| Abstract | Integrated remote sensing techniques are used increasingly in geohazard assessment. As SAR (synthetic aperture radar) images become commonly available, it is essential that these data be evaluated in
terms of the information they can provide for characterizing areas affected by geological hazards. This paper summarizes the utility of remote sensing in geohazard assessment, and presents two case studies in which SAR and TM (thematic mapper) were
used to characterize areas affected by landslides and coastal hazards. Based on the results of these two case studies, a guideline is proposed for the utility of remote sensors for geohazard assessment. In the first case study integrated SAR/TM
techniques were used to identify and classify landslides in the lower Fraser Valley within the Canadian Rockies. The lower Fraser Valley is one of the most strategically important transportation corridors in Canada. Almost all the lifelines that link
the resource rich prairie provinces with metropolitan Vancouver utilize this corridor. Landslides within this valley threaten to disrupt these major transport links. Image maps resulting from the integration of geometrically corrected SAR and TM data
provided information on the geomorphology of slopes, land cover and the location and distribution of fracture zones. Such characterization enables the identification and classification of landslides and will complement current airphoto methods used
for landslide inventories in high relief areas. In the second case study, enhanced SAR and TM integrated techniques using IHS transform were used to locate areas of erosion and deposition and to update current coastal geomorphological and land cover
maps. Coastal Guyana is below sea level, hence sea defence (dykes and sea dams) are used to protect coastal settlements, infrastructure and rich agricultural lands. Erosion of the sea dams has led to severe damage of agricultural lands due to
flooding by seawater. The resultant image maps using SAR/TM integrated techniques assist in monitoring the constantly changing shoreline, enable the assessment of flood damage, facilitate in planning areas for coastal dyke repair and maintenance and
provide new information for the revision of ongoing coastal geomorphological mapping. |