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Dinâmica morfossedimentar de praias dominadas por sistemas de arriba : (Peniche - Cascais)

Trindade, Jorge Manuel do Rosário
Fonte: Universidade Aberta de Portugal Publicador: Universidade Aberta de Portugal
Tipo: Tese de Doutorado
Publicado em //2010 POR
Relevância na Pesquisa
36.66%
Tese de Doutoramento em Geografia na especialialidade de Geografia Física apresentada à Universidade Aberta; A presente tese tem como objectivos principais a caracterização da morfodinâmica de praias e a determinação de áreas susceptíveis à erosão e à inundação marinhas em sistemas litorais arenosos da Estremadura, entre Peniche e Cascais. As praias estudadas são o sistema compósito praia-duna/praia-arriba da praia de Sta. Rita, o sistema praia-duna da praia Azul e o sistema praia-duna da praia da Foz do Lizandro. Pretende-se estudar a dinâmica planimétrica e das propriedades geométricas e volumétricas dos perfis de praia face à actuação dos vários agentes envolvidos nas modificações morfológicas, determinando os seus limites de variação e prevendo do seu comportamento morfodinâmico sob condições distintas das que ocorreram durante o estudo. Tendo em conta os resultados obtidos, avalia-se a susceptibilidade dos sistemas de praia à inundação e à erosão através do estudo dos factores associados à perigosidade e à modelação empírica de perfis de praia. O estudo baseia-se na aquisição sistemática de dados morfológicos através da realização de perfis transversais na praia emersa, utilizando técnicas topográficas localmente validadas. A par dos dados morfológicos são recolhidas amostras sedimentares dos elementos mais dinâmicos do perfil de praia para caracterização sedimentológica. A monitorização das praias forma a base...

Beachface and berm morphodynamics on a steep beach: Melides beach, Southwest Portugal.

Gama, Cristina; Baptista, Paulo; Marques da Silva, Rafael; Pinheiro, Isabel
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Aula
ENG
Relevância na Pesquisa
36.4%
The Melides beach, a sector of the Tróia-Sines Embayed Coast with 2.5km long, corresponds to a steep beach exposed to high-wave energy, with rapid erosion and accretion cycles related to winter storm incidence. The alongshore and cross-shore beach volume and width variability of the Melides beach were studied in detail using a survey methodology based on DGPS (Global Positioning System in Differential mode) and a Geographical Information System application. This survey methodology is based on a network of longitudinal and transversal DGPS profiles established on all subaerial beach. The three-dimension approach provided by DGPS methodology allowed a more robust description of the mean subaerial beach profile variations than bi-dimension studies provided by classical geodetic studies. The high match between alongshore patterns of the profile volumes variability before and after storm incidence in the Melides beach, suggests that the main factor that controls beach morphodynamics is the cross-shore sediment transport The seasonal cycle of erosion and accretion of the Melides beach seems to be triggered by variations in the wave incident energy (storm events). The incidence of a storm on January of 2008 led to significant shoreline shift with beachface retreat (24m) as well as...

Short-term evolution of a reflective beach sector in front of a coastal lagoon (Southwest).Portuguese coast)

Gama, Cristina; Albardeiro, Luís; Jacob, José; Pinheiro, Isabel
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Aula
ENG
Relevância na Pesquisa
36.53%
The subaerial beache act as detritical barriers in the opening and closing of lagoons located in sandy coastal ares. The study of beach morphodynamics, considering the evolution of the beachface and the berm, in these cases is critical to coastal management. The studied area located in an embayed sandy coastline at the Portuguese Southwest Atlantic Coast, is a 308m long subaerial, coarse to very coarse, sandy beach adjacent to the Melides lagoon entrance. In order to characterize the morphodynamics of the study area under the effects of storms (pre and post-storm) and tides (spring and neap tides) during a period of one year (April 2010 to April 2011), 26 field surveys were conducted. A survey grid with an alongshore lenght of 308m and a widht of 14-40m defined between the lower limit of the beachface and the backshore limit (entrance of the coastal lagoon or frontal dune) was used. We performed 12 cross-shore profiles 40m apart from each other. The alongshore profiles describes the main topographic variations (e.g. top of the beachface, berms elevation, beach cusps definition). Horizontal and vertical positioning was provided by Real-Time Kinematics (RTK) GPS. The results obtained allowed to develop high resolution Digital Elevation Models (DEM) using the ArcGIS software. DEM models were use to describe beach morphologicnd changes. The nearshore wave characteristics were described by the SWAN wave model considering as boundary conditions the wave data recorded at the Sines wave rider buoy. The run-up levels were calculated using the wave parameters and the beachface slope (0.12 to 0.18). During the study period were documented two episodes of opening and closing of the Melides lagoon due to storms effect...

