秦岭成矿带金成矿规律及资源潜力OA

The Qinling metallogenic belt is one of China's most important Au-polymetallic metallogenic belts and the country's second-largest Au-metallogenic belt after Jiaodong.In recent years,new breakthroughs have been achieved in many deposits such as Zaozigou,creating an urgent need for in-depth research on its Au-metal-logenic regularities and resource potential.Based on a systematic review of strata,structures,magmatism,geo-physical-geochemical characteristics,and the metallogenic setting,mineralization features,and ore-controlling factors of 613 Au deposits(or occurrences)within the belt,this study reveals that Au deposits in the Qinling metallogenic belt display a spatial pattern of"NW-trending belts and NE-trending clusters".Large Au deposits commonly occur at the intersections of NW-and NE-trending structures and in areas with intense magmatic ac-tivity.The Au metallogenesis of the eastern and western Qinling exhibits significant differences.In western Qin-ling,most Au deposits are hosted in the Devonian,Permian,and Triassic strata,with mineralization ages concen-trated at 250～230 Ma and 225～210 Ma,closely related to contemporaneous magmatism.Metallogenic types include hydrothermal type hosted in metamorphosed clastic rocks and magmatic-hydrothermal type.In eastern Qinling,Au deposits are mainly hosted in the Archean Taihua Group,the Cambrian,and the Devonian strata,with mineralization ages primarily between 145 and 110 Ma.Their metallogenic type is mainly magmatic-hy-drothermal type.For crustal structure,western Qinling shows crustal decoupling influenced by the expansion of the Tibetan Plateau,with deep magmatic channels controlling the distribution of Au deposit districts.In contrast,eastern Qinling exhibits high-conductivity crust-mantle penetrating structures influenced by the Paleo-Pacific Plate,contributing to the Yanshanian metallogenesis.Through comprehensive comparison,this study delineates 25 fourth-order Au metallogenic sub-belts and 10 Au metallogenic series within the Qinling metallogenic belt.Among these,the two most important series are the Indosinian series related to intermediate-felsic magmatic in-trusions and the Yanshanian series associated with magmatic-hydrothermal activity.Integrating geological,geo-physical,and geochemical information,73 prospective Au exploration targets are identified within the Qinling metallogenic belt(28 Class I,34 Class II,and 11 Class III).Based on the metallogenic regularities and resource-potential assessment,It is suggested that exploration in western Qinling should focus on the Xiahe-Hezuo and Zhaishang-Liba ore districts,targeting the deep and peripheral zones of existing deposits.In addition,explo-ration should also be strengthened in Huayagou-Jiutiaogou,FengTai,and other prospective areas,and particular attention should be given to concealed orebodies related to magmatic-hydrothermal activity in the Wenxian-Kangxian ore district.In eastern Qinling,the application of integrated geophysical techniques should be en-hanced for deep-level exploration.Deep exploration should be prioritized in the Xiaoqinling ore district,with special attention to deep and peripheral zones of known deposits such as Xiajiadian,Liujiaxia,and Sulinggou.