黔北务正道地区青坪铝土矿成矿地质特征及找矿潜力

Metallogenic geological characteristics and prospecting potential of Qingping bauxite deposit in Wuzhengdao area,North Guizhou

青坪铝土矿位于黔北务正道地区栗园向斜,区内铝土矿体产于呈NE—SW向展布的栗园向斜北段扬起端及东翼二叠系下统大竹园组含矿岩系中上部,矿体呈层状、似层状产出,厚度变化较大,矿体产状与岩层产状基本一致。本文收集矿区及周边已实施的31个探矿工程(钻孔、探槽),通过含铝岩系厚度、矿体厚度沿走向和倾向变化进行对比并绘制矿区含铝岩系等厚曲线图综合分析后认为:铝土矿体在平面上总体具有由地表向深部、从北往南逐渐变薄的趋势,在栗园向斜北扬起端为含铝岩系厚度大且相对稳定,栗园向斜东翼、西翼存在2个含铝岩系厚度大的成矿区域,找矿潜力大,该向斜南部含铝岩系厚度逐渐变薄,铝土矿体尖灭,找矿潜力较差。

Qingping bauxite deposit is located at Liyuan syncline in the Wuzhengdao area,North Guizhou Province.The bauxite orebody in this area is located at the upper and middle end of the north section of Liyuan syncline and the ore-bearing rock series of Dazhuyuan Formation of the Lower Permian in the east wing.The orebodies are stratified and semi-stratified,and the thickness varies greatly,the occurrence of orebodies is basically consistent with that of rock strata.In this paper,31 exploration projects(drilling holes and trenches)that have been implemented in the mining area and its surrounding areas are collected and compared by the thickness of aluminum-bearing rock series and the thickness of ore bodies along the strike and dip direction,and the isothickness curve of aluminum-bearing rock series in the mining area is drawn.After the comprehensive analysis,it is concluded that in the plane the bauxite orebody gradually becomes thinner from the surface to the depth and from the north to south.In the north uplift end of Liyuan syncline,the thickness of aluminium-bearing rock series is large and relatively stable.In the east and west wing of Liyuan syncline,there are two ore-forming areas with large thickness of aluminium-bearing rock series,with a great prospecting potential.The thickness of the aluminum bearing rock series in the south part of the syncline gradually becomes thinner,and the bauxite ore body is pinched out,there is a poor prospecting potential.