Influência do sistema de falhas da barra na ocorrência de movimentos de massa na região metropolitana da Cidade de Salvador, Bahia

Mass movements are recurring and concerning events in Salvador, located in Northeastern Brazil, especially in densely populated urban areas with precarious infrastructure. The city, whose topography is influenced by transverse and longitudinal fault systems, including the Barra Fault System (BFS), faces challenges due to disorganized population growth and climatic conditions. These characteristics result in frequent mass movements, exposing the population and their homes to hazard. Although previous studies have contributed to the understanding of the city's structure, geology, and geomorphology, there is still a specific gap regarding the direct influence of the BFS on the generation and control of mass movements on slopes. This study analyzed the geometric and kinematic characteristics of the BFS, focusing on identifying discontinuities in natural slopes and instability mechanisms, such as planar sliding, wedge sliding, and toppling. The method included the analysis of structural lineaments using Schmidt-Lambert stereographic projection and a survey of morphostructural data to identify potentially unstable areas. The results highlighted that the BFS influences the orientation of critical discontinuities, with greater susceptibility to planar and wedge slides, especially on slopes with intersections of structural families compatible with the fault's direction. A correlation was also observed between areas with a high density of lineaments and a higher incidence of reported landslides. On the other hand, the toppling mechanism did not present critical points of instability in the analyzed scenarios. This study provides technical support for the management of urban and housing infrastructure, in addition to contributing to the implementation of public policies aimed at the safety of the most vulnerable populations in Salvador.