Geochemical Properties of Landslide Materials, West Sinjai District, South Sulawesi Province

Malino - Sinjai road section is the main access connecting Sinjai and Malino, the mountain tourism destination. As a tourism destination, the access road to the Malino area frequently experiences landslides, especially in the rainy season. The area consists of volcanic rocks that are highly weathered. Some factors controlling the landslides are the expansive mineral contents, steep slopes, and human activities. A further detailed study of soil characteristics is needed to mitigate the area. Grain size distribution and soil geochemical analysis are conducted on landslide and non-landslide materials. The grain size distribution denotes poorly sorted distribution at the scarp and head zone. Meanwhile, it is well sorted in the body and foot zone. The particle size distribution is dominated by medium – fine-sized sand ranging from 30% to 67%. Montmorillonite develops at the foot zone (41%) but is limited at the scarp zone (1,4%) as an expansive clay mineral well. In contrast to that one, vermiculite well develops at the scarp (24,8%), but it restrictedly presents at the foot zone (4,8%).