Correlation of Some Engineering Geological Properties of the Murree Formation at Lower Topa (Murree District), Pakistan
Abstract
Uniaxial Compressive Strength, Young's Modulus, Point Load Strength Index, Schmidt Rebound Hammer Number and Matrix (calcitic as well as clayey) are correlated for 90 samples (30 from each lithology of alternating sandstones, siltstones and claystones) to determine the effect of lithological boundaries and that of the cementing material. Correlation Coefficients of different combinations of Strength, Young's Modulus and Schimidt Hammer Rebound Number were determined. Similarly, various combinations of mineral assemblages and matrix with clasts and lithological position of samples were tried and compared with strength. It is observed that strength is not only variable in each lithology but also changes with position of sample with reference to the upper or lower lithological boundaries. Laboratory tests on cores seem to be imperative for supplementing the field index tests on such detritus materials.
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