Geology and determination of rock mass strength at Kampung Lubok Bongor, Jeli, Kelantan.

This study is entitled “ Geology and Determination of Rock Mass Strength at Kg Lubok Bongor, Jeli, Kelantan”. The aims of the study are to conduct and produce geological mapping of study area to scale of 1:25,000, and to determine the rock mass strength within study area. The area studied lies between longitude of 1010 51’30’’ E to 101054’0’’ E and the latitude of 5035’0’’ N to 5033’ 0’’ N. The methods used in this study are geological mapping, petrographic studies and statistical analysis. Hornfels outcrop was exposed near TNB mini power station at Renyok waterfall. Biotite granite outcrop was exposed along the slope in the study area including as intrusive veins on hornfels outcrops of Renyok waterfall. The main alluvial sediments are sourced from Pergau river, poorly sorted sediments. For specification, there are four main parameters that were analyzed at the rock mass. They are spacing of discontinuities, infilling material of discontinuities, surface roughness of discontinuities and water condition of the discontinuities. These parameters are elaborated for each selected rock mass within study area. Rock Quality Designation (RQD) is calculated as one of the parameter of Rock Mass Rating (RMR). In conclusion, granite rocks have higher RMR compared to the metasedimentary rock. Granite rock can be classified as good rock meanwhile the metasedimentary rcok can be classified as fair rock.