Abstract The study included five locations in Kurdistan Region, Iraq, represented by the soils of Zawita, Zakho, Dukan, Smaquli and Aqrah, order to know solubility precipitation carbonate minerals based on values omega (Ω) saturation index (SI) using water different ionic strength (chloride water, sulfur Tigris river water).the results showed that dolomite mineral was more precipitated term (9....