Aplicação dos métodos gravimétrico e magnetométrico para a definição do comportamento estrutural da faixa de dobramentos Araguaia

O presente trabalho consiste na interpretação de informações gravimétricas e aeromagnetométricas (Projeto Geofísico Brasil-Canadá - PGBC) da região setentrional da Faixa de Dobramentos Araguaia, envolvendo uma área de aproximadamente 129.000km², compreendida entre os meridianos 47°50’W e 50°30’W e paralelos 4°50'S e 9°00'S. Abrange porções sudeste do Estado do Pará, noroeste de Goiás e oeste do Maranhão. Os trabalhos de campo constaram de levantamentos gravimétrico e altimétrico, ao longo de rodovias que constituem a rede viária regional, e os resultados obtidos, após correções e reduções, foram então organizados de forma a constituírem um mapa de anomalias Bouguer, apresentado em escala 1:500.000. O padrão gravimétrico da faixa de dobramentos Araguaia se caracteriza por mostrar feições predominantemente longitudinais, com curvas isoanômalas de direções submeridianas, concordante com o comportamento litológico-estrutural conhecido para a área. Na porção centro-meridional desse mapa aparece uma zona de anomalia negativa, alongada e intensa (menos de -100mgal), a qual sofre duas importantes inflexões para NW, sendo uma correlacionável ao Lineamento Carajás, e a outra na altura do paralelo 5°30'S. Apresenta zonas de altos gravimétricos, notadamente na porção noroeste (domínio cratônico), relacionada à influência das metavulcânicas do Grupo Grão Pará, e na porção nordeste, devida a massas densas introduzidas na crosta. Destaca-se também o relativo alto gravimétrico acompanhando o flanco oriental do eixo de ocorrência das braquidobras, podendo ser devido a massas excedentes colocadas sob essa região, através de esforços tectônicos, produzindo elevações do nível de base da crosta e consequentemente do embasamento. De forma genérica o flanco oriental da faixa mostra um gradiente mais intenso que o ocidental, devido principalmente à configuração geométrica das estruturas nesse setor. Da mesma forma merece destaque o gradiente regional ascendente de sul para norte. A análise das cartas de intensidade magnética do PGBC fornecem condições à individualização de diversos domínios magnéticos, perfeitamente correlacionáveis litológico e estruturalmente com as unidades geotectônicas que compõem o arcabouço regional, assim como suas subunidades. A execução de modelamento simples, quer para as informações gravimétricas como magnetométricas, objetivaram fornecer subsídios semi-quantitativos à interpretação, de forma a auxiliar no estabelecimento do padrão geométrico do embasamento da faixa de dobramentos Araguaia, assim como das estruturas a ela impostas. Assim, por meio do processamento das informações gravimétricas, verificou-se um padrão geométrico na forma de fatias imbricadas, estabelecidas sobre o substrato. A grande anomalia negativa da porção centro-meridional da faixa pode estar relacionada a uma deficiência de massa profunda (depressão na base da crosta) ou ainda a uma associação entre contraste de densidade e espessamento do pacote de supracrustais, nessa porção. O baixo gravimétrico da porção sudeste da área, entre Guarai e Tupirama, é devido a uma depressão do embasamento, da mesma forma como a anomalia negativa associada ao Lineamento Carajás está relacionada a uma estrutura sinformal conhecida.

