闽西南双宁坑石英岩矿床控矿要素与成矿预测研究OA

The Shuangningkeng quartzite deposit in Yong'an City,Fujian Province,is a typical sedimentary-metamorphic quartzite deposit in southwestern Fujian.Based on field geological investigation and comprehensive laboratory analysis,this paper systematically analyzes the geological characteristics of the deposit,with emphasis on determining the contributions and coupling relationships of four types of ore-control factors:stratigraphy,regional metamorphism,structure and magmatism.The results indicate that the high-maturity coarse clastic rocks of the upper member of the Upper Devonian Taozikeng Formation constitute the material foundation for mineralization;regional epimetamorphism facilitated the solid-state recrystallization and quality enhancement of quartz grains;the synclinal structure in the mining area is the key factor controlling the morphology and spatial distribution of orebodies,and quantitative analysis using balanced cross-section technique shows an average shortening rate of 7.1％,indicating a gentle fold type;late-stage granite porphyry dikes partially disrupted the continuity of orebodies.On this basis,a multi-factor combined ore-control model of"sedimentation foundation-metamorphic transformation-structural shaping-magmatic destruction"is proposed.Accordingly,the deep synclinal core and the NNW plunging end of the mining area are delineated as the Class Ⅰ prospecting target,while the Upper Devonian-Lower Carboniferous strata distribution areas in southwestern Fujian are designated as the Class Ⅱ prospecting target.The results of this study can provide a reference for further exploration of this deposit and for regional prospecting of similar deposits.