Application of remote sensing and Gis for land slide hazard Zonation of Kadanadu, Nilgiri district, Tamilnadu state

Landslide is typically defined by a wide range of ground movement, such as rock falls, deep failure of slopes, and shallow debris flows. Landslide hazard results in great loss of life and property. These damages can be avoided if the cause and effect relationships of the events are known. Landslides are frequent and annually recurring phenomenon in the Nilgiri district. High intensity rainfall triggered most of the landslides in the Nilgiri district. As long as landslides occur in remote, unpopulated regions, they are treated as just another denudation process sculpting the landscape, but when occur in populated regions; they become subjects of serious study. The study area Kadanadu is a part of the Nilgiris District located between 11°35 N and 11°58N latitude and between 76° 74 E and 77° E longitude. The study area falls in the Survey of India Toposheets 58A/11, 58A/14, 58A/15, 58E/2, 58E/3 in 1:50,000 scale. It covers an area 398.483sq.km.The present work is an attempt towards application of GIS for landslide vulnerability mapping. Different thematic layers have been prepared such as geomorphology, lineament density, drainage density, slope, soil depth, and land use. The numerical weights of the categories of the factors have been determined using subject knowledge