Landslides and gully erosion in Jurassic marl-limestone areas (Central Portugal)

摘要

A large amount of evidence of slope instability can be found in Central Portugal, in areas where marl-limestone alternations of the Lower and Middle Jurassic occur. This evidence includes rotational slides in different states of activity, lateral spreads, translational slides, rock falls and debris flows. Gully and rill erosion was also identified in most slope steepnesses associated with a sparse vegetal cover. The main factors triggering this instability are human activity, changes in vegetal cover and land use, and rainfall.