西藏驱龙超大型斑岩铜(钼)矿床:发现、特征及意义

Finding, Characteristics and Significances of Qulong Superlarge Porphyry Copper (Molybdenum) Deposit, Tibet

驱龙斑岩铜 (钼 )矿床位于冈底斯东段火山岩浆弧与日多盆地的弧 -盆转换部位 ,受盆缘控盆、控岩构造控制 ,形成于汇聚造山向伸展走滑转换的瞬时过渡环境 (15～ 16Ma) ,是冈底斯东段新发现的最具找矿潜力的超大型斑岩铜 (钼 )矿床 ,也是该带斑岩矿床勘查的重大突破 .该矿床成矿流体为饱和及过饱和盐水 -蒸气沸腾流体 ,蚀变具有以斑岩体为中心、面状、环带分布特征 ,矿化分为 3期 5阶段 ,硬石膏化及绢英岩化与铜矿化关系密切 .并对一些今后必须加强研究的关键性科学问题进行了探讨 .

Qulong porphyry copper(molybdenum) deposit, which is located in the arc-basin transform place between the magma arc of eastern Gangdise and Riduo basin, controlled by basin-controlled, rock-controlled structure in basin edge, and formed in instantaneous transition environment of transform from convergent to extension, is the most potential superlarge deposit in ore-finding and its finding is the important breakthrough in the exploration process of porphyry deposit in eastern belt of Gangdise Mountain. The ore fluid of Qulong porphyry copper(molybdenum) deposit is composed of saturation and supersaturation brine-steam boiling fluids; its distribution characteristics of wall rock alteration include centering by porphyry, surfacing, and annular zone; it has undergone mineralization of 3 periods including 5 phases. It is found that the copper mineralization correlates with anhydrition and sericitization. This paper also probes into some key science issues which call for further studies and attention.