内蒙古乌拉特后旗查干花钼矿床地质特征及Re-Os测年  

Geological Characteristics and Re-Os Dating of the Chaganhua Molybdenum Deposit in Urad Rear Banner,Western Inner Mongolia

作　　者：蔡明海[1] 张志刚 屈文俊[3] 彭振安[1] 张诗启[1] 徐明[1] 陈艳[1] 王显彬[1] 

机构地区：[1]广西大学资源与冶金学院,广西南宁530004 [2]内蒙古自治区第一地质矿产勘查开发院,内蒙古呼和浩特010020 [3]国家地质实验测试中心,北京100037

出　　处：《地球学报》2011年第1期64-68,共5页Acta Geoscientica Sinica

基　　金：内蒙古自治区地质矿产勘查开发局"内蒙古自治区内生金属成矿规律及靶区筛选"项目(编号:ND2007004)资助

摘　　要：查干花钼矿是近年来在内蒙古西部中蒙边境地区新发现的一个具大型规模隐伏矿床,区内辉钼矿化呈浸染状、团块状、细脉状分布于中细粒二长花岗岩与古元古界宝音图群地层北东接触带部位,具斑岩型矿床特点。本文在对矿区矿化和蚀变特征初步研究的基础上,开展了辉钼矿Re-Os测年,获得模式年龄为(239.3±3.3)～(242.6±3.6)Ma,等时线年龄为(242.7±3.5)Ma,MSWD=0.77,187Os初始比值为-1±3ng/g,表明钼成矿时代为三叠纪,属印支早期构造-岩浆活动产物。研究认为,内蒙古西部宗乃山-沙拉扎山构造带内的查干花—查干德尔斯岩体周边为一钼多金属成矿区,并初步总结了该成矿区内钼多金属成矿特征及找矿标志。The Changanhua molybdenum deposit,a concealed porphyry molybdenum deposit newly discovered in western Inner Mongolia,contains large quantities of molybdenum resources.This ore deposit is characterized by disseminated,lumpy and veinlet molybdenite mineralizations hosted in the northeastern contact zone between medium-fine grained monzonitic granite and Paleoproterozoic Baoyintu Group.Re-Os isotopic dating of six samples from various ore bodies in the ore deposit yields model ages of（239.3±3.3）～（242.6±3.6）Ma,isochron age of（242.7±3.5）Ma,initial 187Os of-1±3 ng/g,and MSWD of 0.77,indicating that molybdenum mineralization took place in lower Triassic and was related to tectonomagmatic orogenic process in early Indosinian period.The Chaganhua-Chagandeersi granite in the Zongnaishan-Shalazashan structural belt of western Inner Mongolia is considered to be a molybdenum-polymetallic metallogenic area.Characteristics of molybdenum mineralization and ore-prospecting criteria in this area are also summarized in this paper.

关 键 词：矿床特征 RE-OS测年 查干花钼矿 内蒙古西部地区 

分 类 号：P611[天文地球—矿床学] P578.291[天文地球—地质学]