Water Stewardship Information Sources

Citation Barlow, J, Martin, Y and Franklin, S. 2003. Detecting translational landslide scars using segmentation of Landsat ETM+ and DEM data in the northern Cascade Mountains, British Columbia. Canadian Journal of Remote Sensing. 29:510-517.
Organization University of Calgary
URL http://bgs.ucalgary.ca/files/bgs/barlow_martin_franklin_2003.pdf
Abstract/Description or Keywords Extensive landslide inventories are often utilized for hazard assessment studies and when investigating mediumto
long-term evolution of alpine terrain. The predominant methodology for collecting these databases is aerial photographic
interpretation, which can be time-consuming and expensive. Earlier work has demonstrated that spectral response patterns
for satellite images, when used alone, are unreliable at detecting most types of landslides. Principal difficulties are related to
inadequate image resolution and spectral methods of classifying image data that are not sensitive to the characteristics that
identify landslide features such as their shape and topographic expression. This study in the Cascade Mountains of coastal
British Columbia attempts to overcome the latter problem through image segmentation and the use of geomorphometric data
derived from a digital elevation model (DEM). Image segmentation involved grouping pixels into discrete objects based on
similarities and differences in their reflectance and the use of shape criteria. A hierarchical classification system was then
developed such that the normalized difference vegetation index (NDVI) and slope data eliminated all areas in the image that
were both vegetated and on a gradient of less than 15°. The remaining “unvegetated steeplands” were classified using a
supervised classification based on spectral, geomorphic, and shape criteria. The technique produced an overall accuracy of
75% in the detection of landslides that were over 1 ha in area.
Information Type article
Regional Watershed Lower Fraser
Sub-watershed if known
Aquifer #
Project status complete
Contact Name John Barlow
Contact Email [email protected]