赣南崇义地区茅坪钨锡矿床铼-锇同位素定年及其地质意义  

Re-Os Isotopic Dating of Molybdenite from the Maoping Tungsten-Tin Deposit in Chongyi County of Southern Jiangxi Province andIts Geological Significance

作　　者：曾载淋[1,2] 张永忠[2] 朱祥培[2] 陈郑辉[3,4] 王成辉[1] 屈文俊[5] 

机构地区：[1]中国地质科学院,北京100037 [2]江西省地质矿产勘查开发局赣南地质调查大队,江西赣州341000 [3]中国地质科学院矿产资源研究所,北京100037 [4]中国地质大学(北京),北京100083 [5]国家地质实验测试中心,北京100037

出　　处：《岩矿测试》2009年第3期209-214,共6页Rock and Mineral Analysis

基　　金：国家科技支撑计划项目资助(2006BAB01B03);国土资源地质大调查项目资助(1212010813062);江西省地勘局科研项目资助(赣地矿字[2008]52号)

摘　　要：茅坪钨锡矿床位于南岭成矿带东段,位于崇(义)—(大)余—(上)犹钨多金属矿矿集区西华山—杨眉寺区段中北部的天门山—红桃岭矿田,为天门山岩体向北倾伏延伸的前锋部位;矿区钨锡矿化类型主要有云英岩型和石英脉型两种。文章选取云英岩型矿体及上部石英脉型钨矿体中与黑钨矿共生的辉钼矿7件,进行Re-Os等时线年龄测定,得到其模式年龄为(141.4±2.2)Ma～(158.2±2.2)Ma,其中云英型钨锡矿体中辉钼矿等时线年龄为(156.8±3.9)Ma,成矿时代为中侏罗世,对应于燕山早期第二阶段;从云英岩矿体中样品模式年龄为(150.7±2.4)Ma～(158.2±2.2)Ma,石英脉型矿体中样品模式年龄为(141.4±2.2)Ma～(151.0±2.4)Ma。分析石英脉型矿体紧随但略晚于云英岩型钨锡矿体成矿,并结合矿田内取得的同位素年龄数据,探讨了矿田成岩成矿时代及时差,推断天门山岩体可能为多次成岩成矿的复杂式岩体,其成矿时代跨度为133～156Ma。The Chongyi-Dayu-S Maoping tungsten-tin deposit is located in the eastern section of Nanling metallogenic belt, the hangyou tungsten polymetallic ore concentration area and at the front part of the Tianmenshan rock mass extension with a north trend. Greisen and the quartz vein are the main tungsten-tin mineralization types in the mine area. Seven molybdenite samples from greisen ore body and quartz vein tungsten ore body associated with black tungsten ore were chosen for Re-Os isotopic dating and model age of （141.4 ±2.2） Ma - （158.2 ±2.2） Ma were obtained. The isochrone age of molybdenites from greisen type tungsten-tin ore body is （ 156.8±3.9） Ma, which indicates that its mineralogenetic epoch is at the Middle Jurassic, corresponds to the second stage of early Yanshanian period. And the model age for the samples from greisen ore body and from quartz vein ore body are （150.7 ±2.4） Ma -（158.2 ±2.2） Ma and （141.4 ±2.2） Ma - （151.0 ±2.4） Ma respectively, which indicates that the mineralization time of the quartz vein ore body is slightly earlier than that of greisen ore body. Based on the other isotopic dating data from the mine area, the minerogenetic epoch and the time differences for different ore bodies were discussed and a conclusion that the Tiamnenshan rock body is a compound complex rock body undergoing repeated ore-forming processes and with minerogenetic epoch span of 133 - 156 Ma was deduced.

关 键 词：茅坪钨锡矿床 辉钼矿 铼-锇同位素定年 成矿时代 

分 类 号：P597.3[天文地球—地球化学] P578.291[天文地球—地质学]