甘肃省根沙塘地区地球化学、地球物理特征及找矿模型  

Geochemical and geophysical characteristics and prospecting model of Genshatang area,Gansu Province

作　　者：严康 韦乐乐[2] 张建鹏 李康宁 火兴达 Yan Kang;Wei Lele;Zhang Jianpeng;Li Kangning;Huo Xingda(The Third Institute of Geological and Minerals Exploration,Gansu Provincial Bureau of Geology and Minerals Exploration and Development;School of Jewelry,Shaanxi Institute of International Trade&Commerce,Gemological Experimental Teaching Demonstration Center of Shaanxi Province)

机构地区：[1]甘肃省地质矿产勘查开发局第三地质矿产勘查院,730050 [2]陕西国际商贸学院珠宝学院,陕西省宝石教学示范中心

出　　处：《黄金》2020年第8期8-12,30,共6页Gold

基　　金：国家重点研发计划项目(2017YFC0601506);中国地质调查局项目(121201004000160901);甘肃省财政厅项目(甘资财[2019]27号)。

摘　　要：根沙塘地区位于夏河—合作断裂以北的中秦岭金铜铅锌钨钼多金属成矿带,地质构造复杂,成矿条件优越。1∶5万水系沉积物综合异常以Ag、Au、As等元素异常为主,套合好,且具分带性,通过路线踏勘对综合异常进行查证,发现了铅锌银矿(化)体,该矿(化)体明显受美武岩体与围岩接触带、北北西向层间断裂控制,与硅化、电气石化、孔雀石化、方铅矿化、闪锌矿化、辉银矿化等密切相关;基岩光谱曲线在矿(化)体附近呈单峰,指示矿(化)体的存在;矿(化)体的磁化率多小于20×10^-5 SI(κ),其磁化率较围岩弱,并表现为负磁异常特征。据此建立了研究区找矿模型,经查证,初步圈定1条金矿(化)体和1条铅锌银多金属矿(化)体。因此,该找矿模型可有效指导研究区进一步找矿。With complex geological structure and favorable ore-forming conditions,the Genshatang area of Gansu Province is located in the middle Qinling copper-gold-lead-zinc-tungsten-molybdenum polymetallic metallo-genic belt north Xiahe-Hezuo fault.1∶50000 stream sediment comprehensive anomaly is dominated by Ag,Au,As element anomalies with good fitting and obvious zonation.Based on the investigation of route reconnaissance for comprehensive anomaly,the lead-zinc-silver ore(mineralized)bodies are found to be evidently controlled by contact zone between Meiwu rock mass and wall rock,NNW-trending interlayer fracture,and closely related to silicification,tourmalinization,malachitization,gelenitization,sphaleritization and argentization.The bedrock spectral curve is presented as singlet peak near ore(mineralized)bodies,indicating the existence of ore(mineralized)bodies.The magnetic susceptibility of ore(mineralized)bodies are generally below 20×10^-5 SI(κ),the magnetic susceptibility is weaker in ore(mineralized)bodies than in wall rocks and displays characteristics of negative magnetic anomaly.Based on above investigation and study,prospecting model of the study area is established and through verification delineates 1 gold ore(mineralized)body and 1 lead-zinc-silver polymetallic ore(mineralized)body.The prospecting model can effectively guide further prospecting in study area.

关 键 词：地球化学特征 地球物理特征 找矿模型 矿(化)体 根沙塘地区 

分 类 号：TD15[矿业工程—矿山地质测量] P612[天文地球—矿床学]