黑龙江磨石山铜多金属矿床流体包裹体研究

磨石山铜多金属矿床位于小兴安岭—张广才岭成矿带、磨石山—红星铜多金属矿集中区内。对该矿床主矿体含矿石英脉石英矿物的流体包裹体进行了岩相学、显微测温和单个包裹体气液相成分激光拉曼探针分析研究表明,流体包裹体类型分为Ⅰ型含CO2包裹体、Ⅱ型CO2包体及Ⅲ型气液两相包裹体,均一温度变化为205.9℃～297.6℃,流体盐度变化为2.2～9.2wt%(NaCl);该矿床成矿流体为一含CO2、中等盐度的NaCl--H2O--CO2体系流体。成矿流体的不混溶(沸腾)作用是铜、钼多金属矿化富集的重要因素。该矿床成矿压力为75～110MPa,成矿深度为2.5～3.7km,反映矿化形成于中等深度,矿床属中温岩浆热液矿床,成矿作用与晚侏罗世古太平洋板块的俯冲作用有关。

Study on fluid inclusions in Moshishan copper-polymetallic deposit of Heilongjiang

Moshishan copper--polymetallic deposit is located in Moshishan--Hongxing metallogenetic district belonging to Xiaoxinganling--Zhangguangcailing ore concentrated zone. The fluid inclusions in quartz mineral of orebearing quartz vein from major ore body were examined by means of petrography,microtemperature measurement and Raman microprobe of single fluid inclusion vapor-liquid phase. The study shows that there exist three types of fluid inclusions,including two types of carbon dioxide-bearing inclusions （type Ⅰ,Ⅱ）,and a vapor-liquid twophase inclusions （type Ⅲ）. The homogenization temperature is 205. 9 ℃ ～ 297. 6 ℃,salinity is 2. 2 ～ 9. 2 wt% （NaCl）,and the ore-forming fluid is a carbon dioxide-bearing NaCl--H2O--CO2 system with medium salinity. Immiscibility （boiling） of ore-forming fluid is an important factor of Cu--Mo polymetallic mineralization enrichment. The metallogenic pressure of ore deposit is 75 ～ 110 MPa and the mineralization depth is 2. 5 ～ 3. 7 km,which reflects the mineralization was formed in medium depth. The deposit belongs to middle temperature hydrothermal deposit,and the mineralization was related to the subduction of ancient Pacific Ocean Plate in Late Jurassic.