甘肃寨上大型金矿床南、北矿带地质地球化学特征对比研究

摘要

Zhaishang gold deposit can be divided into south and north ore-belt with the F5 fault as boundary,and geological and geochemical difference exists between them .The north ore-belt occurs in lower Permian Shilidun group at north limb of the anticline and the south ore belt is located in the mid-Devonian Anjiacha group and upper-Devonian Dacaotan group in the core of the anticline .The inclusions study shows that the ore-forming hydrothermal fluid is char-acterized with min-low temperature,low salinity,density and pressure which suggest ores formed in the shallow .How-ever,compared with the north ore-belt,the ore forms from fluids with higher temperature,salinity,density,pressure and in deeper position in the south ore-belt.The south and north ore-belt belong to a unified hydrothermal system ,which presents micro-fine disseminated gold mineralization in the shallow as the case in north ore belt and rich-gold poly-metallic vein type mineralization in the deeper part as in south ore belt .%　　寨上金矿床以F5断裂为界，可分为南、北2个矿带，在地质、地球化学特征方面存在差异。北矿带位于背斜北翼下二叠统十里墩组地层中，南矿带产于背斜核部中泥盆统安家岔组、上泥盆统大草滩组地层中。流体包裹体研究显示，矿床总体具有中低温、低盐度、低密度、低压力和较浅的成矿深度，南矿带相对于北矿带成矿温度、流体盐度、密度要高，成矿压力以及成矿深度要大。南北矿带可能为一个统一的热液成矿系统，浅部表现为类似于北矿带的微细浸染型金矿化，深部表现为类似于南矿带的脉状富金多金属矿化。