鸭绿江成矿带沙窝沟金矿地质特征及成因

Geological features and genesis of the Shawogou deposit in the Yalu River gold mineralization belt

沙窝沟金矿产于鸭绿江成矿带NE段 ,石柱子花岗闪长岩与辽河群盖县组地层接触带 ,周家屯—万宝NW向断裂带的西侧。区内已发现的数十条含金脉体严格受近EW、NE、NW向 3组断裂控制 ,在断裂交汇处脉体变宽 ,厚度变大 ,平面上呈串珠状分布 ,总体走向 310～ 34 0° ;所圈出的工业矿体呈板状、透镜状产出 ,具有分支复合现象。S、H、O同位素及稀土元素特征表明 ,成矿物质来源与石柱子花岗闪长岩密切相关 ,成矿热液以岩浆水为主。流体包裹体测试结果表明 ,成矿属中—高温、中偏低压 (成矿深度 4 30～ 4 38km)、弱还原的成矿环境 。

The Shawogou gold deposit occures in the contact region between Shizhuzi granodiorite and the strata of Gaixian fraction of Liaohe group in the north east of Yalu River mineralization belt, and by the west side of Zhoujiatun Wanbao NW strike fault belt.There are a few dozen gold bearing veins in the area,which strictly controlled by the nealy NW,NE,and EW strike faults. At the intersection of fault, veinbodies become wider and thicker, scatter as moniliform on plane,and the general trend is 310～340°.The outlined industrial orebodies occured in form of tabular and lens shaped, present the phenomenon of subsidiary compounding.The isotope of S,H,O and the characteristics of rare earth element indicate that the source of ore forming minerals are closly related to Shizhuzi granodiorites, and magmatic water is predominant in hydrothermal ore forming solutions.The test to fluid inclusions shows that the mineralization has medium high tempreture, midium low pressure (the depth of mineralizing is 4 30～4 38 km), and slightly reduction setting.The deposit belongs to the type of magmatic hydrothermal origin.