The Taipingdong gold deposit lies in the Xingren-Anlong gold belt of the Huijiabao gold district The research on fluid inclusions indicates that various types of fluid inclusions are formed in quartz-pyrite (stage I ), quartz-pyrite-arsenopyrite (stage H ) and quartz-calcite-realgar (stage HI), which include mainly liquid-rich two-phase inclusions, CO, inclusions, mono-phase aqueous inclusions and CO,-H2O inclusions, subordinate^ mono-phase organic vapor inclusions, and minor liquid-vapor organic inclusions are present in minerals of different stages. The homogenization temperature of the aqueous fluid inclusions decreases from stage I (200 ~ 260t), through stage H (180 - 240℃ ) to I (100 ~ 160℃). In quartz of stage I , CO2-H2O inclusions occasionally coexist with two-phase aqueous inclusions locally. The coexistence of two-phase aqueous inclusions with simultaneously trapped CO2 inclusions, monophase aqueous inclusions and C0,-H,0 inclusions, mono-phase organic vapor inclusions and liquid-vapor organic inclusions in quartz of stage II and the similar homogenization of two-phase aqueous and CO2-H2O inclusions suggests that the ore-forming fluid experienced fluid immiscibility between CO, and low-salinity water. This indicates that fluid immiscibility extensively took place at later stage. The immiscibility of ore-forming fluids between CO2 and low-salinity water caused Au mineralization in the Tai pingdong gold deposit during (he main mineralization stage.%太平洞金矿床是兴仁-安龙金矿带灰家堡金矿区的重要卡林型金矿之一.流体包裹体研究证明,石英-黄铁矿阶段(Ⅰ)、石英-黄铁矿-毒砂阶段(Ⅱ)、石英-方解石-雄黄阶段(Ⅲ)的包裹体类型丰富,以气液水两相包裹体、CO2-H2O包裹体和纯液相水包裹体为主,CO2两相包裹体、纯气相有机质包裹体和有机质-H2O包裹体次之,偶见气液有机质包裹体.由Ⅰ-Ⅱ→Ⅲ阶段,气液水包裹体均一温度(200 ～ 260℃→180～240℃→100～160℃)呈现逐渐降低的趋势.在Ⅰ阶段的石英中,只在局部偶见到CO2-H2O包裹体和气液两相水包裹体共生；在Ⅱ阶段的石英中,纯液相水包裹体、气液两相盐水包裹体、CO2-H2O包裹体、CO2包裹体及纯气相有机质包裹体共存,它们共生在同一平面中且气液两相盐水包裹体和CO2-H2O包裹体测温数据相差不大,说明当时捕获的是不均匀成矿流体,它是由含有机质的成矿流体经历了CO2-低盐度水的不混溶作用形成的.因而认为,太平洞金矿床中成矿早期流体不混溶作用不明显,主成矿阶段流体的不混溶作用是导致金矿质沉淀的重要原因.
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