Sun Zhongshi

Crust-mantle structures and gold enrichment mechanism of mantle fluid system

Gold enrichment mechanism of ore-forming fluid is the essence of gold metallization. This paper summarizes the distinguishing symbols of mantle fluid and effect of crust-mantle structure on fluid movement. Fluid moving processes include osmosis, surge, gas-liquid alternation and mutation of fluid speed. During fluid movement, gold will be enriched gradually. Finally, a layered circulatory system is illustrated in this paper.

Origin of Gold-Bearing Fluid and Its Initiative Localization Mechanism in Xiadian Gold Deposit, Shandong Province

The composition of quartz inclusions and trace elements in ore indicate that gold bearing fluid in the Xiadian gold deposit, Shandong Province, stemmed from both mantle and magma, belonging to a composite origin. Based on theoretical analysis and high temperature and high pressure experimental studies, gold-bearing fluid initiative localization mechanism and the forming environment of ore-host rocks are discussed in the present paper. The composite fluid extracted gold from rocks because of its expanding and injecting forces and flew through ore-conducive structures, leading to the breakup of rocks. The generation of ore-host faults and the precipitation of gold-bearing fluid occurred almost simultaneously. This study provides further information about the relationships between gold ore veins and basic-ultrabasic vein rocks and intermediate vein rocks, the spatial distribution of gold ore veins and the rules governing the migration of ore fluids.