Análise geomorfométrica da região da folha Capão Bonito (SG-22-X-B-III), SE do estado de São Paulo: Implicações neotectônicas na porção sul da Serra de Paranapiacaba e Gráben de Sete Barras

The Southeastern region of Brazil, at the Atlantic border, is known for the existence of a regional scale range named Serra do Mar. This geomorphological feature extends for approximately 1000 km at NE-SW direction, from the state of Rio de Janeiro to the state of Santa Catarina. It divides two very distinct geological and geomorphological environments - at East, the coastal plains, covered by quaternary shallow marine sediments - and at West, the higher grounds of the Plantalto Atlântico, composed by the metamorphic rocks of the Ribeira fold belt and its granitic intrusions. At the study area the segment of the Serra do Mar is known as Serra de Paranapiacaba. It is a very steep scarp with heights reaching 850 m and is the northern border of a small rift basin known as the Guapiara Graben, dimensioning about 20x5 km. Evidences of neotectonic events related to the uplift of Serra do Mar Range and to the tafrogeny of the Continental Rift of the Southeastern Brazil are being studied at this work through the application of geomorphometry, mainly concerning the isobase method, interpreted along with other DEM treatment methods. The results suggests that the neotectonic movements at the area occur due to reactivation of ancient structures during the late paleogene, i.e.: the regional foliation of the metamorphic rocks from the Proterozoic (NE-SW) and a perpendicular series of structures NW-SE called the Guapiara Lineament, dated from the late Jurassic.