西天山博故图金矿床地质特征和找矿预测

博故图金矿床位于西天山石炭纪—二叠纪裂谷带中,其矿体赋存于构造破碎带内的大哈拉军山组火山碎屑岩、石英钠长斑岩及辉绿岩中。矿体受东西向基底断裂和北西向次级张扭性断裂带控制,对围岩没有选择性。与金矿化紧密相关的蚀变类型为硅化、黄铁矿化、毒砂矿化、泥化、绿泥石化。依据火试金分析结果圈定金矿体42条,矿体长45~1050 m,斜深34~670 m,平均厚度1.31~9.49 m,最大35.2 m,平均品位1.2~3.46×10-6,最高品位40×10-6,矿床平均品位2.01×10-6,金资源量(控制+探明+推测)达大型,矿床类型为浅成低温热液型金矿。金矿带上发育金、砷、银、钼等元素异常,矿体位于激电高极化率异常梯度带上,物、化探综合勘查成果显示Ⅰ号金矿带及其外围仍有很大找金潜力。

Geological characteristics and ore prediction of the Bogutu gold deposit in West Tian Shan

The Bogutu gold deposit is located in a Carboniferous - Permian rift zone, the West Tian Shan of Xinjiang, with orebodies occuring in quartz albite porphyry, Dahalajunshan Formation volcanic clastic rock and diabase within a fracture zone. The ore bodies are controlled by EW trending basement faults and secondary transextensionnal faults without dominant hosting rock. The alteration types closely related to gold mineralzation include silicification, pyritization, arsenopyritization, argillation, and chloritization. Totally 42 gold orebodies are delineated by fire assay results, which are 45-1050 m long, inclined deep 34-670 m, with average thickness 1.44- 35.2 m, average grade 1.2-3.46 x 10-6, largest grade 40×10-6, and average grade 2.01×10-6. The gold reserves and resource ( proven+indicated+inferred) of this deposit approach to a large scale (Au>20t). It is an epithermal gold deposit, where Au, As, and Mo anomalies are present within the gold mineralization zone, and gold orebodies occur in the gradient belts of high chargeability IP anomalies. The results of comprehensive geochemical-geophysical surveys show that the ore zone No. I and its surroundings have a great potential of gold resources.