CODIGO PONENCIA : 20111715BQAHUB TITULO PONENCIA : CATEGORIA PONENCIA : Póster CLASIFICACION TEMATICA : Geografía aplicada AUTOR PRINCIPAL : LISBOA SIMONE ORGANIZACION : UFRJ PAIS : Brasil / Brazil GEOMORPHOLOGICAL EVOLUTION AND DRAINAGE REARRANGEMENT IN SOUTH COAST OF THE STATE OF RIO DE JANEIRO - BRAZIL Simone Lisboa dos Santos da Silva (Doutoranda do Programa de Pós-Graduação em Geografia/UFRJ; [email protected]) Telma Mendes da Silva (Profa. Adjunta IV; Depto. Geografia/IGEO-UFRJ; [email protected]) From the geomorphological viewpoint, the south coast region of the state of Rio de Janeiro presents a configuration wich favors the development of a rich drainage network, since it conjugates a relief contrastant – with predominance of mountains features in abrupt contact with fluvial and/or fluvial-marine plains quaternary morphologic features, typical of the coves located in Angra dos Reis Bay in south coast of the state of Rio de Janeiro. This area has high pluviometric index, providing high dynamics as regards morphodynamics processes, considering that drainage systems are basic elements of relief dissection, erosion and materials transport. Such, the contrast between the declivities of morphological features added raised pluviometric index, and a flat weathering mantle on impermeable rocky bodies, that produces a hydrodynamics discontinuity between these materials, favor raise taxes of superficial and subsurface draining on slopes that produces full flood events in the valley floor segments, and they can lead to an intense materials transport. These local natural conditions and the disordered occupation process in this city, i. e, without provisions adequate of pluvial waters networks and sewerage system, aggravate the environment instability scenery. In the study area there are registers of litho-structural control in drainage systems and local morphology, which are associated to occurrence of gravitational movements and transport mass processes (SILVA Jr., 1991; FERNANDES; 2010), it takes to believe that the drainage network extensive in this area has dynamics intense of rearrangement at fluvial systems, both geological and historical scales. For study area Silva (2002) realized a mapping of morphologic units in semi-scale detail (1:50.000), at which it recognized hills, mountains and steep mountains morphologic features and transition areas and/or features between different morphologies, however it becomes necessary an analysis more refined and mappings in more detailed scales for corresponding area to Rio Mambucaba, Cunhambebe, Mangaratiba, Parati, Angra dos Reis and Ilha Grande topographic letters aiming more representative mapping of local morphologies, as searching to understand dynamics evolutionary of themselves. Thus, from these proposals it is justified necessity of better understanding local dynamics evolutionary, and we think that identification, characterization and analysis of possible drainage rearrangement in south coast of the state of Rio de Janeiro represents an efficient approach for establishment of a geoenvironmental compartmentalization for this area, aiming to, especially, planning and strategical handling of risks associates to the natural conditions. The analyses preliminarily carried had allowed to identify the existence of a bigger number of canals of first and/or zero orders, that can be articulated to occurrence of recent geomorphological processes and that, therefore, it contributes as basic information for the understanding of the current landscape evolution. In this direction, the present work presents the initial stages of the Doctorate of Geography that aiming to besides geoenvironmental compartmentalization for study area (considering litho-structural influence, climate regimen and vegetal covering), it proposes anomalies drainage identification in 1:50.000 scale, analyzing neotectonism evidence and using themselves as main evidence for rearrangements drainage of these systems; through: a) elaboration topographic and relief profiles, using methodology proposal for Meis et al. (1982); b) drainage lineaments mapping, which will server for the analysis and interpretation of the main drainage directions, that crossed with basement structural directions will allow to verify the geologic structures influences at morphodynamic; c) morphometric analysis applying the Factor Asymmetry of the Basin of Drainage (FABD) and Factor of Transverse Topographical Symmetry (FTTS). References FERNANDES, N.F. 2010. Palestra proferida no Seminário “Ilha Grande: Aspectos Geomorfológicos e Uso/Ocupação do Solo”. Clube de Engenharia – CREA/RJ. Janeiro de 2010. MEIS, M.R.; MIRANDA, L.H.G. e FERNANDES, N.F. 1982, Desnivelamento de altitude como parâmetro para a compartimentação do relevo: bacia do médio-baixo Paraíba do Sul. In: Congresso Brasileiro de Geologia, 32, 1982, Salvador. Anais... Salvador: SBG. 4:1489-1509. SILVA Jr., G.C. 1991. Condicionantes Geológicos na Estabilidade de Taludes ao Longo da Rodovia BR-101 no Trecho Itaguaí – Angra dos Reis. Rio de Janeiro, 172 p. (Dissertação de Mestrado, Depto. Geologia/IGEOUFRJ). SILVA, T. M. 2002. A estruturação geomorfológica do Planalto Atlântico no Estado do Rio de Janeiro. Rio de Janeiro. 2002. 265p. Tese (Doutorado em Geografia) – Instituto de Geociências, Universidade Federal do Rio de Janeiro, RJ.