Tectonic Geomorphology of Escarpment In Yogyakarta And Surrounding Area

• Main Author: , D. H. Barianto.
• Format: Article NonPeerReviewed
• Published: [Yogyakarta] : Departemnts of Geological Engineering Faculty of E 2009
• Online Access: https://repository.ugm.ac.id/95174/; http://repository.ugm.ac.id/digitasi/index.php?module=cari_hasil_full&idbuku=2992
• Institution: Universitas Gadjah Mada

<p>This research tries to find the faults that have potentials being active faults by'. using morphotectonic approach. The data used are topographic map and height point (interval 6.25 m), Landsat TM, Geological Map, and compilation fault map. All data are combined and analyzed by using GIS. This analysis comprises geomorphic indices that have been used successfully in studies of active tectonics, as the mountain front sinuosity index (Smt), stream gradient index (SL) and valley floor width to valley height ratio (Vt). There were six faults being analyze, i.e. Menoreh, Ijo, Prambanan-Bayat, Nglipar, Sampang and Opak- Siluk faults. These faults are the primary faults that control the morphology around Yogyakarta graben. The SL value shows all mountains front have a break of slope that is controlled by the fault. Based on the Smf and Vf value, almost all of the faults that control the formation of the fore mountains are active faults. The active faults were pointed out in class I in which the Smf value would be less than 1.5. It appeared that almost all faults are in class I except for the Prambanan-Bayat fault. However, the Prambanan-Bayat fault cannot be categorized as class 2. This shows that the tectonic is very dominant in the shaping of the slope mountain. Therefore, we can interpret that almost all of the faults analyzed have the potential to be active faults.<br /> I. Staf of Geological Engineering Dept., Faculty of Engineering, Gadjah Mada University, Indonesia and student at Dept. of Earth Resources Engineering, Kyushu University, Japan.<br /> 2. Staf of Geological Engineering Dept., Faculty of Engineering, Gadjah Mada University, Indonesia and student at Dept. of Civil and Environmental Engineering, Kyushu University, Japan.<br /> 3. Professor at Dept. of Earth Resources Engineering, Faculty of Engineering, Kyushu University, Fukuoka, Japan.</p>