Short-term evolution of a reflective beach sector in front of a coastal lagoon (Southwest Portuguese coast)

Gama, Cristina; Albardeiro, Luís; Jacob, José; Pinheiro, Isabel
Fonte: 32nd International Geographical Congress Publicador: 32nd International Geographical Congress
Tipo: Aula
ENG
Relevância na Pesquisa
36.5%
Several coastal lagoon entrances are controlled by the contiguous subaerial beach that works as a detrital barrier. Hence the importance of characterizing the adjacent beach morphodynamics regarding the beachface and berm reconstruction for coastal management proposals. The studied area, a subaerial beach sector of 308 m, located in front of the Melides coastal lagoon, is placed in an embayed sandy coastline at the Portuguese Southwest Atlantic Coast. During one year (April 2010 to April 2011), 26 field surveys were conducted in order to describe the evolution of this subaerial beach sector. The periodicity of the campaigns was defined in order to characterize the effects of storms (pre and post-storm) and tides (spring and neap tides), on subaerial beach morphodynamics adjacent to the lagoon entrance. A survey grid with an alongshore length of 308m and a width defined between the lower limit of the beachface and the backshore limit (entrance of the coastal lagoon or frontal dune) was used. This grid considered 12 cross-shore profiles apart by 40 m. The alongshore profiles describes the main topographic variations (e.g. top of the beachface, berms elevation, beach cups definition). Horizontal and vertical positioning was provided by Real-Time Kinematic (RTK) GPS. The results allowed the construction of high resolution Digital Elevation Model (DEM) of the studied area. This data were used to describe in detail the beach morphologic changes using the ArcGIS software. The superficial beach sediments were also collected pointing to the predominance of coarse to very coarse sand. The nearshore wave characteristics was described by the SWAN wave model considering as boundary conditions wave data recorded at the Sines wave rider buoy. The run-up levels were calculated considering the wave parameters and the beachface slope (0.12 to 0.18...

Sedimentation processes and beach morphodynamics active at the Doce River mouth, Espírito Santo State, Brazil

Albino,Jacqueline; Suguio,Kenitiro
Fonte: Academia Brasileira de Ciências Publicador: Academia Brasileira de Ciências
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2010 EN
Relevância na Pesquisa
46.27%
The coastal sedimentation model in the Doce River mouth and surroundings extends beyond the hydraulic jetty effect created by its stream-flow. During flooding, marine sediments transported by longshore currents are retained on the updrift side, causing strandline progradation. As the longshore current direction varies, local depositional and erosional effects can be produced and identified laterally within beach profiles from north and south of the Doce River mouth area. Sedimentological studies carried out in this river, beach and adjacent inner continental shelf sands showed that, at present, the influence of Doce River sediments is restricted to the area surrounding its mouth. Meanwhile, beach morphodynamic stages and present-day coastal-plain processes of sedimentation are directly affected by the Doce River discharge as a natural continuation of the Quaternary geological evolution of the area.

Características morfodinâmicas da praia do Pântano do Sul, Ilha de Santa Catarina, Brasil.

