The increasing availability and precision of digital elevation model
(DEM) helps in the assessment of landslide prone areas where only
few data are available. This approach is performed in 6 main steps
which include: DEM creation; identification of geomorphologic features;
determination of the main sets of discontinuities; mapping of the
most likely dangerous structures; preliminary rock-fall assessment;
estimation of the large instabilities volumes.
The method is applied to two the cases studies in the Oppstadhornet
mountain (730m alt): (1) a 10 millions m3 slow-moving rockslide and
(2) a potential high-energy rock falling prone area. The orientations
of the foliation and of the major discontinuities have been determined
directly from the DEM. These results are in very good agreement with
field measurements. Spatial arrangements of discontinuities and foliation
with the topography revealed hazardous structures. Maps of potential
occurrence of these hazardous structures show highly probable sliding
areas at the foot of the main landslide and potential rock falls
in the eastern part of the mountain.