What is the cause of dolomite?
Closely related dolomitization and deep basin, generally by deep hydrothermal dolomitization in control; the development of basin, the deep crust exists a low velocity high conductive layer in the crust. In the deep of the low velocity high conductive layer is serpentinized peridotite, release a large number of Mg2+ in the serpentinization process, Mg2+ bearing hydrothermal rise to strong mg replacement and CaCO3 basin in carbonate rocks, the formation of dolomite.
Dolomite exists in crystalline limestone and other rocks rich in magnesium in part produced in hydrothermal veins and carbonate rock pores, occasionally as cements of different sedimentary rocks, is one of the most common rock forming minerals in carbonate rocks.
Dolomite crystals belong to the three system of carbonate minerals 1. The chemical composition is CaMgCO32. Magnesium substituted for dolomite, manganese, etc.. When the number of iron or manganese exceeds that of magnesium, it is called dolomite or manganese dolomite. Three crystal system, crystal is rhombohedral, crystal surface is often bent into saddle shape, poly double crystal is common. Aggregates are usually grainy. Pure is white; gray when iron; brown after weathering. Glassy luster. Slowly foaming when cold hydrochloric acid is diluted. It is the main mineral of dolomite. Marine sedimentary dolomite is often interbedded with siderite and limestone. In lacustrine sediments, dolomite and gypsum, anhydrite, halite, sylvite, symbiosis.