Oliveira, Ulisses Rocha de; Barletta, Rodrigo do Carmo; Peixoto, Janice Rezende Vieira; Horn Filho, Norberto Olmiro
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
36.54%
Este trabalho apresenta os resultados da análise das características morfodinâmicas da Praia do Pântano do Sul, uma praia de enseada localizada na costa sul da Ilha de Santa Catarina. Para isto, foram monitorados três perfis praiais, localizados em diferentes setores da praia, durante um ano. Amostras de sedimento foram coletadas durante o monitoramento dos perfis na base da duna frontal, pós-praia e face praial. Amostras adicionais de sedimento foram coletadas na face da praia com intervalo de 200 m. A praia foi classificada utilizando parâmetros morfométricos e também um modelo sequencial de evolução morfológica. O setor nordeste da praia (perfil 1) é permanentemente abrigado da ação direta da energia das ondas. Neste setor, as ondas raramente ultrapassam 0,5 metros de altura e o estágio predominante é Intermediário Terraço de Baixa Mar (W = 1,44), tendo este setor sedimentos arenosos mais finos que o restante da praia. A energia de onda tende a aumentar progressivamente em direção aos outros setores da praia (perfis 2 e 3). Decorrente desta distribuição de energia, o diâmetro do grão aumenta em direção aos setores sul da praia. A morfologia da praia proporciona duas linhas de arrebentação de onda e feições rítmicas com cúspides praiais. Os valores de ômega nos setores central e sul(perfis 2 e 3) foram 2...

Heterogeneity and homogeneity of southern Brazilian beaches: a morphodynamic and statistical approach

Pereira, Pedro de Souza; Calliari, Lauro J??lio; Barletta, Rodrigo do Carmo
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.47%
The characterization and beach morphodynamic differentiation along 620 km of Rio Grande do Sul state (RS) coastline has been principally done using beach profiles and their resulting morphometric parameters from the early 1990s through the present. The objective of the present work is to make a regional characterization, grouping the beaches with similar morphodynamic behavior along the RS coastline using multivariate statistical tools. For such purpose, a database containing topographic profiles and environment characteristics of 32 sites along the state coastline was built. A clustering analysis followed by a multidimensional scaling (MDS) analysis and an analysis of similarities (ANOSIM) was performed. The clustering and MDS results suggest that the data could be merged into six groups, one with dissipative tendencies, another with intermediate to reflective tendencies and three groups with intermediate characteristics. Each group showed distinct morphodynamic characteristics. Such differences are shown by the ANOSIM to be statistically significant. The three intermediate groups were differentiated in terms of beach mobility and percentage of medium-size sand, with higher mobility related to higher amounts of medium-size sand. The use of multivariate statistical techniques allowed a good differentiation between the RS beaches. Based on the results...

Frequency beach profile monitoring: implications in beach safety at Cassino beach, southern Brazil

Pereira, Pedro de Souza; Calliari, Lauro Julio; L??lis, Renato Jos?? Furigo
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.5%
During the summer of 2002 and 2003, daily monitoring of beach profiles were conducted at Cassino Beach, a highly dissipative beach in southern Brazil in order to verify changes in the dynamic inner and outer bar systems which could provide additional information to beach safety programs. Distances and depths of the troughs from the water line oscillated between 55m and 0.89m respectively for the first trough, to 160m, and 1.78mfor the third trough.At low wave energy conditions, average migration rates of the first and second bar reached 4.8 m/day. The total number of accidents, in the summer 2002, were equally associated with both, dissipative and the intermediate morphodynamic states, however the accidents in the summer 2003 occurred only in the intermediate type. The presence of a deep trough imprint in the intermediate beach type, a higher hazardous morphology level. The 2003 campaign documented stable profiles, showing a low mobility and constant morphology with the same beach type, with a deep trough that reached the depth of 2.4m at a distance of 96m from the water line. It is believed that this low mobility was caused by the presence of mud bottoms at the nearshore zone.

Barracas de Praia, praia de barracas: configuração, tipo e usos na praia do futuro, Fortaleza CE; Beach Huts, Beach of Huts: Configuration, type and uses in Praia do Futuro, Fortaleza-CE

Donegan, Lucy
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Arquitetura e Urbanismo; Conforto no Ambiente Construído; Forma Urbana e Habitação Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Arquitetura e Urbanismo; Conforto no Ambiente Construído; Forma Urbana e Habitação
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
36.34%
The purpose of this dissertation is to analyse the importance of the huts of Praia do Futuro to their users and to the city of Fortaleza in Ceará through the comprehension of relations between morphological categories - in urban and edified contexts - of the establishments and their use patterns. This place is one of the main recreation and leisure areas of the city, formed by six kilometres of waterfront, corresponding to a differentiated area through the coast. This space has beach huts with varied profiles: while some more simple huts persist, great complexes are being developed, building even water parks on the beach area. This study analyses relations between:i) spatial configuration (in geometric and mainly topological terms) based on the Social Logic of Space; ii) edified typology (analysing capacity, landscap treatment and program of the huts); and iii) use and environmental perception of the beach by its frequenters. There are consistent relations between the type of hut and their localization in the urban grid, of which were identified groups with different patterns: segregated (north, central and south) and integrated (north: more integrated. and south: less integrated). Such relations also reflect, in varied patterns of use and environmental perception. In spite of their strong economy...

