坦桑尼亚维多利亚湖金矿田典型金矿床成矿特征与矿床成因  

Metallogenic characteristics and genesis of typical gold deposits in Victoria Lake gold field in Tanzania

作　　者：彭俊[1] 白德胜[1] 祁东[1] 梁永安[1] 楚明春 PENG Jun;BAI Desheng;QI Dong;LIANG Yong’an;CHU Mingchun(No.2 Institute of Geological and Mineral Resources Survey of Henan,Zhengzhou 450001,He’nan,China)

机构地区：[1]河南省地质矿产勘查开发局第二地质矿产调查院,河南郑州450001

出　　处：《地质通报》2023年第8期1377-1389,共13页Geological Bulletin of China

基　　金：河南省财政地质勘查项目《坦桑尼亚维多利亚湖绿岩带金矿床成矿规律研究及资源潜力评价》(编号:豫地矿[2021]8号)。

摘　　要：坦桑尼亚维多利亚湖金矿田经历了复杂的构造变形、岩浆活动和成矿作用演化,形成了丰富的金矿产资源。通过对其中的典型金矿床地质特征、成矿流体来源和成矿时代等方面研究,探讨了矿床成因和金的沉淀机制。金矿床主要赋存在绿岩带地层单元中,含矿构造主要为与绿岩带走向大致相同的韧-脆性剪切带。金矿石中H_(2)O-CO_(2)型流体包裹体均一温度范围主要集中于300~400℃,盐度范围集中于14%~22%,成矿流体属中—高温、高盐度流体;成矿流体来源主要为岩浆水,在成矿过程中部分变质热液也参与其中。金矿床成矿时代为2710~2620 Ma,即为新太古代;矿床类型为受剪切带控制的中—高温热液金矿床。上述研究进展对非洲绿岩带内的金矿找矿勘查工作具有指导意义。The Victoria Lake gold field has experienced complex structural deformation,magmatic activity and mineralization evolution,forming rich gold resources.Based on the study of geological features of typical gold deposits,source of ore-forming fluid and ore-forming age of the Victoria Lake gold field in Tanzania,this paper explores the genesis of the deposit and the gold precipitation mechanism.The gold deposits are mainly hosted in the stratigraphic units of the greenstone belt,and the ore bearing structures are mainly ductile-brittle shear zones with roughly the same strike as the greenstone belt.The homogenization temperature range of H_(2)O-CO_(2) fluid inclusions in gold ores is mainly 300~400℃,and the salinity range is 14%~22%.The ore-forming fluid belongs to medium-high temperature and high salinity fluid;The source of ore-forming fluid is mainly magmatic water,and part of metamorphic hydrothermal fluid also participates in the ore-forming process.The mineralization age of the Lake Victoria gold deposit in Tanzania is 2700~2620 Ma,which is Archean;The deposit type is a medium-high temperature hydrothermal gold deposit controlled by shear belt.The above research progress is of certain theoretical guiding significance for the prospecting and exploration of gold deposits in the greenstone belt of Africa.

关 键 词：绿岩带金矿 矿床成因 维多利亚湖金矿田 坦桑尼亚 

分 类 号：P618.51[天文地球—矿床学]