Skarn deposits

摘要: Skarn consists of coarse-grained Ca-Fe-Mg-Mn silicates formed by replacement of carbonate-bearing rocks accompanying regional or contact metamorphism and metasomatism. The major processes which result in skarn include metamorphic recrystallization of impure carbonate rocks, bimetasomatic reaction between unlike lithologies, and infiltrational metasomatism involving hydrothermal fluids of magmatic origin. Metal deposits that contain skarn as gangue, termed skarn deposits, may be formed by any combination of the above processes. However, the majority of the world’s major skarn deposits are thought to be related to magmatic-hydro-thermal systems; these are the skarn deposits treated in this paper. Skarn deposits are among the most abundant and variable of all types of mineral deposits; yet, in spite of their diversity, they exhibit systematic geologic, petrologic, and mineralogic features which permit …