Caracterização da dinâmica ambiental da região costeira do município de Galinhos, litoral setentrional do Rio Grande do Norte

Lima, Zuleide Maria Carvalho
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Geodinâmica e Geofísica; Geodinâmica; Geofísica Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Geodinâmica e Geofísica; Geodinâmica; Geofísica
Tipo: Tese de Doutorado Formato: application/pdf
POR
Relevância na Pesquisa
46.43%
This doctorate thesis concerning on the Characterization of the Environmental Dynamics of the Coastal Area of the Municipal district of Galinhos, Septentrional Coast of Rio Grande do Norte State, is located in the influence area of the Guamaré Petroliferous Pole, having as general objective the understanding of the active coastal dynamics in the region of Galinhos, whose specific objectives were: To study the variation of the coast line in the decades of 1954, 1967,1988, 1996, 2000, from remote sensing products; To elucidate the hypothesis of the region of Galinhos to have been an old system of islands barriers, using as basic tool the penetration radar in the soil - GPR; To monitor and to characterize the coastal dynamics of the study area starting from monthly data of beach profiles, sedimentological analysis, hydrodynamic data and environmental characterization data; which were used to feed the database of the N-NE network of Environmental Monitoring of Areas under Influence of the Petroliferous Industry;(REDE05/FINEP/CNPq/CTPETRO/ PETROBRAS). This research is justified, of the environmental point of view, by involving the mangrove ecosystem considered one of the most delicated environments of the State. From the viewpoint of the petroleum exploration...

Dinâmica Costeira dos Campos petrolíferos Macau/Serra, litoral setentrional do Estado do Rio Grande do Norte

Chaves, Marcelo dos Santos
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Geodinâmica e Geofísica; Geodinâmica; Geofísica Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Geodinâmica e Geofísica; Geodinâmica; Geofísica
Tipo: Tese de Doutorado Formato: application/pdf
POR
Relevância na Pesquisa
46.29%
This thesis describes the general behavior of the northern shore of the State of Rio Grande do Norte relating beach profile morphology with hydrodynamic and sedimentological parameters. The Macau and Serra Oil Field are inserted on this area and are under accelerated coastal erosion. At these oil fields are installed oil wells from PETROBRAS, nowadays located directly in the shoreline, under constant attacks of coastal processes (e.g. waves, tides and currents), which promote an intense morphodynamic variability of this sandy coast. The area was monitored for 24 months in three different stations (P01, P02 and P03). The methodology applied involved current techniques of beach profiles, hydrodynamical processes, remote sensing and geophysics. A synthesis of results obtained through the use of different time scales (monthly, lunar cycle, seasonal, annual) from a coastal dynamics study is presented. The average wind direction corresponded to 77ºAz (NE). The steepness of the berm and of the shoreface, as well as coastal current direction, do not present major changes, with an average of 36º for the steepness of the berm, 15º for the shoreface and 15º for the coastal current direction. This data set allows us to infer that the months of larger coastal erosion were November/2000 and April/2001...

Equilibrium Beach profile measurement and sediment analysis : Mustang Island, Texas.

