刚果(金)东北部太古宙绿岩型金矿地质特征及找矿方向

Geological characteristics and prospecting direction of greenstone type gold deposits in the Northeast Democratic Republic of Congo

绿岩型金矿是刚果(金)重要的金矿类型之一。刚果(金)东北部的金矿床以内生金矿为主,次为外生金矿,内生金矿中主要为构造控制的脉状金矿床。典型矿床为基巴里绿岩带中的基洛矿区,矿化主要发生在发生碳酸盐化岩石的片理、剪切带和褶皱裂隙中;其次为受片理控制的浸染状金矿床,主要位于基巴里绿岩带的摩托矿区,矿化通常与围岩的片理相一致,并发育碳酸盐化等蚀变。研究认为,金矿床中的金质主要来源于绿岩带,太古宙岩浆活动形成了金的第一次富集,后期绿片岩相变质作用和强烈的蚀变造成了金的活化,并最终沉淀在构造裂隙中成矿。文章还总结了金矿床的找矿标志,并为区域金矿勘查方法提出了建议。

Greenstone type gold deposit is one of the most important gold deposit types in Democratic Republic of Congo.In the northeast Democratic Republic of Congo this type can be divided into endogenetic gold deposit and exogenetic gold deposit and the former is dominant and mainly structure-control lode deposit.The Kilo deposit in Kibalian greenstone belt is the typical deposit of this type with mineralization mainly in the foliation and cracks of shear zone and folding fissure in the carbonized host rock.Then is the foliation-controlled disseminated gold deposits occurring mainly in carbonized rock in Moto mining area of Kibalian greenstone belt.The mineralization is generally concordant to schistosity or foliation of the country rock.Research and summary of characteristics of the regional and typical deposits reveals that gold of the deposits is mainly derived from the greenstone.Archean magmatism enriches the gold primarily and the regional green schist facies metamorphism and the intense alteration of wall rock remobilizes and enrich the gold into ore at last in structural fissures.On Basis of the above marks suggestions for gold prospecting in the area are put forward.