Landslide hazard zonation mapping using remote sensing and geographic information system techniques-a case study of Pithoragarh area, U.P

To analyze and map landslides, an area near Pithoragarh, U.P. has been selected as a case study. The main sources of the data for this study consists of satellite imagery (IRS-IC and SPOT PLA) and SOI toposheet. Besides, collateral data like geological map and literature on landslides in and around the study area has also been considered. To understand the relationship between landslides and various thematic (data) layers such as geology, land use/land cover, slopes, tectonic elements etc., GIS techniques like overlaying, and visualization have been carried out in ARC/INFO environment. The parameters (9) considered for this case study have different degrees of influence on landslide process. Using an in-house built software “DECISION SPACE”, the impact of each parameter on landslides has been determined. In order to assign weightage to each of these (9) parameters, decision rules such as Analytical Hierarchy Process (AHP) and Factor of Importance (FOI) were applied. To conclude the study, the influence of various landslide initiation parameters can effectively be weighed using the “DECISION SPACE”