Knezek, Erick B.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xiv, 114 p.;28 cm.
EN_US
Relevância na Pesquisa
36.4%
CIVINS; This engineering report describes the measurement techniques and results of an equilibrium beach profile survey and sediment analysis. The main objective of the project was to obtain an accurate equilibrium beach profile at a location on Mustang Island, and to compare the actual profile to a predicted profile. The predicted profile is based on the median grain size diameter of sediment samples taken from the dune crest to approximately 4000 ft offshore. The survey was accomplished using an electronic total station with a standard surveying rod on land, and the underwater profile was measured with a sled towed behind a boat. A triple prism was attached to both the top of the rod and sled. The sled is an aluminum and steel structure equipped with two 12 ft long skids and a 36.5 ft mast. The predicted profiles are based on two methods. One method uses Dean's equation for equilibrium beach profiles, z = Ax 2/3 , where z is the water depth, A is the profile scale factor related to the sediment fall velocity, and x is the distance offshore. The other method involves a more complex analysis described by Dean and Dalrymple, which accounts for a variation in sediment size and profile scale factor, A, in the offshore direction. Both methods are described and compared in this report. This data will also be used by Dr. R. G. Dean of the University of Florida in a study he is conducting on equilibrium beach profile prediction; http://archive.org/details/equilibriumbeach00knez; CIVINS

Monitoramento da dinâmica costeira da praia de Ponta Negra

Chacon, Aline Freitas
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Geografia; Dinâmica e Reestruturação do Território Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Geografia; Dinâmica e Reestruturação do Território
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
46.56%
This dissertation includes the monitoring of coastal environmental dynamics at three points distinct from Ponta Negra beach, located on the South Coast of Natal, capital of Rio Grande do Norte, in the period June 2012 to May, 2013. For this, the following hypotheses were developed: Which actors morphodynamic and/or anthropogenic responsible for the changes in the study area? And yet, the configuration of the morphodynamic state of the beach, dissipative, reflective or intermediate? Faced with these questions , studies on the beach environment has its relevance as they may clarify the risks and responsibilities of anthropogenic intervention and also assist managers in more targeted action regarding the protection of praiais systems, since once committed, it is very difficult recover the environmental framework of the area, being greatly more feasible the development of multidisciplinary work plans that can guide human actions possible in search of an understanding to the harmonious interaction between society and the beach system. Its main goal is the understanding of the processes of coastal dynamics, methodological procedures that supported the implementation of this research were based on the object of study related literature associated with the collection of data resulting from beach profiles made monthly in spring tides (full moon)...

Morfodinâmica praial: uma breve revisão

Calliari, Lauro Julio; Muehe, Dieter; Hoefel, Fernanda Gemael; Toldo Junior, Elirio Ernestino
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
36.54%
Since the early 1930's, beach profiles have been broadly classified in one of the two types: storm profiles or swell profiles associated, respectively, with steep or low waves. Changes in beach profiles involves so many variables that becomes very difficult to obtain a model which can account for a sucessfull explanation or prediction of these changes. Only in the early 1970's. the sediment characteristics, the process of wave transformation in shallow waters and the coupling between the three-dimensional morphology and the hydrodynamics were sistematically analyzed in order to get a better understanding of the processes responsible for beach changes and its evolutionary sequences. In this paper a brief review about the sucessfull beach morphodynamic models developed by the Australian school of coastal geomorphology is presented as well as some results of this approach applied to some of the southern and southeastern Brazilian beaches.; Desde o início dos anos 30 perfis de praia foram classificados em um dos dois tipos: perfis de tempestade ou perfis de ondulação associados, respectivamente, com ondas de alta e baixa esbeltez. Mudanças no perfil praial envolvem muitas variáveis, tornando muito difícil a formulação de modelos de prediçâo de comportamento praial. Somente a partir da década de 70...

Cross-shore transport on gravel beaches

Hicks, Betsy
Fonte: University of Delaware Publicador: University of Delaware
Tipo: Tese de Doutorado
Relevância na Pesquisa
36.47%
Kobayashi, Nobuhisa; Puleo, Jacks A.; Coastal gravel can be found in both natural beach settings and in man-made protective structures like revetments. The experiment presented in this report was conducted in a wave flume to investigate the cross-shore evolution of gravel beaches under irregular laboratory wave conditions. A total of four tests were performed with varying initial beach profiles and incident significant wave heights. The first two tests were on an initially steep slope of 1/2 with two different significant wave heights, both of which created erosional conditions. The third test had an initially milder 1/5 slope resulting in beach accretion and the final test measured the onshore migration of a gravel bar. Each test consisted of either 18 or 36 wave bursts of 400 seconds, after which the profiles appeared to be quasi-equilibrium. Free surface and velocity data was collected and time-averaged for each 400 second wave burst and profile measurements were recorded for the initial, final and at least three intermediate profiles. The quasi-equilibrium profiles observed were similar in shape, but were affected by the differences in wave height and the initial profile conditions. Recorded hydrodynamic and profile evolution data was used for validation of a numerical model. The tests were designed to investigate the applicability of a numerical model developed for damage progression of stone armor layers to finer gravel material and to test the accuracy of the bed load formulation originally developed for a sand sediment transport model. The critical stability parameter used to determine movement for stone armors was found to predict profile change for the two erosion tests. The bed load formula required adjustment to better predict the amount and extent of onshore transport for the mild slope and bar migration test.; University of Delaware...

