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白云石作为一个重要的造岩矿物,其成因至今仍未确定。主要的原因是由于白云石在低温条件下难以沉淀。然而,通过对溶液中诸如硫酸根离子和镁的浓度的变化在较易沉淀的类白云石矿物BaMg(CO_3)_2和PbMg(CO_3)_2沉淀过程中的影响进行研究,可使我们深入了解白云石自身沉淀的环境。在25—80℃的温度范围内,PbMg(CO_3)_2在含硫酸盐的溶液和不含硫酸盐的碱性溶液中沉淀的难易程度是相同的。类白云石矿物可在这些溶液中沉淀表明,白云石亦可在类似的溶液中沉淀而不必考虑溶解硫酸盐(SO_4~(2-))的浓度。在有BaCO_3子晶的含硫酸盐溶液中只沉淀重晶石而不沉淀钡白云石。其原因可能是由于重晶石的热力学溶解度相对较低,而不是存在溶解的硫酸盐抑制了钡白云石的沉淀。
Dolomite as an important rock-forming mineral, its cause has not been determined. The main reason is because dolomite is difficult to precipitate at low temperatures. However, a study of the effect of changes in concentrations of solutions such as sulfate ions and magnesium on precipitation of the more dolomite-like dolomites BaMg (CO_3) _2 and PbMg (CO_3) _2 precipitated allows us to gain insight into the effects of Baiyun Stone itself precipitated environment. The ease of precipitation of PbMg (CO 3) 2 in sulphate-containing and sulphate-free alkaline solutions is the same for the temperature range 25-80 ° C. The precipitation of dolomite-like minerals in these solutions suggests that dolomite can also be precipitated in similar solutions without regard to the concentration of dissolved sulphate (SO 4 2-). In the sulfate solution containing BaCO_3 subgrains, only barite is precipitated without precipitation of barium dolomite. The reason may be due to the relatively lower thermodynamic solubility of barite, rather than the presence of dissolved sulphate, which inhibits the precipitation of barium dolomite.