滇黔桂地区微细粒浸染型金矿床的矿床地球化学类型

GEOCHEMICAL TYPES OF THE WCRO- AND FINE-GRAINED DISSEMINATED GOLD DEPOSITS INYUNNAN-GUIZHOU-GUANGXI REGION

根据矿床产出的区域构造背景、含矿建造的岩性特点和沉积环境、矿石的矿物共生组合和成矿元素组合以及标型矿物的成分特征等，将滇黔桂地区的微细粒浸染型金矿床划分为三种矿床地球化学类型：金－锑－黄铁矿型矿床、金－汞－（铊）型矿床和金－砷－（锑）型矿床；并分别做了描述。

n the basis of such factors as the regional tectonic setting of the oredeposits, the lithology and sedimentary environment of the ore-bearing fco-matzons, the mineral assemblages and metallogenic element associations of theores, the compositional characteristics of the typomorphic minerals, the ti`tho-loocric, pehoochemical, trace element and rare earth element characteristiee ofthe mineralized host reeks, the coniposition, degree of mineralization andphyslcalchemical properties of the fhiid inclusions, and the stable isotopecomposition of sulfur, hydzogen and oxygen, the micro- and fine-grained disse-minated gold depeeits might be geochemically classified into three types,namely gold-antimony-pyrite type, gold-mercury-(thallium) type and gold-arsenic-(antimony) type.The differences of geological-geochemical characteristics between thesethtee geMiemical types of gold deposits reflect their different source bedswhicli were formed in different geological settings and sedimentary environ-ments. The source bed of the gold-antimtony-pyrite type gold deposits is thevolcanogene sedimentary formation produced in the littoral tidal facies at theinitial rift-faulting stage of the rift evolution; the source bed of the gold-mercury(thallium) type depcoits is the carbonate-claystone formation formedin the restictedsemirestricted platiorm neritic facies at the initial spreadingsubsidence stage of the rift evolution; the soutce bed of the gold-arsenic--(antimony) type gold depcoits is the tiirbidite formation developed along themarginal slope facies of the open-sea basin at the intense subsidence stage ofthe rift evolution.