Morfodinâmica praial: uma breve revisão; Beach morphodynamics: a brief review

Calliari, Lauro Júlio; Muehc, Dieter; Hoefel, Fernanda Gemael; Toldo Jr., Elírio
Fonte: Universidade de São Paulo. Instituto Oceanográfico Publicador: Universidade de São Paulo. Instituto Oceanográfico
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 01/01/2003 POR
Relevância na Pesquisa
46.56%
Desde o início dos anos 30 perfis de praia foram classificados em um dos dois tipos: perfis de tempestade ou perfis de ondulação associados, respectivamente, com ondas de alta e baixa esbeltez. Mudanças no perfil praial envolvem muitas variáveis, tornando muito difícil a formulação de modelos de prediçâo de comportamento praial. Somente a partir da década de 70, as características dos sedimentos c os processos de transformação de ondas operantes na plataforma interna e antepraia, acoplados com a morfologia tridimensional e a hidrodinâmica da praia, começaram a ser estudados de maneira integrada. Tais estudos levaram a um melhor entendimento do comportamento de sistemas praiais e zonas de arrebentação e também à formulação de modelos seqüenciais de comportamento morfodinâmico daqueles sistemas. Apresenta-se aqui uma breve síntese dos principais trabalhos e modelos introduzidos pela escola australiana de geomorfologia costeira na área de morfodinâmica praial e o resultado de sua aplicação em algumas praias do sul e sudeste do Brasil.; Since the early 1930's, beach profiles have been broadly classified in one of the two types: storm profiles or swell profiles associated, respectively, with steep or low waves. Changes in beach profiles involves so many variables that becomes very difficult to obtain a model which can account for a sucessfull explanation or prediction of these changes. Only in the early 1970's. the sediment characteristics...

Caracterização morfodinâmica do litoral Norte Fluminense, RJ, Brasil; Coastal morphodynamics of the northern Rio de Janeiro State, Brazil

Bastos, Alex Cardoso; Silva, Cleverson Guizan
Fonte: Universidade de São Paulo. Instituto Oceanográfico Publicador: Universidade de São Paulo. Instituto Oceanográfico
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 01/01/2000 POR
Relevância na Pesquisa
36.4%
A morfologia das praias é reflexo da ação hidrodinfunica com o tipo de sedimento disponível. Esta int~ação se dá a partir da base de ação das ondas, tornando-se mais efetiva na zona de arrebentação onde a energia é dissipada, originando wna zona de surfe que se estende em direção à linha de costa até Q limite do espraiamento na face de praia. O objetivo deste trabalho é apresentar as características morfodinâmicas do litoral NE do Estado do Rio de Janeiro, baseando-se na análise da variação espaço Hemporal de perfis de praia, na morfologia da plataforma continental e em fotos aéreas. Os perfis de praia foram levantados durante cinco anos pela PETROBRÁS S/A, em oito estações ao longo do litoral. O comportamento morfodinâmico distinto de setores do litoral estudado é função do padrão de ondas e direção da linha de costa, morfolQgia da plataforma interna controlando a extensão da zona de surfe e o número de zonas de arrebentação, características dos sedimentos e gradiente da face de praia. Foram reconhecidos quatro compartimentos morfodinâmicos distintos, com base na morfologia dos perfis praiais e plataforma interna, no índice de mobilidade da linha de praia, granulometria x gradiente da face de praia e o parâmetro Q. Os quatro compartimentos são: Atafona/Foz do Rio Paraíba do Sul - estágio morfodinâmico intermediário a dissipativo...

