The Thermal and Dynamic Process of Core → Mantle → Crust and the Metallogenesis of Guojiadian Mantle Branch in Northwestern Jiaodong

摘要

The Jiaodong gold mineral province, with an overall endowment estimated as 3000 t, located at the eastern segment of the North China Craton (NCC), ranks as the greatest source of Au in China. The structural evolution, magmatic activity and metallogenesis during the Mesozoic played important roles in the large scale regional gold, silver and polymetallic mineralization in this area; among them, the intensive activation of fault structures is the most important factor for metallogenesis. This study takes the regional deep faults as main thread to discuss the controlling role of faults in large scale metallogenesis. The Jiaojia fault and Sanshandao faults in the northwest margin of the Guojiadian mantle branch not only are dominant migration channels for hydrothermal fluid but are very important favorable spaces for ore-forming and ore-hosting during the formation of world-class super large gold deposits in this area. The deep metallogenic process can be summarized as involving intensive Earth’s core, mantle and crust activity → magmatism → uplifting of metamorphic complex → detachment of cover rocks → formation of mantle branch → penetration of hydrothermal fluid along deep faults → concentration of metallogenic materials → formation of super large deposits.