Kajian Tingkat Perkembangan Tanah pada Kejadian Bencana Longsor Lahan di Pegunungan Menoreh Kabupaten Kulonprogo Daerah Istimewa Yogyakarta

Abstract

The obj ective of this first phase study was to k now the landforms characteristic at landslide occurrences in the research area.This research con ducted with the field survey on landforms ph enomena at the location of landslides occurrences. Landforms map was constructed from topog rap hic map , geology map , and assisted by an alysis Digital Elevation Modeling ( DEM).The result shows that the research area has 14 landforms u nit by 161 land slides o ccurrence. Landslide occurrences at the mou ntains of denudationa l of Formation Bemmelen (49 occurrences), in the mou ntain of intrusive andesitic ( 34 occurrences), and the foot-slop e mou ntain of denudational of Formation Be mmelen ( 18 occurrences). The level of landslide vulnerab ility is distinguish ed by existence of progressively increased weathering zone an d rock structure which pa rallel with the level inclina tion of the main slope.