西藏冈底斯地块北缘甲岗雪山钨-钼-铋-铜-金多金属矿床地质特征及成因初步研究

冈底斯地块南北缘是西藏重要的多金属成矿区之一，在该地块北部首次发现的甲岗钨-钼-铋-铜金多金属矿床是不同于其南部斑岩型铜多金属矿床的成矿新类型，该矿床的发现是藏北地区内生金属矿找矿的重要突破。目前，矿区内共发现规模大、品位高、易采易选的黑钨矿-辉钼矿-石英脉10余条。脉体赋存于区内白云母二长花岗岩的内外接触带，并以内带为主。通过对矿脉等的同位素、包裹体等的初步研究表明，矿床的形成与喜山早期碰撞型中酸性岩浆活动有密切联系，属典型的岩浆气液充填型黑钨矿-石英大脉型矿床。该矿床的发现对进一步认识印度与欧亚大陆碰撞造山过程中的成矿作用特点具有重要意义。

GEOLOGICAL CHARACERISTICS AND GENESIS OF XUESHAN TUNGSTEN MOLYBDENUM BISMOTH AND COPPER POLYMETALLIC DEPOSIT IN JIAGANG ON THE NORTH MARGIN OF GONDISE MASSIF, TIBET

North margin of Gandise massif is one of the important polymetallic ore forming belt in Tibet. Jiagang tungsten Molybdenum bismuth and copper polymetallic deposit found in north part of the massif for the first time is a new genetic type of deposit which is different from the porphyry type copper polymetallic deposit in the south. The discovery of the deposit is a great breakthrough in endogenesis metallic ores prospecting in north Tibet. Until now there have been more than ten large scale, high grade and easy to mine and separate wolfromite -molybdenite-quartz veins found in the ore field. The vein bodies occur in the inner and outer contact of muscovite adamellite with the inner contact as a main ore belt. It is shown that the mineralization is closely associated with intermediate to acidic magma activities under the collision of earlier Himalayan orogeny and is a typical magmatic gas and liquid-filling type wolfromite-quartz lode type deposit. The discovery of the deposit is of great significance to further understand the metallogenic characteristics during collision orogenic movement of Indian plate with Euro-Asia continent