蒙古国西部乌兰乌拉钨矿床地质特征及找矿方向

Geological Characteristics and Prospecting Direction of Ulan Ulla Tungsten Deposit in the Western Part of Mongolia Republic

针对蒙古国西部乌兰乌拉矿区及矿床的地质特征进行了研究。乌兰乌拉钨矿床位于阿尔泰被动大陆边缘带与科布多浊积岩带接合部的乌列盖蛇绿岩带内。矿体主要以黑钨矿-石英脉形式产出于晚三叠-早侏罗世的侵入杂岩体中,受NE向断裂构造控制,呈不规则脉状、似层状,成群、成带出现。围岩蚀变主要有硅化、云英岩化、钾化及碳酸盐化等,其中硅化、云英岩化与钨矿化关系密切。初步分析认为,乌兰乌拉钨矿床成因类型为黑钨矿-石英脉型矿床,成矿地质条件优越,找矿潜力巨大。

Ulan Ulla Tungsten Deposit is located in the Olgii Ophiolite Belt at the junction of Altai Passive Continental Margin and Khovd Turbidite Belt.The ore body occurs in the Late Triassic early Jurassic intrusive complex and is strictly controlled by NE trending fault structure.Tungsten ore bodies are irregular vein-like and layered,often in groups and zones.The ore metal minerals are mainly wolframite,followed by pyrite,chalcopyrite,molybdenite,etc.;the non-metal minerals are mainly quartz and muscovite.The ore-forming age of the deposit is from Late Triassic to early Jurassic of Yanshanian Period.The ore-bearing hydrothermal fluid comes from the intermediate acid intrusive body,and the ore-forming is mainly by filling.The genesis of the deposit is Greisen Type W-bearing Quartz Vein Deposit.The second vein group and the third vein group of the mining area can be regarded as the focus of the next prospecting direction.