LANDSLIDE ANALYSIS & SUSCEPTIBILITY MAPPING BY USING GIS IN BAO LOC MOUNTAIN PASS, LAM DONG PROVINCE, VIET NAM
| Main Authors: | , LE THI THU HA, , Prof. Dr. Dwikorita Karnawati, M.Sc., Ph.D. |
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| Format: | Thesis NonPeerReviewed |
| Terbitan: |
[Yogyakarta] : Universitas Gadjah Mada
, 2011
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| Subjects: | |
| Online Access: |
https://repository.ugm.ac.id/89970/ http://etd.ugm.ac.id/index.php?mod=penelitian_detail&sub=PenelitianDetail&act=view&typ=html&buku_id=52328 |
Daftar Isi:
- National way 20, situated in Bao Loc mountain pass, Lam Dong provine, is one of the most important ways which connects Da Lat city to Ho Chi Minh city, Viet Nam. Most of the study area covered by weathering zone of extrusive rock (i.e. Andeiste) of Deo Bao Loc formation which is very susceptibility to landslide occurrence. Landslide occur frequently in the area and seriously affect local living conditions, irregularly concentratied in August, September and Octorber when the total rain precipitation reaches 400mm in one month. Therefore, spatial analysis of landslide susceptibility in the mountainous regions of the Bao Loc is very important. Hence, this study focuses at a particular mountainous region of about 10 km along national way 20. The research is aimed to develop landslide susceptibility mapping at 1/50.000 scale by Geographic Information System (GIS) with SINMAP method which is consider the susceptible landslide area with the various degree of susceptible. Data collection, site investigation and other work were performed to indentify the condions of geomorphology and geology, contributing to landslide occurrences in the area. To develop landslide susceptibility map by SINMAP model, some input parameters were selected and prepared such as topography slope, specific catchment area, geological parameter (soil cohesion, root cohesion, friction angle, soil depth..), hydrological parameter (rainfall). The topography slope and specific catchment area are autormatically computed from digital elevation model (DEM) are. The other input parameters are recognized to be uncertain so are specified to SINMAP in terms of upper and lower boundaries. In the study area, two calibration regions which are the weathering zone on extrusive rock (i.e. andesite) and weathering zone on intrusive rock (i.e. granite) were chosen on the basic of rock type. Two main analysis scenarios which have maximum rainfall (17,2mm/day) and minimum rainfall (11,4mm/day) are applied to analysis stability index. The results were classified into six stability index classes. There are: stable (SI>1,5), moderately stable (<1,25<SI<1,5), quasi stable (1<SI<1,25), lower Landslide analysis and susceptibility mapping by using GIS in Bao Loc mountain pass, Lam Dong province, Viet Nam Page iv threshold (0,5<SI<1), upper threshold (0<SI<0,5) and defended (SI=0). Based on SI result, the final landslide susceptibility map of the study area in two scenarios were developed and it delineates the area into different zones of four relative susceptibility classes: none to low (SI>1,5)