新疆西准包古图斑岩型铜钼矿床地质特征及流体包裹体研究

Geological characteristics and fluid inclusion studies of the Baogutu porphyry copper deposit in west Junggar of Xinjiang

包古图斑岩型铜钼矿床位于新疆西准噶尔达拉布特过渡岛弧南部。区域构造主要以北东向为主,由一系列大断裂组成。包古图含矿岩体是一个岩性和岩相复杂的中性斑岩体。矿化类型主要为浸染状矿化、细脉状矿化及网脉状矿化,成矿作用划分出3个阶段。流体包裹体数据显示:均一温度从第Ⅰ阶段到第Ⅲ阶段逐渐降低,表明矿化从早到晚经历的是一个降温过程。流体密度为0.65～1.15 g/cm^3,估算成矿压力为126.0×10~5～950.1×10~ Pa,成矿深度为0.42～3.17 km,流体包裹体气相成分主要为CH_4、N_2、C_2H_4,液相主要为H_2O,并含少量CO_3^(2-)。

The Baoguto porphyry copper deposit locates in south of the Darbut magmatic arc of the western Junggar. The north-east regional structure mainly composed by a series of major faults. The Baogutu intrusion is an intermediate porphyry with several lithologies and lithofacies. Mineralization type is disseminated mineralization, veinlets and network mineralization. The ore-forming process can divided into three phases. Fluid inclusions data showed. homogenization temperatures from the first stage to the third stage gradually reduced, indicating that mineralization from early and late going through a cooling process. Fluid density 0.65 1.15 g/cm^3, estimates of mineralization pressure of 126.0 ×10^5 -950. 1× 105 Pa, and depth of 0.42 - 3.17 km, Gas fluid inclusions are mainly CH4 , N2 , C2H4 , mainly for liquid H2O, and contain a small amount of CO3^2-.