Discussion on Metallogenic Regularity and Metallogenic Model of Lidonggou Gold Deposit in Hanzhong,Shaanxi Province
The Lidonggou gold deposit represents the first newly identified endogenous gold deposit in recent years within the basement cap rock of the Beiba area in Hanzhong area,Shaanxi Province.Over 20 gold ore bodies have been delineated,with lengths ranging from 70 to 1 400 meters,and an average thickness between 0.31 and 9.8 meters.The gold grade varies from 0.83×10-6 to 21.21×10-6,classifying it as a medium-sized deposit.The gold deposit is predominantly hosted within the marble and sericite quartz schist of the Mawozi Formation,and is controlled by north-northeast trending fault structures.The ore types predominantly consist of breccia and quartz vein,formations,characteristic of a tectonically altered rock and quartz vein-type gold deposit.The principal metallic minerals identified include native gold,pyrite,molybdenite,and chalcopyrite.Mineralization processes are primarily characterized by limonitization,pyrite mineralization,and magnetite mineralization,with sporadic occurrences of malachite and azurite mineralization.Silicification,tourmalinization,and gold mineralization exhibit a close interrelationship.Preliminary analyses suggest that the formation of the Lidonggou gold deposit has undergone four distinct stages:The formation of ore layers encompasses several processes,including early-stage gold formation,ore enrichment and mineralization,as well as supergene weathering and erosion.The mineralization process is categorized into three distinct stages:The post-magmatic hydrothermal mineralization phase occurring during the Jinning epoch,the post-magmatic hydrothermal superimposed transformation mineralization phase during the Chengjiang epoch,and the supergene oxidation phase.The"stage of quartz,native gold,and polymetallic sulfides"constitutes the principal mineralization phase in this region.The mineral assemblage during this stage includes quartz,native gold,pyrite,molybdenite,chalcopyrite,and sphalerite,which collectively signify the primary phase of gold re-enrichment in the area.Drilling verification reveals that the orebody trends southwestward at greater depths.While the deep extension of quartz vein-type gold orebodies within quartz sericite schist is constrained,the deep extension of interlayer fractured zones in marble exhibits relative stability,with a large number and significant scale of controlled gold orebodies,presenting good prospecting potential.The proposed strategy emphasizes the deployment of shallow work control,particularly targeting quartz vein-type gold ore bodies within quartz sericite schist.Additionally,the focus will be on the exploration and assessment of breccia-type and quartz vein-type gold ore bodies influenced by marble interlayer fracture zones in the mid-depth regions.The primary exploration objectives and directions include the implementation of medium-depth engineering verification,boundary expansion exploration,and the identification of concealed orebodies.This understanding can serve as a foundational basis for the exploration and expansion of the mining area,while also offering critical guidance for the identification of similar gold deposits within the region.
metallogenic regularitymetallogenic modelLidonggou gold mineHanzhong areaShaanxi Province
万方数据
维普
