蒙古国西部阿尔泰地区苍希格钨矿床地质特征及成因探讨

苍希格钨矿床位于蒙古国西部阿尔泰钨-钼-铜-铅-锌-银多金属成矿带内.矿体围岩为中—上奥陶统巴赫留克组火山沉积岩及早泥盆世陶伊陶古什杂岩体,矿体呈脉状、似脉状、透镜状产出.围岩蚀变主要有硅化、云英岩化、萤石化、钠长石化、绿泥石化和碳酸盐化,其中硅化、云英岩化及萤石化与钨矿化关系密切.金属矿物主要为黑钨矿、白钨矿、磁黄铁矿、黄铜矿、黄铁矿、辉钼矿、辉铋矿、闪锌矿,矿物组合在水平和垂向上均具有一定的分带.初步分析认为,苍希格钨矿床为与海西期中酸性岩浆侵入有关的中高温热液石英脉型钨矿床.

GEOLOGICAL CHARACTERISTICS AND GENESIS OF THE TSUNKHEG TUNGSTEN DEPOSIT IN ALTAY AREA OF WESTERN MONGOLIA

The Tsunkheg tungsten deposit is located in the Altay W-Mo-Cu-Pb-Zn-Ag polymetallic metallogenic belt of western Mongolia. The wall rock of orebody is the volcanic sedimentary rock of Middle-Upper Ordovician Bakhriuk Formation and Early Devonian Taitaogushi complex, with the orebody occurred as vein, vein-like and lenticular forms. The wall rock alterations mainly include silicification, greisenization, fluoritization, albitization, chloritization and carbonatization, among which the former three are closely related to tungsten mineralization. The metallic minerals are mainly wolframite, scheelite, pyrrhotite, chalcopyrite, pyrite, molybdenite, bismuthinite and sphalerite, and the mineral assemblages have a certain zonation both horizontally and vertically. It is concluded from the preliminary analysis that the Tsunkheg tungsten deposit is of meso-hydrothermal quartz vein type, which is related to the intrusion of Hercynian acid-intermediate magma.