General geology and landslide investigation using resistivity of Pos Blau- Gua Musang Road, Kelantan

Landslide is a one of common natural hazard that cause the loss of human lives and damage to infrastructure. Landslide occurs frequently at Gua Musang- Cameron Highland road including at Pos Blau area. The objectives of this study are to update the geological map of study area, to determine the type of landslide occur in the study area and to investigate the subsurface landslide by using electrical resistivity image method. All the objectives are choosing because of the geological map of study area is not updated according to current situation and there is no previous study about landslide subsurface investigation at study area. Geological field mapping is done by collecting general geology information including lithology, structural, geomorphology and stratigraphy of the study area. The geological map is updated by using ArcGis software. While for landslide subsurface investigation is done by using ABEM Terrameter LS to show the result for electrical resistivity imaging. Geological data from field observation were analysed by using rose diagram and stereonet especially in structural analysis. Petrography in observing mineral composition was used to determine the type of lithology. Resistivity data analysis is conducted by RES2dinv software that produced a good quality pseudosection image. Based on field mapping, there is new discover type of lithology present at study area which is lapilli tuff from one of the igneous rock type. In structural, minor recumbent fold and anticline fold also found with reverse fault. So the geological map of study area had been updated according to all this geological information. ERI profile for resistivity survey divides into two lines which are horizontal and vertical. Both were carried out at same location but differ by the type of array. Both interpretations are based on zone show some similarity for the possibility type of lithology in subsurface. Because of high amount of weak zone for both profiles, it can be conclude that weak zone as the main trigger of landslide occurrence at study area.