Abstract:
Since the implementation of the Exploration Breakthrough Strategic Action organized by the former Ministry of Land and Resources in 2011, great achievements have been made in the deep prospecting of Jiaodong gold deposit, with the newly increased gold resources of about 2958 t.12 large gold deposits have been explored and evaluated, and 2 super-giant gold deposits have been found.The accumulated proven gold resources in Jiaodong Peninsula have reached more than 5000 tons, accounting for 1/3 of the whole country.These prospecting achievements are attributed to the deepening understanding of metallogenic theories such as metallogenic tectonic setting, metallogenic regularity and genesis of deposits and the continuous progress of exploration techniques and methods.The metallogenesis and related research of the Jiaodong gold deposit are the hotspots of domestic geological research.This article briefly summarizes the research progress in the recent 10 years in metallogenic background, deposit distribution, metallogenic epoch, geochemistry of ore deposit, metallogenic model and genesis, especially the original achievements in the research of deep metallogenic model and large-scale metallogenic mechanism.These results indicate that the Jiaodong gold deposit was formed in the magmatic activity background of adakite granite transformed into arc granite, the geochemical transformation of magmatic rocks and lithospheric mantle provides material sources for gold mineralization, the Early Cretaceous thermal doming-extension structures provided favorable conditions for large-scale gold mineralization, the change of fault dip angle controlled the fluid accumulation and the ore-rich pillars, the source of ore-forming materials and fluids have mantle-derived factors, and the Jiaodong type gold deposit is a new genetic type of gold deposit, which is different from the classical orogenic gold deposit and other known types.The exploration of the Jiaodong gold deposits comprehensively applied prospecting methods such as deep geophysical exploration, structural superimposed halo geochemical prospecting, three-dimensional geological modeling and deep drilling, etc., The ladder prospecting method for deep gold deposits, which takes the location of ore bearing structure as the target and frequency domain electromagnetic detection as the main technical means, plays an important role.This paper summarizes the important progress of deep exploration.The deep gold resources are concentrated in the depth of -1000 m to -2000 m, most of which are fracture zone altered rock type mineralization.Several shallow ore bodies in Sanshandao area and Jiaojia area are connected to the deep, forming a super-giant gold deposit with resources greater than 1000t.In recent years, the first offshore gold deposit in China has been discovered, and the pyrite carbonate vein type gold deposit has been defined as a new type in the east of Jiaodong.Finally, this paper briefly analyzes the unresolved problems in the deep exploration research of the Jiaodong gold deposit, and points out that the influence of Late Mesozoic structural system transformation on large-scale mineralization, the mechanism of fault-controlling ore, the source of ore-forming fluids and materials, the potential of gold resources and the fine and efficient prospecting techniques are the key research direction in the future.