陕西石梯钡矿床中流体包裹体特征及成因意义  

Characteristics of fluid inclusions in barite,witherite and barytocalcite from the Shiti barium deposit in southern Shaanxi and their genetic significance

作　　者：吴胜华[1,2] 刘家军[1,2] 柳振江[1,2] 翟德高[1,2] 要梅娟[1,2] 

机构地区：[1]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 [2]中国地质大学地球科学与资源学院,北京100083

出　　处：《中国地质》2010年第5期1469-1479,共11页Geology in China

基　　金：国家自然科学基金(40573032);国家重点基础研究发展规划(2006CB403500);高等学校学科创新引智计划(B07011);长江学者和教育部创新团队发展计划项目资助

摘　　要：陕西石梯重晶石-毒重石矿床产于南秦岭早古生代大型钡成矿带中。矿石类型有重晶石矿石、毒重石矿石、重晶石-毒重石混合矿石和钡解石矿石,但以重晶石矿石为主。经显微测温表明,重晶石中流体包裹体的均一温度范围为103.4～253.1℃(主峰值140～160℃),盐度范围为(0.35～10.73)wt%NaCleqv;毒重石中流体包裹体的均一温度范围为152.8～303.7℃(主峰值200～220℃),盐度范围为(0.18～9.73)wt%NaCleqv;钡解石中流体包裹体的均一温度范围为107.8～260.0℃(主峰值160～200℃),盐度范围为(0.71～8.41)wt%NaCleqv。经激光拉曼分析表明,在矿物流体包裹体的气相组成中,各矿物有一定差异:重晶石含一定量N2、H2S和CH4,毒重石含大量CO2和N2,而钡解石含有CO2、N2和CH4。成矿流体温度相对较高、富含CO2是形成毒重石的重要条件。The Shiti barite-witherite deposit of Shaanxi occurs in an early Paleozoic large Ba metallogenic belt of southern Qinling region.Barite,witherite,barite-witherite and barytocalcite constitute major ore types,with barite being the main ore.Microthermometry reveals that homogeneous temperatures and salinities of fluid inclusions in barite are from 103.4℃ to 253.1℃（main peak values 140～160℃） and from 0.35 wt%NaCl eqv.to 10.73wt%NaCl eqv.,homogeneous temperatures and salinities of fluid inclusions in witherite are from 152℃ to 303.7℃（main peak values 200～220℃） and from 0.18 wt%NaCl eqv.to 9.73wt%NaCl eqv.,and homogeneous temperatures and salinities of fluid inclusions in barytocalicite are from 107.8℃ to 260.0℃（main peak values 160～ 200℃） and from 0.71 wt%NaCl eqv to 8.41wt%NaCl eqv.,respectively.Laser Raman analyses show that gas phase compositions of fluid inclusions in these minerals are somewhat different：barite contains some N2,H2S and CH4,witherite contains abundant CO2 and N2,and barytocalicite contains some CO2,N2 and CH4.The relatively high temperature and abundant CO2 in fluids constitute conditions for witherite formation.

关 键 词：重晶石-毒重石矿床 流体包裹体 石梯 陕西 

分 类 号：P578.71[天文地球—矿物学]