河南汤家坪钼矿床流体成矿作用研究  

Hydrothermal metallogeny of the Tangjiaping molybdenum deposit,Henan Province

作　　者：杨艳[1,2,3] 张静[2] 刘家军[2] 孙亚莉[1] 李晶[1,3] 杨泽强[4] 

机构地区：[1]中国科学院广州地球化学研究所成矿动力学重点实验室,广东广州510640 [2]中国地质大学地质过程与矿产资源国家重点实验室,北京100083 [3]中国科学院研究生院,北京100049 [4]河南省地质矿产勘查开发局第三地质调查队,河南信阳464000

出　　处：《中国地质》2008年第6期1240-1249,共10页Geology in China

基　　金：国家重点基础研究发展计划“973”项目(2006CB403506,2006CB403508);国家自然科学基金项目(40502012);地质过程与矿产资源国家重点实验室开放基金项目(GPMR200641)资助

摘　　要：汤家坪大型斑岩型钼矿床位于大别造山带。对流体包裹体的岩相学、显微测温及激光拉曼显微探针分析表明,汤家坪钼矿床的流体包裹体可划分为富(含)CO2包裹体、水溶液包裹体和含子晶包裹体3类;均一温度集中在126.7～472.1℃,盐度集中在(0.18～14.21)wt%和(33.10～54.37)wt%,密度为0.38～1.21g/cm3;子矿物含石盐及金属硫化物等。从矿体中心向外围,流体包裹体的温度、盐度有逐渐变小的趋势;从成矿早阶段到晚阶段,由高盐度低密度岩浆流体逐渐变为低盐度低密度流体,压力逐渐变小,深度变浅。辉钼矿的Re-Os模式年龄集中在113～118Ma,表明成矿略晚于母岩岩体的成岩时代,其成岩成矿的构造背景为华北与扬子板块碰撞造山晚期的伸展构造体制。The Tangjiaping Mo deposit in Henan Province is located in the Dabie orogenic belt. In quartz three types of fluid inclusions can be observed, namely CO2-rich （bearing） fluid inclusions, aqueous solution fluid inclusions and daughter-crystal-bearing fluid inclusions, based on the petrography, microthermometric measurement and Laser Raman microprobe analysis. The homogenization temperatures vary from 126.7℃ to 472.1℃, the calculated fluid salinities cluster in two ranges, i.e., （0.18-14.21） wt% NaCl.eqv and （33.10-54.37） wt% NaCl.eqv, with densities changing from 0.38 to 1.21 g/cm^3. Daughter minerals, mainly halite and metallic sulfide, can be recognized in fluid inclusions. The homogenization temperature and salinity of fluid inclusions reduce gradually outward from the center of ore-forming porphyry system. From early to late the fluid system evolved from and high temperature and high salinity to low temperature, and low salinity; and the trapped pressure reduced, indicating the mineralization depth became shallower gently. The Re-Os isotopic model ages of molybdenite are between 113 Ma and 118 Ma, about 10 Ma later than the crystalline age of the Tangjiaping granite porphyry. The ore-system was formed in waning stage extension setting of the inter-continental collision between Yangtze Block and North China Block.

关 键 词：流体包裹体 成矿流体 斑岩钼矿 汤家坪 

分 类 号：P618.65[天文地球—矿床学]