桃江县板溪锑矿床地质特征及成矿构造分析

桃江县板溪锑矿,主要开采2号矿脉,它赋存在上元古界板溪群五强溪组上段,由中矿脉、东支脉和西盲脉组成,矿石矿物主要是辉锑矿,平均厚度0.40 m,平均品位Sb 25.48％,属燕山期中低温热液型锑矿床。矿区成矿构造V_2和V_(2-1)断裂,成矿前显张扭性,成矿期转化为压扭性质,西盲脉,则充填V_(2-2)断裂派生的“多”字型构造。它们为矿区富厚矿体提供了主要成矿空间,展示了构造与矿床的密切成生联系。

GEOLOGIC FEATURE AND METALLOTECTONIC ANALYSIS OF BANXI ANTIMONY ORE DEPOSIT,TAOJIANG COUNTY

Banxi antimony ore deposit in Taojiang county, in which the ore vein No. 2 is the major object of mining, occurs in the upper member of wuqiangxi Formation of Upper Proterozoic Banxi Group, composed of the Middle vein, East vein and the west concealed vein. The main ore mineral is stibnite. Its average thichness is 0.40m, and its average Sb grae is 25.48%. It belongs to Yanshanian meso-epithermal hydrothermal antimony ore deposit. The ore-forming structure--V_2 and V_(2-1) faults are of tensile-shear property premetallogenically and changed into compresso-shear property in the mineralization stage. The west concealed vein filles in the xi-type struc-tures derived from V_(2-2) fault. They provided the major ore-forming space for the rich and thich orebodies in the ore district, which demonstrated the close genetic connection of the deposit with the structure.