西藏主要金矿成矿带成矿地质构造条件剖析

西藏主要金矿成矿带与板块缝合带或开裂－闭合带相对应，矿带的形成与特提斯海的形成、演化密切相关。矿带内矿床的形成是矿源、水源、热源相互作用的结果。不同成因的含矿热液由封闭体系进入开放体系时（物理体系发生突变），热液沸腾、围岩蚀变、矿质卸载并赋存于受特定地层层位控制的韧性剪切带内。“黑色”岩系地层不仅是岩金成矿的重要矿源层，同时也是砂金成矿的主要物源。“红”“黑”岩系并存是砂金成矿的有利区段（水化学体系发生突变），也是寻找砂金矿的找矿标志之一。岩金（包括矿源层、矿体等）的贫化是砂金成矿的主因，二者互为消长关系。

GEOLOGICAL AND STRUCTURAL ANALYSIS ABOUT THE GOLD METALLOGENIC ZONE IN XIZANG (TIBET)

The gold deposits in Xizang (Tibet) occur generally in the structurally altered rocks of the terigenous "black" rock series in the plate suture zones characterized by bidirectional subduction or in the open shut zones of the intraplate back arc basins. The ocurring modes of the gold deposits have revealed that the activization and mineralization of gold are closely bound up with the tectonic-hydrothermal activity. The "black" rock series are believed to be the primary provenace of organic matter and gold ,and aqueous solution is considered as the media and carrier of ore solution. Tectonism may supply the energy for the activization and migration of gold.