坦桑尼亚西嘎山地区金矿床地质特征及找矿方向

Geological characteristics of gold deposit in Siga Hills,Tanzania and its prospecting direction

西嘎山(Siga Hills)地区位于维多利亚湖南部绿岩带上,该地区金矿床大多属绿岩带条带状铁建造(BIF)型金矿,金矿床赋存于条带状铁建造(BIF)中,矿体受"岩性+构造"双重控制。磁法测量显示马黑加矿区M1、M2、M3三条磁异常带,异常由条带状含铁建造和金矿体共同引起;土壤地球化学测量显示Au与As、Sb具有显著相关性。综合对比区域金矿信息,提出马黑加金矿化带南北延长线及其东部与花岗岩接触带、西嘎山南北走向带、西嘎山与马黑加之间等3个区域为今后西嘎山地区的找矿方向。

Siga Hills is located in the greenstone belt of southern Victoria Lake,and most gold deposits in this area are belonging to typical greenstone belts BIF.The gold deposit occurs in the banded iron formation,and the gold bodies are exactly controlled by both rocks and structures.The magnetic survey shows that there are three magnetism anomaly belts（M1,M2 and M3） in Maheiga gold deposit,which caused by BIF and gold mineralization.Soil geochemical survey expresses that the element Au has a relationship with As and Sb.Comparing with the information of gold deposits in this region,the authors proposed three areas as the prospecting direction in Siga Hills,including N-S extended line of Maheiga gold mineralization belt and the contact zone with granite in the east,the N-S belt of Siga Hills and the area between Siga Hills and Maheiga.