一个巨大水晶中流体包裹体温压地球化学特征  

FLUID INCLUSION THERMOBAROGEOCHEMICAL FEATURES OF A MEGA-QUARTZ CRYSTAL

作　　者：刘家齐[1] 曾贻善[2] 

机构地区：[1]宜昌地质矿产研究所,宜昌443003 [2]北京大学地质学系,北京100871

出　　处：《华南地质与矿产》1999年第4期37-43,共7页Geology and Mineral Resources of South China

基　　金：国家自然科学基金项目"成矿流体中的羧酸"(No.49673193)的部分成果

摘　　要：对荡坪钨铍矿床晶洞中一长33cm的水晶不同横切块和同一切块的核部、中间过渡带和边缘环带包裹体的均一温度、盐度、密度和压力进行了研究,并用热爆法对群体包裹体成分和用激光拉曼探针对单个包裹体成分进行了测定。得知成矿作用温压地球化学条件演变规律,由晶体核部到其边缘环带,均一温度、盐度、压力逐渐降低,成矿溶液的密度递增;群体包裹体中的挥发组分主要是H_2O(占挥发分总量的96％～99％）,其次是CO_2、N_2、CO、CH_4和H_2等;单个包裹体中含有较多的有机质（C_1—C_6）和H_2S等。认为该钨铍矿床晶洞中水晶晶体是在相对开放体系中生长的,成矿早期的流体为岩浆期后气化高温热液,至成矿晚期逐渐演变为以大气降水为主的低温热液。Systematic study was carried out on the fluid inclusion thermobarogeochemical features of a mega-quartz crystal from the Dangping W-Be deposit,Jianxi,which shows that: (l)the homoge-nization temperature, salinity and pressure decrease, the density of ore-forming fluid increase regularly from core to margin of the crystal; (2)compositions of the gas phases in group inclusions are dominated by H2O(96% -99%) with a little CO2 ,CO,N2 ,CH4 ,H2 and so on; (3)there are some organic matter(C1-C6) within the individual inclusions. According to the thermobarogeochemical features,it is concluded that the crystal grew in an relatively open system and metallogenetic fluids of the early and late stage belong to post-magmatic high-temperature hydrothermal solution and low-temperature hydrothermal solution dominated by atmospheric water, respectively.

关 键 词：温压地球化学 水晶 钨铍矿床 液包体 钨矿床 

分 类 号：P618.72[天文地球—矿床学] P618.67[天文地球—地质学]