中非铜钴成矿带地质特征与找矿前景分析  

Analysis on geological characteristics and prospecting potential of the Central African Cu-Co metallogenic belt

作　　者：孙凯 张航 卢宜冠 邱磊 何胜飞 任军平 许康康 刘晓阳 SUN Kai;ZHANG Hang;LU Yiguan;QIU Lei;HE Shengfei;REN Junping;XU Kangkang;LIU Xiaoyang(Tianjin Center,China Geological Survey,Tianjin 300170,China;School of Earth Science and Resources,China University of Geosciences(Beijing),Beijing 100083,China;Eastern and Southern Africa Geosciences Cooperation Research Center,CGS,Tianjin 300170,China)

机构地区：[1]中国地质调查局天津地质调查中心,天津300170 [2]中国地质大学(北京)地球科学与资源学院,北京100083 [3]中国地质调查局东部南部非洲地学合作研究中心,天津300170

出　　处：《中国地质》2022年第1期103-120,共18页Geology in China

基　　金：中国地质调查局项目(DD20190439、1212011220910);国家重点研发计划(2021YFC2901804)联合资助。

摘　　要：【研究目的】横跨刚果(金)和赞比亚边境地区的中非铜钴成矿带是世界上著名的沉积岩层控型铜钴成矿带,是全球第三大铜产地和第一大钴产地,然而其成矿规律和成矿潜力仍不明朗。【研究方法】本文通过对中非铜钴成矿带地质背景、构造演化与成矿、矿床时空分布规律、矿床模型等方面的研究,选择地层、构造、地球化学、遥感蚀变等与成矿密切相关的地质要素图层,采用模糊证据权法圈出32个铜(钴)远景区。依据成矿后验概率计算了在不同概率下每个远景区未发现矿床数量。【研究结果】结合吨位-品位模型所开展的蒙特卡洛模拟表明,该地区未发现的铜资源量平均估计为2.88亿t,钴资源量平均估计为1992万t。【结论】中非铜钴成矿带复杂的演化历史形成了该地区沉积成矿、热液成矿、表生富集等多种成矿作用的叠加,铜(钴)成矿作用贯穿成矿带演化过程,成矿作用与地层和构造密切相关。其中,刚果(金)利卡西-科卢韦齐地区可能存在很好的找矿前景。[Objective]The Central African copper-cobalt metallogenic belt which straddles the border area between the Democratic Republic of the Congo(DRC) and Zambia, is the world’s most famous sediment-hosted stratabound copper-cobalt metallogenic belt. It is the world’s third-largest copper and first-largest cobalt producer, but its mineralization pattern and potential are still unclear. [Methods]In this paper, the geological setting, tectonic evolution and mineralization, temporal-spatial distribution rules of deposits, deposit models of the Central African copper-cobalt metallogenic belt were studied. 32 copper(cobalt) prospective areas were delineated by applying the fuzzy weight of evidence method with stratigraphic, tectonic, geochemical, remote sensing alteration and other geological elements that are closely related to mineralization. The number of undiscovered deposits in each prospective area was calculated based on the posterior probability of mineralization at different probabilities. [Results]Monte Carlo simulation combined with the tonnage-grade model indicate that the average undiscovered copper resource in this area is estimated to be 288 million tons and the average cobalt resource is estimated to be 19.92 million tons, respectively. [Conclusions]The complex evolutionary history of the Central African copper and cobalt metallogenic belt has resulted in the superposition of multiple metallogenic interactions such as sedimentary mineralization, hydrothermal mineralization and epigenetic enrichment in this region,with copper(cobalt) mineralization running through the evolution of the belt and mineralization closely related to stratigraphy and tectonics. In particular, the Likasi-Kolwezi area of the Democratic Republic of the Congo may have good prospects for mineralization.

关 键 词：铜钴矿 地质特征 找矿前景 非洲中部 地质调查工程 

分 类 号：P618.41[天文地球—矿床学] P681.62[天文地球—地质学]