青海抗得弄舍金多金属矿床矿化蚀变与富集规律研究

Mineralization alteration and enrichment regularity of Kangdenongshe gold polymetallic deposit in Qinghai

文章系统地研究了矿床蚀变矿物组合、近矿围岩蚀变及金矿化特点,表明矿化与蚀变具有明显的空间分带特征。从赋矿层位看,铅锌矿化产于流纹质凝灰岩中,反映了火山沉积作用对铅锌成矿的控制;而金矿化产于灰岩与流纹质凝灰岩的接触面上及其附近。空间上金矿体分布在矿体前锋,铅锌矿体分布在矿体中部、尾部和矿体上盘围岩中,具有金矿体在上部,铅锌矿体在下部的分带特征。与成矿作用关系密切的围岩蚀变是重晶石化,其次为硅化和绢云母化等,垂向自上而下绿帘石化、黄铁矿化普遍发育,在矿体中深部位重晶石化、硅化普遍发育,与金成矿关系密切。

The altered mineral association, wallrock alteration and gold mineralization feature were systematically studied, the result showed that there is obvious spatial zonation of the mineralization and alteration. In view of ore-hosting strata, the lead-zinc min- eralization mainly occurs in the rhyolitic tuff, which indicated that the lead-zinc mineralization was controlled by volcanic sedimental process, and gold mineralization mainly occurs in the interlayer between the limestone and rhyolitic tuff or the nearby.In space, the gold ore bodies distributed in the forward part, and the lead-zinc orehody in the central and back part and in the hanging wall rock. In the vertical direction, the gold orebody in the upper part, but the lead-zinc orebody in the lower part. The wallrock alteration closely related to mineralization is baratization, secondly is silicification and sericitization. In the vertical direction, epidotization and pyritization become intensively from the top to the bottom, but baratization and silicification are intensive in the central part which are closely related to gold mineralization.