延边刺猬沟金矿床流体包裹体特征及其找矿意义

刺猬沟矿床是中国东北地区典型的低硫化型浅成低温热液型金矿。为确定该矿床的成矿物理化学条件及形成深度，对不同标高的同一条含矿石英脉中的流体包裹体开展了显微测温和激光拉曼光谱分析。结果表明，含金石英--方解石脉中的石英与方解石主要发育气液两相及少量富液相包裹体，包裹体均一温度变化范围为112. 2 ℃ ～ 377. 7 ℃，集中在200 ℃ ～ 240 ℃，盐度( w ( NaCl) ) 为0. 18% ～ 10. 87%，平均值为3. 43%，成矿流体密度为0. 57 g /cm3 ～ 1. 00 g /cm3，平均值为0. 89 g /cm3。结合包裹体气相组分的激光拉曼光谱分析认为，成矿流体属低温、低盐度、低密度的NaCl --H2O ( --CO2 ) 体系。根据包裹体测温结果，估算出该矿床的成矿压力为7. 99 ～ 37. 89 MPa，平均值为14. 92 MPa，对应的成矿深度为0. 27 ～ 1. 26 km，平均值为0. 50 km。与国内外同类矿床的对比研究表明，该矿床剥蚀深度较小，深部仍具有一定的找矿远景。

Characteristics of fluid inclusions and its significance for ore prospecting of the Ciweigou gold deposit in Yanbian Region

The Ciweigou gold deposit is one of typical low-sulphidation epithermal gold deposits in NE China． In order to determine its physical and chemical conditions and ore-forming depth，the microthermometric and laser raman spectrum analysis of fluid inclusions in the quartz and calcite from the same auriferous quartz-calcite vein in different levels are carried out． There are major gas-liquid two-phase and small amount of liquid phase fluid inclusions in auriferous quartz-calcite vein． The homogenization temperature of the two-phase inclusions ranges from 112. 2 ℃ to 377. 7 ℃ and mainly from 200 ℃ to 240 ℃; the salinity ranges from 0. 18%NaCl to 10. 87%NaCl， and the average value is 3. 43%NaCl; the density changes from 0. 57g /cm3 to 1. 00 g /cm3 and the average is 0. 89 g /cm3 ． Together with the Raman spectra of gas phase in fluid inclusions，characteristics of the fluid inclusions show that the ore-forming fluid belongs to NaCl-H2O ( CO2 ) hydrothermal system with low temperature，salinity and density． According to the microthermometric data，the value of ore-forming pressure can be estimated from 7. 99 to 37. 89 MPa and the mean value is 14. 92 MPa． The depth of the mineralization is from 0. 27 to 1. 26 km，averaging 0. 50 km． Based on the comparision between the Ciweigou deposit with other epithermal gold deposits，it can be concluded that the small denudation depth of the Ciweigou deposit demonstrates the preferable ore prospecting in this deposits．