内蒙古乌奴格吐山次火山斑岩型铜-钼矿床控矿因素分析及找矿方向

Ore controlling factors of subvolcanic porphyry type coppermolybdenum deposit in Wunugetushan of Inner Mongolia,and its ore prospecting orientation

乌奴格吐山铜-钼矿床属于受火山机构控制的陆相次火山斑岩型铜-钼矿床。矿体主要赋存在以次斜长花岗斑岩岩体为中心的环状分布的内外接触蚀变带中。研究认为,与火山机构有关的特别是次火山活动最强烈时期形成的多期次浅成—超浅成相中酸性次火山侵入体与铜-钼矿床的形成关系密切,石英-钾长石化及石英-绢云母化等交代型分带明显的面状蚀变晕等均是区域内斑岩型铜-钼矿床主要找矿标志。

The Wunugetushan copper-molybdenum deposit belongs to continental subvolcanic porphyry copper-molybdenum deposit controlled by volcanic mechanism. The major fracture system consists of northeast trending and northwest trending fractures in the joining part of whom, the volcanic mechanism occurs and the ore carrying magmatic rock-sub-plagiogranite porphyry is controlled by volcanic mechanism occurring in volcanic pipe （partly intersecting volcanic pipe）, being the central location of volcanic magma activities. In the meantime some ring-shaped and radiated fractures formed in the volcanic mechanism with thin or thick wall of the volcanic pipe, all providing favorable structure space for the penetration of ore bearing hot fluid and extensive replacement, resulted in the forming of facial alteration- mineralization zone. The orebodies mainly occur on the ring shaped inside and outside contact alteration zones centered at sub-plagiogranite porphyry. The multi-period supergene phase intermediate to acid subvolcanic intrusive rocks formed especially through the most serious subvolcanic activities, associated with volcanic mechanism at the volcanic-structure and magma activity center. F face-shaped alteration haloes with clear zonings of quartz-feldspar and quartz- sericite type replacement are all the main targets for the prospecting of porphyry type copper-molybdenum deposit.