Susceptibility to the Occurrence of Mass Movements in Baturité Massif - Ceará, Brazil

Abstract

Studies of mass movements are very important for understanding the geomorphologic evolution and identifying morphodynamic risk areas. The Baturite massif presents itself as the most significant wet hill of Ceará. Its average altitude is around 800m, and may have ridges above 1,000 m. From the geomorphologic point of view, there is a wide variety of features such as reliefs dissected on the hillsides, interspersed rolling hills with the deposition plains and surfaces of erosion and deposition in the lower surrounding areas. The distribution and characteristics of mass movements vary according to the properties of each area. Mass movements have been identified only in the areas with the most significant slopes, which are essentially found in uphills and in the plateau. In general, it was observed the occurrence of rotational and translational landslides associated with mud flows and falls. Considering the need to develop mappings aimed at identifying areas of morphodynamic susceptibility, methodological criteria involving the triggering agents using techniques of maps algebra were established. As a result, we identified areas with high susceptibility, in the western and southern hillsides and part of the eastern areas, with average susceptibility in other sectors of the uphill and low susceptibility in the surrounding areas.