地球化学块体理论在厄立特里亚铜资源潜力预测中的应用  

Application of Geochemical Block Method in the Potential Prediction of Copper Resources in Eritrea

作　　者：向文帅 姜军胜 赵凯 曾国平 Ermias Yohannes Tesfai Berhe XIANG Wen-Shuai;JIANG Jun-Sheng;ZHAO Kai;ZENG Guo-Ping;ERMIAS Yohannes;TESFAI Berhe(Wuhan Center,China Geological Survey(Geosciences Innovation Center of Central South China),Wuhan 430205,Hubei,China;Ertirea Geological Survey,Asmara P.O.Box 272,Eritrea;China-Africa Gesoscience Cooperation Center,Wuhan 430205,Hubei China)

机构地区：[1]中国地质调查局武汉地质调查中心(中南地质科技创新中心),湖北武汉430205 [2]厄立特里亚地质调查局,厄立特里亚阿斯马拉P.O.Box272 [3]中国-非洲地学合作中心,湖北武汉430205

出　　处：《华南地质》2024年第1期63-74,共12页South China Geology

基　　金：湖北省自然科学基金项目(2022CFB850);中国地质调查局项目(DD20230575,DD20221802,DD20190443)。

摘　　要：新元古代东非造山运动在厄立特里亚阿拉伯-努比亚地盾区形成了大面积出露的变质火山沉积岩系及相应的花岗质岩浆岩,与之相关的铜矿资源非常丰富。本文以厄立特里亚1∶100万水系沉积物地球化学数据样本为基础,应用地球化学块体理论,对该国铜资源潜力进行预测。厄立特里亚共圈定地球化学块体7个,地球化学区域异常5个,地球化学块体的铜元素异常下限值为28×10-6。根据不同成矿带内已知铜矿床的资源量推算各区块铜的成矿率,以1 km矿床勘探深度为准则预测各区块潜在铜金属量,估算出厄立特里亚潜在铜资源为930.76万吨。其中,5、6号铜地球化学块体可作为下一步铜矿勘查的重点区域,1、2、3、4、7号铜地球化学块体的找矿潜力也值得注意。The Neoproterozoic East African orogeny formed a large area of exposed metavolcanic sedimentary rock series and corresponding granitic magmatic rocks in the Arab-Nubian Shield,Eritrea,in which the copper resource is very rich.In this paper,1:1000000 stream sediment geochemical data in Eritrea was selected as the research object.Based on the theory of geochemical block method,we synthetically evaluated the Cu resource potential of Eritrea.The result of geochemical data shows that the value of geochemical anomaly threshold is 28×10-6.Seven geochemical blocks and five regional anomalies were delineated.According to the reserves of known deposits in different metallogenic belts,the mineral coefficient of Cu in each areawas calculated.The total copper tonnage and mineral resources in each area were calculated based on the exploration depth of the 1km.Thus,we inferred that the total copper tonnage in the 7 geochemical blocks and 5 regional geochemical anomalies of Eritrea(given a 1 km thickness of every rock mass)is 9.3076 million tons.Among them,geochemical blocks 5 and 6 should be used as the focus of the next step,and the exploration potential in geochemical blocks 1,2,3,4 and 7 should also be noted.

关 键 词：地球化学块体 铜矿 资源潜力预测 厄立特里亚 

分 类 号：P612[天文地球—矿床学] P632.3[天文地球—地质学]