CALIBRAÇÃO E VALIDAÇÃO DO ÍNDICE DE ESTABILIDADE DE ENCOSTAS COM INVENTÁRIO DE ESCORREGAMENTOS

A ocorrência de escorregamentos translacionais no litoral paulista é parte integrante da evolução natural das encostas, que se intensifica sob condições de clima tropical em uma morfologia de serras com desníveis em torno de 700m. Sob precipitações intensas, mesmo sem a interferência direta do homem, os movimentos de massa ocorrem de forma isolada ou generalizada, como a centena de escorregamentos registrados no evento de janeiro de 1985, em que os índices pluviométricos atingiram 210 mm em 24 h. Utilizando um inventário de cicatrizes de escorregamentos obtido de um aerolevantamento de agosto de 1985, definiu-se como objetivo calibrar e validar um mapa de índice de estabilidade utilizando o modelo de análise de estabilidade de encostas por talude infinito, disponível no programa SINMAP, na Serra de Cubatão, na escala 1:10.000. O modelo foi aplicado considerando os parâmetros do solo constantes para toda área e também variáveis em função das unidades litológicas. Os resultados mostraram que mais de 79% das cicatrizes ficaram dentro dos limites inferior de estabilidade e superior de instabilidade para o caso de parâmetros constantes e mais de 95% das cicatrizes para o caso de parâmetros variáveis dentro dos mesmos limites. Palavras-chave: Índice de estabilidade, movimentos de massa, Serra do Mar.

ANÁLISE FISIOGRÁFICA APLICADA À ELABORAÇÃO DE MAPA GEOLÓGICO-GEOTÉCNICO DE REGIÃO DA SERRA DO MAR E BAIXADA SANTISTA

O objetivo principal do presente artigo corresponde em apresentar o mapa geológico-geotécnico em escala 1:50.000, bem como a caracterização das unidades correspondentes, de uma área, aproximada, de 480 km² na Serra do Mar e na baixada Santista (proximidades dos municípios de Cubatão e Santos, SP). O mapa geológico-geotécnico foi elaborado a partir da união do mapa de unidades de compartimentação do relevo, mapa geológico e das informações obtidas na pesquisa bibliográfica. Neste mapa são apresentadas 15 unidades geológico-geotécnicas, as quais são distribuídas segundo as áreas do Planalto Paulistano (3), a Serrania Costeira (6) e Baixadas Litorâneas (6). Palavras-chave: mapa geológico-geotécnico, análise fisiográfica, meio físico, Serra do Mar e Baixada Santista.

Análise termodinâmica, termoeconômica e econômica de uma usina sucroalcooleira para diferentes mix de produção

Pós-graduação em Engenharia Mecânica - FEIS

Mapeamento geoambiental de Espírito Santo do Pinhal e Santo Antônio do Jardim (SP)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Caracterização gfeológico-geotécnica aplicada a gestão de risco no gasoduto GASBOL, trecho Ipeúna/SP - Itirapina/SP

The pipelines are characterized by the great length and linearity, these enterprises are usually associated with the horizon of soil and decomposed rock and accidents in this system usually have high complexity. So this work proposes a study of geological and geotechnical characterization of approximately 40 km ² and a study of risk analysis along 18.3 km of gas pipeline GASBOL, in the municipalities of Ipeúna-SP and Itirapina-SP, in scale 1:25.000, besides correlation between studies. The method for geological and geotechnical characterization is based on physiographic integrated analysis technique, which is supported by literature research, observation and interpretation of satellite imagery (photointerpretation), correlation of products numerical model of ground, fieldwork. The method adopted for risk classification is based on preliminary analysis of hazards (APP) technique, which is identified the geological process, this feature is classified as the susceptibility of occurrence, and then classified as the possible consequence of the process, if this evolves. As a product of the research, we designed a map in 1:25,000 scale, containing a table of geological and geotechnical characteristics of the mapped drives, as well as sectorization risk in each section of the pipeline. Were mapped geological and geotechnical seven units in the study area, delimited in excerpts of which five are classified as high risk, totaling 1.1 km in length of 18.3 km total

Caracterização metamórfica do Greenstone Belt de Guarinos - GO

The study area comprises Guarinos Greenstone Belt which is located in the centralwest state of Goias and has an approximate size of 280 km2. The present work has as main objective to characterize the metamorphism of the greenstone belt and the relationship between the tectonic events and the metamorphism. For the execution of the work we used data collected in the course Geological Mapping of Crystalline Area of the geology course of UNESP, classes 2009 and 2010, the data collected by Alex Choupina Joaquim Andrade Silva in his master's thesis and the information collected in field in the study area. This compilation of data allows approximately 200 thin sections have been evaluated and allowed the construction of the metamorphic map in scale 1:125.000, also allowed the preparation of the geological map in scale 1:125.000 greestone belt, based on 1:25.000 scale maps performed by students of UNESP and the mapping conducted by Silva (2011). The study area was divided into two tectonic compartments depending on the Shear Zone Engenho Velho that longitudinally crosses study area, with direction approximately NW-SE. The west compartment is bordered by granite-gneiss complex and the east compartment, seems thicker to the south and narrows gradually towards the north and its structure is seen in general as a great monoclinal with NW-SE direction with trim to SW, this way your stack was considered as a package of rocks at the base and metaultramafic metamafic the top, with a second package in tectonic contact, which is composed of detrital and chemical metasedimentary rocks. The east compartment is represented by the intrusion of a large granitic body surrounded by amphibolites and metasediments, is bounded on the east by a granite-gneiss complexes through thrust fault, and is bounded on the west by the other compartment. The structure of the compartment is seen as a major axis oriented roughly... (Completo abstract click electronic access below)

