浙江省丽水市关塘—蛤湖地区重力场与地质矿产分布关系

Distribution relationship between gravitational field and mineral resource in Guantang-Gehu area of Lishui,Zhejiang

浙江省丽水市关塘―蛤湖地区位于江山―绍兴拼接带与余姚―丽水深断裂之间的变质基底隆起区,成矿地质条件较好。为研究区内基底构造形态、火山构造、隐伏岩体等基础地质问题,开展了1∶5万重力调查。重力成果表明,西岱―西溪―季岱梯级带为基底断陷与隆起区的界线,剩余重力正异常为基底隆起的反映,负异常为基底凹陷的反映。区内矿产分布与基底构造关系密切,变质热液型铅锌、多金属矿多分布在变质基底出露区,金银矿多位于基底浅覆盖区,基底凹陷区内多金属矿与侵入岩或火山构造有关。综合地质物化探资料,圈定5个成矿远景区,为区内地质找矿工作的部署提供了地球物理依据。

I.ying in side the metamorphic basement uplift area between Jiangshan Shaoxing suture Belt and Yuyao-Lishui deep fracture, Guantang-C-ehu area has relatively favorable metallogenic and geological condi- tions. The gravity survey at the scale of 1 ： 50000 is performed to research on the basic geological issues. such as basement structures and morphologies, volcanic structures, and concealed rock bodies in the area. The research findings indicat that Xidai-Xixi-Jidai gradient zone is the boundary line between basement fault depression and uplifted area. Positive residual gravity anomalies are reflection of basement uplift, while neg- ative anomalies are reflection of basement depression. The distribution of ore minerals in the area is closely occur in the metamorphic basement outcropped area, and the Au-Ag deposits in the basement shallow over lay area, and the polymetallic deposits（related to intrusive rock or volcanic structure） in basement depression