南秦岭蒲塘—毛堂地区隐爆杂岩体金矿特征、成矿模式及找矿方向

蒲塘—毛堂地区分布有大小不一的燕山期花岗斑岩体及角砾岩体构成的杂岩体,杂岩体岩石组合多样,来源于上地幔和下地壳深源物质。矿体、矿化体均受杂岩体岩筒特殊构造的控制,分布于岩筒接触带及其附近环状裂隙和放射状裂隙内,形态以带状和似筒状为主,延深大,产状陡。角砾型矿石金富集程度最高,且金矿化与黄铁矿化关系密切。根据本区角砾岩及矿体特征,建立了矿床的成矿模式。指出蒲塘矿区黑沟岩体的隐爆中心岩筒南接触带和围岩角砾岩南东部分,毛堂矿区北西向断层的上盘与北东向断层交叉位置是最有利的成矿部位。

Characteristics and metallogenic model of gold deposit within cryptoexplosive rock complex mass in Putang-Maotang region,southern Qinling belt and prospecting direction

The complex mass in Putang-Maotang region is composed of various sizes of Yanshanian porphyritic granite and breccia, which were derived from deep-seated materials in the upper mantle and lower crust. The mineralization and orebodies were controlled by pipe structure of the complex mass, and distributed within the pipe contact zone as well as the adjacent ring fissures and radial fissures mainly in ribbon and cylindrical pattern. The orebody has a steep occurrence and extends to the deep part. The intensive gold enrichment occurs in breccia and breccia gold mineralization is closely related with pyritization. Based on characteristics of the breccia and orebodies, the metallogenic model was constructed. Finally, the future prospecting direction was pointed out, i.e., southern contact zone of the pipe in Putang region with the pipe locating at the center of the cryptoexplosive complex, southeastern part of the surrounding area of the deposit in Putang region and the joint part in Maotang region where the NW-trending fault intersects NE-trending fault in the hanging wall.