Auxílio do geoprocessamento para a geração do mapa de suscetibilidade à erosão: o caso do córrego Mandu, Rio Claro/SP

The mining of sand, currently, is essential for urban growth, by providing input for the building industry. The consequences of this mining activity to environmental triggers may be severe and irreversible. Among the major impacts caused by sand mining the riparian vegetation removal is detached. The riparian vegetation is essential for balance and maintaining the local ecosystem. For all that had been shown, is possible to verify the importance of environmental studies in areas wich there are mining. This study aimed specially to assess environmental impacts triggered by a mining, located near the headwaters of the stream Mandu, situated in Ajapi, District of Rio Claro-SP. For this purpose, we used remote sensing techniques and GIS to produce thematic maps of slope, pedology, geology, land use and occupation of the soil, and riparian vegetation, using the capabilities of GIS / ArcGIS. The slope map was based on data from the Cartographic IGC 1979, scale 1:10,000. For the production of pedological and geological maps were used Semi-Detailed soil survey of the state of São Paulo, 1981 (1:100,000) and the Geological Map of Zaine (1994), scale 1:50,000, respectively. Since the maps of Use and Land Occupation and Riparian Forest were obtained by visual interpretation of the image of CBERS 2010 following the merger between the HRC and CCD images. From these mappings, and through multi-criteria analysis, map of susceptibility to erosion was made, which supported the environmental assessment of the studied area, indicating susceptible and unsuitable areas for the deployment of economic activities and urban sprawl. This study serves as a model can be replicated in other watersheds, assisting in the proper use planning and land use, aiming at the rational use of natural resources

Análise da dinâmica do uso da terra e sua interferência em enchentes na área urbana do município de Americana (SP)

Due to an intense process of population growth and urban density in Americana (SP), mainly due to the development of the local textile industry after 1970, there was, concomitant to the occupation of the margin of rivers and streams, soil sealing that increased the level of superficial runoff, triggering frequent floods. Based on the analysis of these processes we investigate the conditions of one densely urbanized area of the county, the Córrego do Parque, in three time series, 1977, 1996 and 2008. Taking as the starting the characterization and spatial distribution of landscape physiography, we prepared thematic letters and synthetic maps digital scale 1:10,000 from photointerpretation of aeroframes. The thematic maps were produced by scanning with subsequent edition using the software Auto-Cad Map. Checking the data and of geographic coordinates with GPS (Global Positioning System). Regarding land use classes, we used the description of the Soil Conservation Service (1975) which allowed us to get the Curve Number parameter, which will be used in hydrologic modeling for verification of flooding (Tucci, 1989). For the process of hydrologic modeling, we used models based on Methodology Object Oriented Modeling Applied to Water Resource Systems, Viegas Filho (1999), using the computer program called IPHS1, which uses models of the Soil Conservation Service (SCS , 2004), for conversion of rainfall-runoff and the spread of excessive rain. The results indicate that increased waterproofing generated by the change in use and occupation over the past decades promoted the increased surface runoff and drainage system overload, increasing the intensity of floods

Um olhar sobre a toponímia dos rios em Mato Grosso do Sul

This study aims to analyze designative hydronyms – terms that name watercourses in general – within the hydronymy of Mato Grosso do Sul, available in the toponymic Atlas of the State of Mato Grosso do Sul database – ATEMS, which were extracted from the official maps of the IBGE, scale 1:100,000, related to the 78 cities in the state. Among these hydronyms, 149 toponyms relating to rivers were selected and analyzed according to their etymology, the taxonomic classification and morphosyntactic structure.

