胶东地区首次发现厚大斑岩型铜钼矿:华北克拉通东部周缘实现斑岩型矿床找矿突破OA

Porphyry copper deposits represent the most important type of copper resources,a strategic and scarce metal.Significant breakthroughs have been achieved in the Tethys and Central Asian Metallogenic Domains,yet little progress has been made for a long time in the periphery of the eastern North China Craton within the Circum-Pacific Metallogenic Belt.This study reports the first discovery of thick porphyry copper-molybdenum polymetallic orebodies in the Xiangkuang area,located on the southern margin of the Zangjiazhuang Basin within the northeastern Jiaolai Basin.This discovery represents a major breakthrough in the type of copper-molybdenum deposits in the region.Through systematic geological surveys,drilling validation,and comprehensive research,we detail the geological characteristics,metallogenic architecture,and exploration techniques of this deposit,and discuss its regional metallogenic potential and future prospecting directions.The results indicate that:(1)Seven completed drill holes reveal a"two-story"metallogenic architecture,with skarn-type orebodies in the upper section and porphyry-type orebodies as the main body in the lower section.A single hole intersected a maximum cumulative ore thickness of 191.92 m,containing associated and by-product components like molybdenum,silver,sulfur,cadmium,and gallium,indicating significant potential for comprehensive utilization.(2)Mineralization is closely related to Late Yanshanian granodiorite porphyry,exhibiting distinct vertical zonation from shallow to deep:"lead-zinc mineralization→copper mineralization→copper-molybdenum mineralization→molybdenum mineralization".(3)Based on the vertical electrical property differences of the metallogenic geological bodies,a three-layer electrical structure model characterized by"high resistivity at the top and bottom,low resistivity in the middle"has been established.This led to the development of an effective exploration technique combination centered on the Controlled Source Audio-frequency Magnetotellurics method.(4)The ore-forming materials exhibit a crust-mantle mixed source,the concealed intrusion is large in scale with substantial resource endowment per unit area,indicating significant prospecting potential at depth and on the periphery.This study suggests that the periphery of the eastern North China Craton holds the potential to host giant porphyry copper deposits and ore concentration areas.We propose two levels for future prospecting deployment:"the depth and periphery of known mining areas"and"the regional metallogenic belt".This achievement not only reshapes the copper exploration landscape in the eastern North China Craton but also provides an important theoretical basis and technical demonstration for exploring similar deposits within the region.