Lithogeochemistry of altered rocks and mineralization in Xindongzhuang Gold Deposit,northwest Jiaodong peninsula
Xindongzhuang Gold Deposit is located in the middle section of the Zhaoping fault zone,and its ore bodies are mainly distributed along the contact zone between the Mesozoic Linglong granite and Archean Jiaodong Group metamorphic rocks.Beresite is the main mineralized rock.The Linglong granite at the footwall of ore bodies is mainly characterized by red alteration,while the metamorphic rocks in the Jiaodong Group at the hanging wall are marked by propylitization.The main elements analysis reveals the increased contents of K2O,SiO2,SO3,and LOI,which are carried components,in the granite with red alteration,beresite,and sericitolite relative to Linglong granite,in particular for the beresite,and sericitolite that are closely related to mineralization.Among microelements,Rb and U are also commonly carried in the granite with red alteration,beresite,and sericitolite.Gold mineralization at Xindong-zhuang Gold Deposit is closely related to changes in oxygen fugacity and acid and alkali conditions,and the enrichment of gold mainly occurs under reductive and slightly acidic conditions.