湘南骑田岭芙蓉锡矿田流体包裹体特征和成分  

Characteristics and composition of fluid inclusions in Furong tin orefield,Qitinling area,South Hunan Province

作　　者：李桃叶[1] 刘家齐[1] 

机构地区：[1]宜昌地质矿产研究所,湖北宜昌443003

出　　处：《华南地质与矿产》2005年第3期44-49,共6页Geology and Mineral Resources of South China

摘　　要：芙蓉矿田流体包裹体研究表明,从成岩到主成矿阶段的有关矿物中,以富含CO2包裹体和出现大量高盐度包裹体为特征.从成矿作用早期到主成矿期直至成矿期后无矿石英脉,其均一温度由290～560℃逐渐降至230～450℃(主成矿期),无矿石英脉仅为150～220℃;其盐度w(NaCl)相应由47%～67%逐渐降至10%～57%,最后为4%～6%.似伟晶岩石英、矽卡岩的透辉石中群体包裹体的气、液相成分研究表明,成矿流体的主要成分是H2O(w(H2O)=66.34%～71.54%)和CO2(w(CO2)=28.33%～33.5%),其CO2含量比大脉型W,Sn矿床中的CO2含量高出一个数量级,同时远远高于大厂锡石-硫化物型锡矿床中的CO2含量;溶液中的阳离子主要是Na+,其次是K,Na+/K+=16;阴离子中Cl-很高,其Cl-/H2O比值较大脉型W,Sn矿床高一个数量级以上,但与大厂锡石-硫化物型锡矿床中的Cl-/H2O比值较接近.似伟晶岩石英、矽卡岩的透辉石和锡石-硫化物石英中单个包裹体的激光拉曼光谱分析同样表明,其成矿流体主要是H2O,其次是CO2,液相中x(H2O)= 66.9%～89.1%, x(CO2)=8.1%～15.5%.Study on fluid inclusions within minerals from Furong orefield indicates that the fluid inclusions formed from diagenetic stage to the main mineralization epoch are characterized by high salinity and rich in CO2. Homogeneous temperatures of the inclusions changed slowly with mineralization process from 290～560℃ （ early mineralization ） to 230～450℃ （ main mineralization ） to 150～220℃ （post-mineralization quartz veins）, the salinity w（NaCl） declined correspondingly from 47%～67% to 10%～57% to 4%～6%. Study on the gas and liquid compositions of colony inclusions within quartz of pegmatoid and diopside of skarn show that the mineralization fluids consist mainly of H2O （66.34%～71.54%） and CO2 （28.33%～33.5%） ,especially the CO2 content is one magnitude higher than that of the large-vein type W-Sn deposit and much higher than that of cassiterite-sulfide orebodies in Dachang orefield; cations in inclusions are mainly Na and K with Na^＋/K^＋ = 16; anions are dominated by Cl^- with Cl^-/H2O ratios one magnitude higher than that of the large-vein W-Sn deposit and similar to that of the cassiterite - sulfide orebodies in Dachang deposit. Laser Laman spectral analyses of inclusions within quartz from the pegmatiod and cassiterite-sulfide quartz as well as diopside from the skam also indicate that the mineralization fluids consist mainly of H2O（66.9%～89%） and CO2（8.1%～15.5%）.

关 键 词：流体包裹体 包裹体成分 芙蓉锡矿 湘南骑田岭 

分 类 号：P618.44[天文地球—矿床学]