Landslide geohazard mapping in complex terrains

Abstract

The interaction between high relief, steep slopes, heavy precipitation, complex tectonic and geomorphic history, land uses, and the range of surficial deposits and bedrock can produce a variety of landslide types in many regions of the. In this paper, an effective approach is presented for the classification and mapping of terrain and landslide geohazards from stereo-pair air photographs, satellite imagery and benchmarking field studies in a region of mountainous terrain and discontinuous permafrost in Northwest Canada prone to earthquakes, mass wasting, wildfires and sensitive to the impacts of climate change. Digital terrain and landslide hazard maps and their accompanying geodatabases provide essential information for land management decisions regarding construction of pipelines, highways and settlements; evaluation of property rights decisions; extraction of fossil fuels, minerais, aggregates and groundwater; assessments of environmental risk and impact, ecological sensitivity and archaeological potential. GIS maps and geodatabases also provide calibration for future predictive landslide mapping and hazard analyses. Qualitative, semi-quantitative and quantitative analyses of landslide distribution, activity and density maps derived from terrain and landslide inventory geodatabases can improve the understanding of landslide processes in a region. Important outcomes that can be achieved through the use of geoscience databases, landslide hazard maps and related products include the attraction of new investment and reduction of risks for regional development. Outreach initiatives can also increase professional and public understanding and awareness of landslide hazards and related geoenvironmental issues.