogenic belt in the middle and lower reaches of the Yangtze River occurred at the turn of the Jurassic-Cretaceous, System from extrusion to stretch the process of synchronization.