LANDSLIDE HAZARD ZONATION ALONG STATE HIGHWAY BETWEEN AIZAWL CITY AND AIBAWK TOWN, MIZORAM, INDIA USING GEOSPATIAL TECHNIQUES

Road transport network is one of the most common victim of landslide disaster which inturn affects the population. Landslide is one of the most common geo - environmental hazards in Mizoram due to its fragile geologic conditions and unplanne d developmental activities. The present study investigates the Landslide Hazard Zones along State highway between Aizawl city and Aibawk town of Mizoram. This highway is the most important road connecting northern and southern parts of the state. The study utilized Remote Sensing and Geographic Information System (GIS) techniques. The road was buffered 50m on both side to delineate the study area. Important factors which induced landslide were identified and accordingly, five thematic layers viz., slope mor phometry, geological structures like faults and lineaments, lithology, relative relief and land use / land cover were generated. These thematic layers were ranked and weighted based on their relative importance in causing landslide. Each class within a the matic layer was assigned an ordinal rating from 1 to 10 as attribute information in the GIS environment. These attribute values were then multiplied by the corresponding rank values to yield the different zones of landslide hazard. The ground information o n landslide occurences were also considered while classifying the different zones of landslide hazard. The resulting Landslide Hazard Zonation map classified the area into five relative hazard classes like very high, high, moderate, low, and very low. The final map generated will, therefore, be used by engineers and administrators for maintenance and monitoring of this state highway to ensure smooth flow of transportation between the state capital and other important district headquarters of the southern pa rt of Mizoram. Landslide inventory was also conducted and remedial measures were suggested at several landslide locations.