甘肃省迭部县加勒克金矿地质特征及成因探讨

Geological characteristics of Jialeke gold deposit in Diebu county,Gansu and its genesis

加勒克金矿呈脉状、不规则囊状或漏斗状产于西秦岭造山带古道岭组灰岩中,矿化受到NWW向和近EW向断裂严格控制,矿石矿物以赤铁矿、自然金和黄铁矿为主,蚀变以硅化、绢云母化和褐(赤)铁矿化为特征。矿石主要为碎裂岩型、硅化碎裂斑岩型、碎裂灰岩型。成矿作用方式主要为热液渗滤交代、构造裂隙等有限空间的充填沉淀作用,构成比较完整的热液交代-充填-沉淀成矿体系经历了原生热液成矿期和表生氧化-次生富集期。成矿环境为近地表,成矿时代为印支晚期,成矿物质来源与印支期陆内造山阶段酸性岩浆活动密切有关,金矿化和岩浆岩可能是统一的受深部构造制约的印支期构造-岩浆-热液活动体系的系列演化产物。

Jialeke gold deposit occurs in Gudaoling Group（D2g） limestone in west Qinling orogenic belt in the form of irregular pocket or funnel,with the mineralization being strictly controlled by EW striking fracture and ore minerals predominated by hematite,natural gold and pyrite,and alteration characterized by silicification,sericitication and limonite（hematite）mineralization.Ore forming processes can be classified into primary ore forming period and surface oxidation-secondary enrichment period.Ore types are mainly limonite mineralization,argillation,clastic rock type,pyritization（limonite）,silicification,carbonation clastic limestone type.Ore fabric and mineral assemblage indicate that the ores were mainly formed by hydrothermal filtration replacement and filling sedimentation in limited space in fissures or structures,forming relatively completed hydrothermal replacement-filling-deposition metallogic system.The environment for ore forming is near surface and metallogenic era is late Indo-Chinese epoch,ore matter origin is closely associated with acidic magma activities in inner continent orogenic stage in Indo-Chinese epoch,gold mineralization and magmatic rocks are presumed to be the evolution product of an integrated Indo-Chinese epoch structure-magma-hydrothermal system dominated by deep rooted structure.