INTERANNUAL MORPHOLOGICAL CHANGES OF BOA VIAGEM BEACH - NORTHEAST COAST OF BRAZIL; VARIABILIDADE MORFOLÓGICA INTERANUAL DA PRAIA DE BOA VIAGEM, LOCALIZADA NA REGIÃO NORDESTE DO BRASIL

Gregorio, Maria das Neves; UFPE; Araujo, Tereza C. Medeiros de; UFPE
Fonte: UFPR Publicador: UFPR
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 28/01/2010 POR
Relevância na Pesquisa
36.58%
Boa Viagem and Pina are urban beaches highly economically important both locally and regionally providing protection for the southern coast of Recife, Pernambuco – Brazil. The objective of this paper is to study the interannual morphological changes which occur on these beaches in order to gather information on the erosion processes. For this purpose 6 topographical profiles were monitored, monthly, from August 2002 to December 2005, during spring tide. To establish the position of each profile it was considered whether the beach was protected by reefs, or not, and if there were coastal protection structures. The largest morphological variation was observed in profiles located to the extreme South and North of the area of study (profiles 1 and 5), as well as the profiles located immediately to the North of the coastal protection features (profiles 4A and 4B). Profiles located in the middle of the study area showed stability. As for sedimentary budget the following variations were observed: negative sedimentary budget in profiles P1 (-4.0 m3/m), P4A (-22.0 m3/m), P4B (-7.0 m3/m) and P5 (-1.0 m3/m); positive sedimentary budget in profiles P2 (+2.0 m3/m) and P3 (+4.0 m3/m). Profiles 2 and 3 presented a more consistent budget than those of the profiles located at the extremities of the area (profiles 1...

A preliminary analysis of flat-gravel transport over a Sandy Beach, Pehuén Co, Argentina

Perillo,Gerardo M.E.; Perillo,Mauricio M.; Piccolo,M. Cintia; Revollo Sarmiento,G. Noelia; Revollo Sarmiento,Natalia V.; Alberdi,Ernesto D.
Fonte: Latin American journal of sedimentology and basin analysis Publicador: Latin American journal of sedimentology and basin analysis
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2011 EN
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46.27%
Pehuén Co Beach, on the southwest coast of the Buenos Aires Province (Argentina), provides an example of an heterogeneous (mixed sand-gravel) sediment beach with gravels of the most diverse size and origin. Over 40% of the pebbles are carbonate flat gravels. Field observations included beach profiles, measurements of wave generated currents with an acoustic currentmeter (ADV), videos of 5 x 5 m grid located on the swash zone during inundation from a nearby tower. Video films where rectified and analyzed using PIV and wavelets. Based on the results, we demonstrated that flat gravels can be easily transported upbeach distances in excess of 5 m in about 1.5 h. This period corresponds to the high tide situation and covering the steepest beachface segment. Wave conditions during the experiment corresponded to low breaker height and short periods, but by no means they could be considered as storm waves demonstrating that gravels can be transported even by saltation during fair weather conditions.

Inundation and erosion susceptibility in wave dominated beaches

Trindade,Jorge; Ramos-Pereira,Ana
Fonte: Centro de Estudos Geográficos Publicador: Centro de Estudos Geográficos
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2013 EN
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36.37%
Hydrodynamic forces over the beach sediments are the main driving factors affecting the frequency and magnitude of morphological changes in beach systems. Most of the time, these driving factors act in a foreseeable way and do not represent any danger either to the coastal systems or to their population. However, hydrodynamic forces are also capable of inducing high morphodynamic behaviour on the beach profiles and very often in a short period of time; this endangers people and property and leads to system retreat. The most common consequences of the occurrence of this type of phenomena over the landforms are costal inundation and erosion. Still, many coastal systems, especially beach systems, have recovery mechanisms. Resilience levels have a very important role in the beach morphodynamic status and exposure to potential damaging event assessments. The Portuguese West coast has a high wave energetic environment during winter, where waves with 5 year recurrence period can reach 9.2m and storms are frequent. This research aims to access beach hazard and susceptibility to inundation and erosion. Three beach systems were selected and monitored applying sequential profiling methodology over a four year period (2004-2007). Sta. Rita, Azul and Foz do Lizandro beaches are representative systems of the coastal stretch between Peniche and Cascais...