Mineralization mechanism ore formation mechanism
Under certain geological structural conditions, the physical and chemical effects of enrichment of chemical element and mineralization and the relationship between the controlling factors and the mutual constraints of mineralization.
The goal of mineralization geochemistry and mineralization mechanism research is to find out the chemical or physical effects that lead to element enrichment, ascertain the many controlling factors and the mutual constraints between them, and further apply geochemistry Theoretical analysis and calculation of thermodynamics and kinetics, and construction of geochemical models and kinetic models showing the formation process of mineral deposits and their control relationships. The research on the mineralization mechanism of
is particularly helpful to understand the conditions for the formation of large ore and rich ore and to guide the exploration and prediction work. The enrichment of
elements under natural conditions and the formation of mineral deposits is a complex dynamic process that occurs spontaneously and must occur under favorable and appropriate geological structures and geochemical environments.
These favorable conditions include: sufficient mineral and fluid sources, continuous regional tectonic or thermodynamic driving effects, a set of chemical reactions or physical and biological effects that enrich elements, and geology that ensures the continued progress of the mineralization reaction system. Tectonic and physical and chemical environment, etc.
Among them, the chemical, physical and biological effects that lead to the high concentration of elements are of particular importance for the formation of rich ores and large ores.
For example, hydrothermal sulfide deposits produced in tensile-shear structural fissures usually cause hydrothermal fluids to invade and fill along the structural fissures during the rupture and expansion process of the tensional fractures, and at the same time heat The liquid system boils, and the fluid phase in the hydrothermal liquid, water, carbon dioxide, and hydrogen sulfide, escapes, destroying the balance of the hydrothermal system, and the carried metal elements react with sulfur to form sulfide minerals that precipitate and enrich.
For the occurrence of this mineralization and enrichment mechanism, there must be favorable regional tectonic activities, sufficient cyclic supply of ore-bearing hydrothermal fluid sources, and favorable surrounding rock alteration reactions as balanced buffer reactions to maintain the mineralization chemistry. Only when the reaction continues can large and rich mineral deposits be formed.
Excerpted from: "Encyclopedia of China (2nd Edition)" Volume 3, Encyclopedia of China Press, 2009
