The influence of crystal size of dolomite on engineering properties: a case study from the Rus Formation, Dammam Dome, Eastern Saudi Arabia

The goal of this study is to comprehend the connection between petrographic features especially the grain size of dolomitic rocks and engineering properties. Three types of dolomite were selected for this study: fine, medium and coarse, all from the same formation with the same mineral content but varying grain sizes. Samples of dolomite from the Rus Formation, Damman Dome, eastern Saudi Arabia province, were studied. The dolomite samples were mineralogically similar but varied in crystal grain size from fine-grained, medium-grained, to coarse-grained types. The experimental tests included the point load strength index, uniaxial compressive strength, P wave, dry and saturation densities of samples. The results suggest that textural factors have a greater influence on the engineering properties of dolomite than mineralogical composition. It was also revealed that the crystal size (fine to coarse) is a textural element and that it has a significant impact on the mechanical and physical properties of the dolomite under investigation. In addition, multivariate linear regression was employed in four separate stages for each engineering parameter, using different combinations of petrographical properties. Density and point load strength, uniaxial compressive strength, tensile strength and Böhme abrasion rise with increasing crystal size. Finally, the optimum equations with special arrangements for estimating engineering properties of Rus Formation dolomite were proffered. The correlation between these values allowed more than 95% accuracy in generating equations for predicting mechanical performance from the mineralogical composition of Rus Formation dolomite.