吉林长安堡钼铜矿床含矿岩体锆石U-Pb年龄和Hf同位素组成  

Zircon U-Pb ages and Hf isotope composition of the ore-bearing intrusion from the Chang'anpu Mo-Cu Deposit,Jilin Province

作　　者：周毅[1,2] 松权衡[3] 张勇[4] 王岩[4] 于城 

机构地区：[1]吉林大学地球科学学院 [2]国土资源实物地质资料中心 [3]吉林省地质矿产勘查开发局 [4]中国地质科学院矿产资源研究所国土资源部成矿作用与资源评价重点实验室 [5]吉林省地质调查院

出　　处：《黄金》2016年第7期25-29,共5页Gold

基　　金：国土资源部成矿作用与资源评价重点实验室开放基金项目(ZS1404);中央级公益性科研院所基本科研业务费专项资金项目(K1503);中国地质调查局项目(12120113092700;12120114051401;121201103000150003)

摘　　要：长安堡斑岩型钼铜矿床是吉林中部地区新发现的一座大型矿床，钼铜矿化与二长花岗岩密切相关。在矿床地质特征研究的基础上，对含矿二长花岗岩开展了锆石 LA－ICP－MS U－Pb年代学和Hf同位素研究，获得了二长花岗岩成岩年龄为170．2 Ma ±0．6 Ma，与已获得的辉钼矿Re－Os加权平均年龄（168．0 Ma ±1．0 Ma）在误差范围内基本一致，表明长安堡钼铜矿床成岩成矿作用发生于中侏罗世。锆石εHf（t）值为7．0～10．08，Hf单阶段模式年龄（tDM1）为417～542 Ma，二阶段模式年龄（tDM2）为570～768 Ma，揭示矿区二长花岗岩源自新元古代亏损地幔中增生的新生地壳。成岩成矿作用与古太平洋板块俯冲作用相关。Chang＇anpu Mo-Cu deposit is a large-scale porphyry deposit newly discovered in central Jilin Prov-ince.The mineralization of copper and molybdenum is closely related to monzogranite.On the basis of research on de-posit geological features,the paper conducted a study of LA-ICP-MS zircon U-Pb dating combined with a Hf iso-tope analysis.The analysis results show that the zircon U-Pb ages of the monzogranite is 170.2 Ma ±0.6 Ma,which is consistent with the previous molybdenite Re-Os weighted mean age （168.0 Ma ±1.0 Ma） within error.It is indi-cated that the Chang＇anpu Mo-Cu deposit was formed in the Middle Jurassic.TheεHf （ t） value of the zircon is 7.0 to 10.08.The Hf single and two stage mode ages are 417 Ma to 542 Ma and 570 Ma to 768 Ma respectively.These data imply that the monzogranite in the mineralization zone originated from the growing juvenile crust in the depleted mantle in Neoproterozoic.Considering the regional tectonic background,the paper thinks that the magmatism and mineraliza-tion are probably related to subduction of the paleo-Pacific Plate.

关 键 词：LA-ICP-MS锆石U-PB测年 Hf 同位素测年 长安堡钼铜矿床 吉林中部 

分 类 号：TD11[矿业工程—矿山地质测量] P618.4[天文地球—矿床学]