Concrete bridge decks in Utah are experiencing observable deterioration due primarily to freeze-thaw cycles and the routine application of deicing salts during winter maintenance activities. Given the need for increasingly cost-effective strategies for bridge deck maintenance, rehabilitation, and replacement (MR&R), the Utah Department of Transportation (UDOT) initiated this research to ultimately develop a protocol offering guidance as to whether deteriorated bridge decks should be rehabilitated or replaced. While threshold values for various non-destructive condition assessment methods were proposed in earlier UDOT research, this work focused on implementing the recommended test criteria. Twelve bridges were identified by UDOT engineers for inclusion in the study, and data were collected from each deck to determine whether the bridge decks warranted rehabilitation or replacement based on the proposed threshold values. Several evaluation techniques were employed to assess concrete bridge deck condition, including visual inspection, hammer sounding and chaining, dielectric measurements, ground-penetrating radar imaging, resistivity testing, half-cell potential testing, and chloride concentration testing. The condition assessment testing confirmed that chloride-induced corrosion of reinforcing steel is the primary mechanism of deck deterioration and that inadequate cover over the upper steel mat facilitated accelerated corrosion damage in many instances. The bridge deck condition analyses produced from the results of non-destructive testing were compared to the visual inspection ratings assigned to each deck by UDOT. Concrete bridge deck condition data should be collected regularly through inspection and monitoring programs to facilitate prioritization of MR&R strategies for individual bridges and to evaluate the impact of such strategies on the overall condition of the network. Performance indices based on selected condition assessment parameters should be developed for use in bridge management activities, and mathematical deterioration models should be calibrated in order to forecast both network-level and project-level conditions and predict funding requirements for various possible MR&R strategies. Further research, including statistical analyses of the data presented in this report, should be completed to develop relevant mathematical deterioration models for predicting the service lives of concrete bridge decks in Utah.

[pt] Este trabalho apresenta a análise das características de dispersão temporal do canal de propagação banda ultra larga (UWB) feitas a partir da técnica de sondagem em freqüência na banda de 850MHz em sete diferentes ambientes Indoor. Nestes ambientes os parâmetros de dispersão temporal dados pelo retardo médio, retardo RMS e banda de coerência são obtidos. Uma análise adicional sobre a perda de propagação e sobre a robustez do sinal UWB a desvanecimento de pequena escala é também realizada. / [en] This work presents an analysis of the ultra wideband (UWB) channel temporal dispersion characteristics evaluated from the frequency sounding technique over a bandwidth of 850MHz at seven different indoor environment. In each environment, the channel temporal dispersions parameters were assessed in terms of mean delay, delay spread and coherence bandwidth. An additional analysis related to path loss and UWB robustness was also evaluated.

Due to the advancement in technology and the increase in the amount of data beingtransferred through wireless channels, many developments in the techniques and speedof data transfer have been observed in the past few decades. The current trend incellular technology is transforming from 4G to 5G. So, to meet future requirements,it is highly necessary to have further improvements in technology like modulationtechniques, Channel access methods, etc. Many top research institutes around the worldare investing heavily in research and development of 5G.Radio waves have been used for a very long time in mobile phone communication,but providers are experimenting with broadcasting on millimeter waves which usehigher frequencies ranging from 6GHz to 300GHz. Data characteristics like power,SNR, interference, etc. need to be evaluated for these high frequencies. As 5G is still ininitial phases of development, there are not many testing tools to check and evaluateits performance. A testbed is a testing tool which is used for conducting rigorous,transparent, and replicable testing, experimenting and evaluating the performance ofthese propagated data at these high frequencies.The thesis work evaluates the implementation structures of the 5G testbed @15GHzand its performance in indoor and outdoor scenarios. It also talks about the methods ofsignal generation through Matlab and it’s transmission at 15GHz using Xilinx FPGAand Analog devices’ FMCOMMS5 transceiver. This data is then transmitted andreceived by patch antennas provided by Ericsson AB. Various techniques were used inorder to improve the signal, like using RF hardware components and software modules.Different channel sounding techniques were used in order to achieve the synchronizationbetween the transmitter and the receiver node in order to measure the properties ofthe channel. All of the experiments were performed by implementing a single-inputsingle-output system (SISO) module of the 5G testbed. This SISO system can be easilytransformed into a multiple-input-multiple-output system (MIMO) by replicating theoriginal SISO system.The result shares some interesting findings on the readiness of the 5G testbed for aiiiivbetter understanding of the future technology. It is concluded that this testbed providessomewhat a reliable platform to test the performance of the 5G technology. / Tack vare teknikutveckling och ökning i mängden data som sänds trådlöst, hardatatakterna ökat enormt under de senaste decennierna. Den senaste trended inomtrådlös kommunikationärövergången från 4G till 5G. För att möte framtida krav,finns det därför behov av ytterligare teknologiutveckling, t ex i modulationstekniker och kanalaccessmetoder. Många forskningsinstitut runt om i världen investerar därför i forskning och utveckling av 5G.Radiovågor har använts under väldigt lång tid för mobil kommunikation, men tillverkare och operatörer experimenterar med sändningar i millimetervågsområdet, som använder högre frekvenser i området från 6GHz till 300GHz. Egenskaper såsom effektdämpning, SNR, interferens, osv, behöver utvärderas för dessa högre frekvenser. Eftersom utvecklingen av 5G fortfarande är i en tidig fas, finns inte så många testverktygtillgängliga för prestandautvärdering. En testbädd är ett testverktyg som användsför att utföra rigorös, transparent och upprepningsbar testning, experimentering och prestandautvärdering av data som har sänts vid dessa höga frekvenser.Denna rapport utvärderar implementationsstrukturer för en 5G-testbädd vid 15GHz,och dess prestanda i inomoch utomhusscenarier. Den beskriver även metoder försignalgenerering via Matlab och sändning vid 15GHz mha Xilinx FPGA och Analog devices’ FMCOMMS5 radiomoduler. Signalen sänds sedan via patch-antenner från Ericsson AB. Olika metoder användes för att förbättra signalen, både med radiofrekvens hårdvara och mjukvarumoduler. Olika kanalmätningsmetoder har använts för att nå synkronisering mellan sändaroch mottagarnoderna, för att mäta kanalegenskaper. Alla experimenten utfördes genom att implementera en SISO-modul (en sändarresp. mottagarantenn) av 5G-testbädden. Detta SISO-system kan enkelt utökas till ett MIMO system (flera sändaroch mottagarantenner) genom att replikera SISO-systemet.Resultaten visar att 5G-testbädden är redo att användas för att nå bättre förståelse av framtida teknologin. Slutsatsen är att testbädden erbjuder en tämligen påliglig plattformför att utvärdera prestanda för 5G-teknologi.

