Mapping of Geological Structures: Potential Geohazards in Tropical Highlands

Abstract

Landslides in tropical hilly terrain have become a threat to the community. The difficulty of predicting future landslides can be overcome by detecting signs of past landslides especially in tropical hilly terrain like Cameron Highland, Pahang Darul Makmur. Basic skills in geomorphology and remote sensing are needed in detecting and mapping past landslides due to its geomorphological features that have been modified because of erosion, weathering, and development. However, an approach by using remote sensing and Geographic Information System techniques, the detection of geomorphological features can be done. Among the features that can be seen is hummocky topography, existence of articulating head scarps, crowns, main scarp, side scarps and convex hillslopes followed by concave hillslopes. The activation of inactive landslides is usually caused by natural factors and human factors. Natural factors consist of high rainfall distribution which weakens the soil structure and causes physical and chemical weathering process or rate to increase. About 40% of slopes in the study area with the steepness of 25° which is identified as the main natural factor to slope failures. Human factors comprise of the construction of permanent and large-scale infrastructure which exerts load hence weakening the slope strength. This causes a growth of tension cracks which are perpendicular to the slope face and is expanding up to this day.