湖南宜章界牌岭锡多金属矿床地质特征及成因浅析

Geological Characteristic and Metallogeny of Jiepailing Tin Polymetallic Deposit in Yizhang,South Hunan Province

界牌岭矿区出露的地层主要为石炭系,白垩系零星分布。石磴子组不纯灰岩化学性质活泼,同时地层中W,Sn,Be,Pb,Zn成矿元素含量高。界牌岭背斜控制了区内的总体构造格架,断裂构造很发育,其中近南北向断层是区内的控岩导矿构造,它所派生的次一级断裂控制着区内的锡铅锌矿体。区内仅出露燕山晚期的花岗斑岩。围岩蚀变主要有云母化、黄玉化、云英岩化、萤石化。锡铅锌矿体隐伏在80m标高以下,浅部及地表有厚大的萤石矿体。该矿床形成于燕山晚期,经历了从高温-中温-低温的成矿阶段。

The stratum in the Jiepailing deposit is the Carboniferous series, and the stratum Cretaceous system can found on occasion. The impure limestone of Shidengzi formation is very active in geochemistry, and is rich in ore - forming elements of W, Sn, Be, Pb and Zn. The regional tectonic framework is controlled by Jiepailing anticline, and lots of faults, especially the N - S striking ones, constraint the distributing of tin - lead - zinc ore - body. There is only granite porphyry intruded in later Yanshanian found in this ore district. Micatization, topazization, greisenization and fluoritization are the main wall -rock alteration types. The tin - lead - zinc ore - body is found 80m under height mark, the above of which is the big thick fluorspar ore -body. This deposit formed in late Yanshanian, and has experienced from the high temperature, through mosotherm to hypothermal mineralization process.