Pustaka Ilmiah Universitas Padjadjaran

Abstrak

Morphotectonic Characteristics Of The Cilangla And Cipatujah Watershed At The Tasikmalaya Regency, West Java

Watershed of Cilangla and Cipatujah area in Tasikmalaya Regency, West Java Province is a part of the Southern Mountain of West Java. West Java is an area of active tectonic and volcanic because it is located close to the collision zone between the Eurasian plate and the Indo-Australia. Tectonic activities at the subduction zone can trigger fault activities on the mainland. The research is aimed to determine the characteristics of morphotectonic and its implications on the structural conditions and the potential natural disasters that may occur in the study area. There are three analysis methods used in the research which are studio, field and laboratory methods. Studio analysis includes morphometric analysis based on mountain-front sinuosity (Smf), ratio of valley floor width to valley height (Vf), and bifurcation ratio (Rb). Morphometric aspects such as dimension and shape of watershed were analyzed by using data extraction from DEM and topographic map. The results of morphometry analysis of the research area show the tectonic influence is difference between Cilangla watershed and Cipatujah watershed. The measurement results of geomorphic index indicate tectonic classified as high and medium grade with Smf values range from 1 to 1.9, while the value of Vf range between 0.2 to 6. The area is covered by old volcanic rocks of Tertiary and Quaternary and Tertiary sedimentary rocks. Watershed of Cilangla and Cipatujah were controlled by the combination between lithology, weathering and active tectonic which allow the ground movement and earthquake that will happened in the future.