藏东玉龙斑岩型铜(-钼-金)矿床地质特征及找矿标志

Geological characteristics and prospecting indicators of Yulong porphyry Cu(Mo-Au)deposit in eastern Tibet

玉龙斑岩铜(-钼-金)矿床处于特提斯喜马拉雅构造域东部的三江特提斯造山带的北缘,受区域上恒星错-甘龙拉背斜和喜山期岩浆侵位的双重控制。本文通过对玉龙斑岩铜(-钼-金)矿床详细野外地质调查,发现斑岩型铜(-钼-金)矿体主要赋存于浅成-超浅成的二长花岗斑岩复式岩体中,空间上呈蘑菇状,平面上呈梨状。矿石构造主要以网脉状构造和细脉浸染状构造为主。玉龙斑岩铜(-钼-金)矿床围岩蚀变分带明显,由岩体中心向外依次为:钾化带→钾硅化带→绢英岩化带→硅化黏土化带→强黏土化带。矿体主要产于绢英岩化带和硅化黏土化带中。文章在详细的研究矿床地质特征、地球化学特征基础上,总结了岩性标志、基底标志、褶皱标志、颜色异常标志、蚀变及蚀变带标志、铁帽标志以及地球化学标志,为寻找同类型的斑岩铜(-钼-金)矿床提供重要的参考依据。

The Yulong porphyry Cu(Mo-Au)deposit is located in the northern margin of the Sanjiang Tethys orogenic belt in the eastern part of the Tethys Himalayas,and is regionally controlled by the Hengxingcuo-Ganlongla anticline and the Himalayan magmatism.Based on the detailed field geological survey of the deposit,it is found that the porphyry Cu(Mo-Au)ore body mainly occurs in the hypabyssal-super hypabyssal monzonitic granite porphyry complex.The ore body is mushroom-shaped in space and pear-shaped in plane.The ore structure is dominated by veined-network and veinlet-disseminated structure.The wall rock alteration of the deposit is obvious.From the center to the outside of the complex,it is potassium,potassium-silicification,sericitization,silicified clayization,and strong clayization zones.And the ore body mainly occurs in the sericitization and silicified clayization zones.Based on the detailed study of the geological and geochemical characteristics of the deposit,this paper preliminarily infers the lithology,basement,fold,color anomaly,alteration and alteration zone,gossan,and geochemical marks,which can be used as an important reference for searching for the same type of porphyry Cu(Mo-Au)deposits.