MAPPING OF LANDSLIDE USING TERRESTRIAL PHOTOGRAMMETRY

Abstract

Landslides are sudden, short-lived geomorphic events that involve the rapid-to-slow descent of soil or rock in sloping terrains that occur worldwide. Globally, landslides cause billions of rupees in damage and thousands of deaths and injuries each year. Identifying the potentially hazardous areas and carrying out preventive measures such as tree plantations in such areas can reduce the risks due to landslides. Hence landslide mapping is important. In the past surveying techniques have often proved difficult and expensive because of the inherent problems associated with the wide areas and dynamic processes in the landslide areas, Most of the time, the areas are inaccessible. The spatial resolution of satellite data is generally considered too coarse to accurately map landslide features on a large scale. The problem with aerial photography is that the data is not readily available and its acquisition is a tedious process. Terrestrial photogrammetry has an edge over aerial photogrammetry in terms of the ease of data collection. Photographs can be acquired at any time and any where by using easily available instruments like a metric camera. Hence terrestrial photogrammetry is gaining wide acceptability through out the world. In the present study mapping of Patalganga landslide was done using terrestrial photogrammetry. The photographs of the landslide area were acquired using a metric camera (Rolliflex 6006) and control points were measured using a total station (Trimble). This data was imported in Geomatica V.9.1.3 OrthoEngine Module and analysis was carried out. Finally the contour map was generated and details were plotted.