青海大场金矿田北缘灭格滩矿区土壤地球化学异常信息提取及找矿预测

Soil Geochemical Anomaly Information Extraction and Prospecting Prediction of the Miegetan Gold Deposit,Northern Segment of the Dachang Gold Mine,Qinghai Province

灭格滩矿区位于青海北巴颜喀拉造山带大场金矿田北缘。三叠系巴颜喀拉山群昌马河组砂板岩是矿区主要赋矿地层。矿区内构造发育,矿(化)体主要沿NW向构造破碎带分布,产状受破碎带控制。围岩蚀变主要有硅化、黄铁矿化、毒砂化、绢云母化等。1∶10 000土壤地球化学测量Au、As、Sb、Hg元素丰度明显偏高,异常明显,浓集中心突出,各元素异常套合较好,呈NW向带状分布。剖面上元素含量峰值与矿体位置对应良好,据此构建了地质-地球化学找矿模型,能有效指导隐伏矿体的找矿勘查工作。在综合分析矿区地质及土壤地球化学异常特征的基础上,圈定了找矿靶区和成矿远景区,可以为灭格滩金矿区乃至矿田核心区外围找矿勘查工作提供重要参考。

The Miegetan gold deposit is located in the north of the Dachang Gold Mine, north Bayan Har Orogen, Qinghai Province, China. The main ore-bearing strata are sandstone of the Triassic Bayan Har Mountain Group. With well developed thrust faults, the ore bodies are distributed along NW structural fractures, which control the occurrence. Hydrothermal alterations include silicification, pyrite, arsenopy- rite mineralization and sericitization. The results of soil geochemical survey for Au, As, Sb and Hg show the anomalies are obvious and have a prominent concentration center. All anomalies with a NW distribu- tion have a good registration. The peaks of content variation trend in the section correspond well with the orebodies. The prospecting model developed on this basis can thus direct the prospecting work. The pros- pecting target and metallogenetic prospective area are delineated according to the comprehensive analysis of the geological and soil geochemical characteristics of the Miegetan gold deposit to provide the reference for the Miegetan gold deposit even the periphery of core area in the Dachang Mine.