Landslides Zonation Hazard: relation between geological structures and landslides occurrence in hilly tropical regions of Brazil

Abstract

This paper presents a new approach of landslides zonation hazard studies, based on an integrated study of structural data along with geomorphological and external factors, in a hilly regions of Brazil, covered by a tropical humid rain-forest, called Serra do Mar. The Serra do Mar consists of a hilly region along the east coast of Brazil, with high slopes and many geological structures in a gneiss -migmatitic terrain. In contrast to traditional approaches, this method proposes that structural data (foliation, fractures and bedding planes) and its relation with the slope geometry, is important to be consider in the landslide zonation hazard, along with declivity, relative relief, soil and rock properties, land use and vegetation cover and hydrogeological and climate factors. Results show that slopes with high hazard have the same dip direction of geological structures. Landslide zonation hazard using structural data contributes to a better understanding of how these structures, preserved in tropical residual soils, influence on slope stability and generates landslides.

A comparative geological, tectonic and geomorphological assessment of the Charlotte, Regent and Madina landslides, Western area, Sierra Leone

“…Research has also revealed that landslide occurrence can be closely connected to anthropogenic factors (e.g. deforestation, slope undercutting and construction) (Skilodimou et al, 2018;Cui et al 2019;Jin et al 2020), and geological structures (Cerri et al 2017).…”

Análise da influência de atributos fisiográficos e morfométricos na definição da suscetibilidade de bacias hidrográficas à ocorrência de corridas de massa

“…Com base nas análises dos escorregamentos, observou-se que encostas com direção e direção de inclinação paralelas ou subparalelas às estruturas geológicas (NE-SW e ENE-WSW, principalmente), tornam muito suscetível a ocorrência de escorregamentos (e.g., Cerri et al, 2017). Isso, com a potencialidade de ocorrência de corridas de massa, deve ser considerado, uma vez que escorregamentos são importantes fontes de materiais para as corridas de massa de origem primária e, quando somados aos sedimentos e materiais depositados nos canais de drenagem, são fontes para as corridas de massa de origem secundária.…”

Assessment of landslide occurrences in Serra do Mar mountain range using kinematic analyses

“…Many studies have attempted to understand the dynamics of Serra do Mar landslides (e.g. Furian et al 1999;Seluchi and Chou 2009;Vieira et al 2010;Dias et al 2016;Cerri et al 2017). However, none of them investigated deeply the role of geological discontinuities, even though Serra do Mar presents a notorious structural control (e.g.…”