ABSTRACT

The purpose of this study is to investigates and demonstrates the state of Remote sensing techniques for detailed landslide hazard assessment applicable to large areas. So this study using CARTOSAT-1, a high resolution imagery because the common methods of landslide susceptibility assessment using weighted overlay are heavily dependent on 3-dimentional terrain visualization and analysis stereo satellite image. CARTOSAT-1, digital photogrammetric and GIS (Geographic information system) are very useful application that used in terrain mapping purpose, increased the demand of maps in various sectors such resource management, engineering sectors in planning and developmental purpose.

Digital Elevation Models is very useful for height information, such as the availability CARTOSAT-1 has opened new possibilities for terrain parameter evaluation. CARTOSAT-1 providing high resolution (2.5 m) Stereo imagery of the earths surface. DEM also used for evaluating the terrain parameters such as elevation, slope, contour, drainage pattern, and thematic maps of geology and geomorphology lineament land use and soil map. These parameters are required as input to applications such as landslide susceptibility analysis.

Landslide susceptibility map will provide guidelines to assess the spatial distribution of potential landslide by identified landslide prone area and validate previous landslide location. This landslide susceptibility information should provide have useful new tool for study and evaluation of landslide occurrence.INTRODUCTION

Digital Elevation Model (DEM) is needed for some analyses such as tophographic extraction, earth relief analysis, landslide susceptibility analysis, etc. before using DEM, we need to know the accuracy of DEM itself first. The accuracy of DEM is usually represented by the spatial resolution and height. DEM doesnt contain civil information such as roads, or building. DEM also doesnt contain elevation contours, it only contain the specific elevation elevation values at specific grid point location.

This journal is specifically show the use of DEM in landslide analysis. Landslide itself is one of the major geo hazards, it always caused a major problem by killing hundreds of people every year, beside that landslide itself can also damage the properties and block the communication links. The most useful direct indicators of landslide susceptibility are considered to be evidence of past landslindes as well as tension cracks and other detectable earth movement. Based on premises, area with past landslides has a high probability of having a new landslides.

DISCUSSIONDigital Elevation Model is useful for height information and also for extracting terrain parameters. The used of DEM is depends on the accuracy of the DEM. The comparison of the ground height generated by DEM as well as ground heign information collected in this journal. It was showed that DEM generated from Cartosat -1 strero data will be very much useful for topographic analysis in the field of water resources, agriculture, and landslide analysis.

Evaluated the effectiveness of a landslide susceptibility map derived from four topographic parameters (elevation, slope angle, curvature, and aspect). The spatial relationship between landslide-occurrence and factor influencing landslide are assessed. Landslide susceptibility map will provide guidelines to asses the spatial distribution of potential landslide by identified landslide prone area and validate previous landslide location.

There are basically 2 different ways to determine the weights for the various categories causative factors. The one is based on subjective approach where a person assigns weights based on expert opinion or his own experience on the subject and the area (Anbalagan 1992, Sarkar and Kanungo 2004) and the other is an approach where factors are correlated with existing landslides.

The primary terrain parameters are those that can be derived directly from the DEM. The morph metric terrain parameters are elevation change gradients (slope); orientation gradients

CONCLUSION

DEM is very useful for many analyses such as topographic feature extraction, runoff analysis, landslide susceptibility analysis, etc. But the accuracy must be discussed, because there is may an error in height range 0,5 m. DEM also does not contain civil information such as roads or building but contain the specific elevation values at specific grid point location. From this point, DEM is very useful to identify landslide, one of the major geo hazards that cause a major problem by killing hundreds of people every year, damaging the properties, and blocking the communication links.

Landslide caused by many factors, such as terrain, extreme rainfall, or tectonic movements. And it can increase due to human activity such as deforestation or urban expansion. But all of these hazard could be identified by DEM generated from CARTOSAT-1, and GIS that could perform the spatial data.