Análise da suscetibilidade a corridas de massa aplicada a dutovias: estudo de caso na bacia do Ribeirão do Roque

This scientific research aimed at to analyse the susceptibility to debris flow of the watershed of Ribeirão do Roque (SP), focusing on the upstream areas of OSBRA pipeline. This is because, mass flow can cause damage to pipes, mainly due to conditioning hydro erosion of the land in the drainage crossings, including the undermining the banks of streams. Firstly, It was conducted a literature review, aiming to identify and understand the principal characteristics and conditions of debris flow. Secondly, the physical and anthropic factors and their respective weights of influence were selected and used to determine the mass flow susceptibility. It was selected the following physical factors: type and thickness of rocks, soil and unconsolidated materials; textural density; amplitude relief; relief slope; shaped valley; and shape of slopes. Such factors are present in the physiographic subdivision map of the study area. In addition, the anthropic attributes correspond to the classes contained in the land use map. Therefore, the physical and anthropic factors were integrated through the multi-criteria analysis in a GIS environment, generating a total susceptibility map of debris flow on the scale 1:50,000. The results showed that a significative part of the study area was classified as average susceptibility. However, it was identified areas with high susceptibility in the region in which the pipe cross the Ribeirão do Roque. Moreover, at which point the river presents a closed valley and a meander shape, without a fluvial plain that would be useful to attenuate the development of the process. Consequently, if a mass flow begins in any of these most susceptible regions located upstream of the pipe, the chances that the process develops by the river and causes the excavations of his bed are quite large. However, the pipelines cross these critical areas directly on the rock (diabase), which provides additional protection against possible ...

Comparação entre as análises paramétrica e integrada na suscetibilidade a escorregamentos no entorno de dutos: Duto Orbel, Rio de Janeiro

Pós-graduação em Geociências e Meio Ambiente - IGCE

Mapeamento geológico-geotécnico pelo método de detalhamento progressivo: aplicação no planejamento e gestão de obras rodoviárias

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Potencial de ocorrência de avarias ambientais em bacias hidrográficas com ocupação rural mediante análise morfométrica

The understanding of the geo-morphological characteristics allows the identification of flood areas and instability slopes among others important features for land use planning. The study of the hydrological net and the analysis of morphometric parameters help in the geomorphologic characterization, providing specific physics indicators that quantify the risks for environmental damages. The present work used Geographic Information Systems (GIS) and carried out the morphometric analysis of two watersheds in the Alto Rio Sorocaba, municipality of Ibiuna (SP). Using digitalized topographic bases in the scale 1:50,000, the main morphometric parameters were extracted and the Digital Elevation Model (DEM) was obtained. Hence the slope, ground illumination, hill orientation and relief feature maps were elaborated. The characteristics for the two watersheds were quite similar, both have low risks for floods and landslides. Therefore, the concave feature is the predominant hill shape for both watersheds. The morphometric parameters directly related to the river density of the watersheds showed some differences, because the Sorocabuçú watershed presents higher value, resulting in a higher level of relief development. Thus, with this characterization it is possible to provide subsidies for environmental planning actions to the area.

Análise de uso da terra e sua interferência em enchentes na região do Córrego Lavapés, Rio Claro (SP)

The development of cities is initially nearby rivers and with the intensification of the urbanization process occurs the soil sealing, leading to an increased level of water runoff, and, consequently, in a greater number of floods. The main goal of this study is to verify the interference of land occupation in the floods of the Lavapés Stream basin, Rio Claro (SP), in five temporal series, 1962, 1972, 1988, 1995 and 2014. The characterizations of land use were made from photo-interpretation and, thus, were produced thematic maps on scale 1: 20.000. The description of the Soil Conservation Service, 2007 was the basis for the classification of land use, thus achieving the CN parameter (Curve Number) used in hydrologic modeling done in IPHS1 program. The results indicate that soil sealing associated with the growth of the city of Rio Claro are responsible for increasing of the discharge in the Lavapés Stream basin and floods in this watershed