赣南葛廷坑钼矿辉钼矿Re-Os年龄及其地质意义

Re-Os dating of molybdenites from Getingkeng molybdenum deposit of Southern Jiangxi Province and its geological significance

赣南葛廷坑钼矿为产在花岗斑岩与围岩内外接触带的中型斑岩型钼矿床。通过对矿区含矿石英脉中7个辉钼矿样品进行Re-Os同位素测定,获得等时线年龄及模式年龄的加权平均值分别为（159.4±1.6）和（158.8±1.3）Ma。等时线初始187Os为（0.001±0.055）ng/g,MSWD=1.7。葛廷坑钼矿形成于中侏罗世中晚期,其成矿年龄对应于华南中晚侏罗世第二成矿阶段（170~150 Ma）,与区域内160 Ma左右的钨锡矿成矿作用基本一致。区域上华南钼的成矿时间具有连续性,在165~90 Ma均有发生。

Located in the inside and outside contact zone of granite porphyry,the Getingkeng molybdenum deposit is a medium-sized porphyry deposit in southern Jiangxi Province.Re-Os isotopic dating of 7 molybdenite samples from the mineralized quartz veins of Getingkeng deposit has yielded a precise isochron age of（159.4±1.6） Ma and a weighted average model age of（158.8±1.3） Ma.The intercept of isochron is（0.001±0.055）ng/g,and the MSWD is 1.7.Getingkeng molybdenum deposit formed in the Mid-Late Middle Jurassic,the mineralization age corresponds to the second mineralization stage（170-150 Ma） in the Late Jurassic of South China,consistent with the tungsten-tin mineralization around 160 Ma within the region.South molybdenum mineralization occurred in a row of 165-90 Ma.