赣北石门寺钨铜多金属矿床辉钼矿Re-Os同位素年龄及其地质意义  

The Re-Os isotopic dating of molybdenite from the Shimensi tungsten-copper polymetallic deposit in the northern Jiangxi and its geological significance

作　　者：刘更更 吴颖宸 魏文凤[1] 严冰[1] 邹志超[1] LIU Geng-geng;WU Ying-chen;WEI Wen-feng;YAN Bing;ZOU Zhi-chao(Institute of Earth Sciences,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]成都理工大学地球科学学院,成都610059

出　　处：《矿物岩石地球化学通报》2024年第1期192-210,共19页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：矿床地球化学国家重点实验室开放基金资助项目(202006,202007)。

摘　　要：为了解赣北石门寺钨铜多金属矿床的钨富集机理及矿床成因,对该矿床中的辉钼矿开展了Re-Os同位素年代学研究。结果显示,6件辉钼矿样品的Re-Os模式年龄为140.2~142.5 Ma,加权平均年龄为(141.37±0.84)Ma(MSWD=0.84),等时线年龄为(141.79±0.97)Ma(MSWD=1.10),二者在误差范围内一致,可以代表辉钼矿的矿化年龄,指示该矿床的成矿时间为141 Ma左右。对赣北、赣中和赣南地区的成岩成矿年龄进行对比,发现三地的成岩成矿事件在时间上具有连续性。结合区域构造演化历程,本文认为石门寺钨铜多金属矿形成于早白垩世时期的伸展减薄环境。In order to explore the tungsten enrichment mechanism and metallogenesis of the Shimensi tungsten-copper polymetallic deposit in the northern Jiangxi,in this study,we have carried out the Re-Os isotopic dating of molybdenites of the deposit.The results show that six molybdenite samples have model ages varying from 140.2 Ma to 142.5 Ma,with a weighted mean age of(141.37±0.84)Ma(MSWD=0.84)and an isochron age of(141.79±0.97)Ma(MSWD=1.10),which are consistent within the standard deviation range and can be used to represent the mineralization age of molybdenite.Thus,the mineralization age of this deposit is about 141 Ma.On the basis of the above,we have made further comparison of diagenetic and metallogenic ages of tungsten polymetallic deposits in the northern,central and southern Jiangxi,and found that the diagenetic and metallogenic events in the three regions have continuity in time.Combined with the regional tectonic evolution history,we have suggested that the Shimensi tungsten-copper polymetallic ore deposit was formed in an extensional and thinning environment during the Early Cretaceous.

关 键 词：石门寺钨铜多金属矿床 RE-OS同位素 成矿年龄 赣北、赣中和赣南 

分 类 号：P597.3[天文地球—地球化学]