Acoustic survey techniques are widely used to quantify abundance and distribution of a variety of pelagic fish such as herring (Clupea harengus). The information provided is becoming increasingly important for stock assessment and ecosystem studies, however, the data collected are used as relative indices rather than absolute measures, due to the uncertainty of target strength (TS) estimates. A fish’s TS is a measure of its capacity to reflect sound and, therefore, the TS value will directly influence the estimate of abundance from an acoustic survey. The TS is a stochastic variable, dependent on a range of factors such as fish size, orientation, shape, physiology, and acoustic frequency. However, estimates of mean TS, used to convert echo energy data from acoustic surveys into numbers of fish, are conveniently derived from a single metric - the fish length (L). The TS used for herring is based on TS-L relationships derived from a variety of experiments on dead and caged fish, conducted 25-30 years ago. Recently, theoretical models for fish backscatter have been proposed to provide an alternative basis for exploring fish TS. Another problem encountered during acoustic surveys is the identification of insonified organisms. Trawl samples are commonly collected for identification purposes, however, there are several selectivity issues associated with this method that may translate directly into biased acoustic abundance estimates. The use of different acoustic frequencies has been recognised as a useful tool to distinguish between different species, based on their sound reflection properties at low and high frequencies. In this study I developed theoretical models to describe the backscatter of herring at multiple frequencies. Data collected at four frequencies (18, 38, 120 and 200 kHz) during standard acoustic surveys for herring in the North Sea were examined and compared to model results. Multifrequency backscattering characteristics of herring were described and compared to those of Norway pout, a species also present in the survey area. Species discrimination was attempted based on differences in backscatter at the different frequencies. I examined swimbladder morphology data of Baltic and Atlantic herring and sprat from the Baltic Sea. Based on these data, I modelled the acoustic backscatter of both herring stocks and attempted to explain differences previously observed in empirical data. I investigated the change in swimbladder shape of herring, when exposed to increased water pressures at deeper depths, by producing true shapes of swimbladders from MRI scans of herring under pressure. The swimbladder morphology representations in 3-D were used to model the acoustic backscatter at a range of frequencies and water pressures. I developed a probabilistic TS model of herring in a Bayesian framework to account for uncertainty associated with TS. Most likely distributions of model parameters were determined by fitting the model to in situ data. The resulting probabilistic TS was used to produce distributions of absolute abundance and biomass estimates, which were compared to official results from ICES North Sea herring stock assessment. Modelled backscatter levels of herring from the Baltic Sea were on average 2.3 dB higher than those from herring living in northeast Atlantic waters. This was attributed to differences in swimbladder sizes between the two herring stocks due to the lower salinity Baltic Sea compared to Atlantic waters. Swimbladders of Baltic herring need to be bigger to achieve a certain degree of buoyancy. Morphological swimbladder dimensions of Baltic herring and sprat were found to be different. Herring had a significantly larger swimbladder height at a given length compared to sprat, resulting in a modelled TS that was on average 1.2 dB stronger. Water depth, and therefore the increase in ambient pressure, was found to have a considerable effect on the size and shape of the herring swimbladder. Modelled TS values were found to be around 3 dB weaker at a depth of 50 m compared to surface waters. At 200 m, this difference was estimated to be about 5 dB. The Bayesian model predicted mean abundances and biomass were 23 and 55% higher, respectively, than the ICES estimates. The discrepancy was linked to the depth-dependency of the TS model and the particular size-dependent bathymetric distribution of herring in the survey area.

As the biomass of jellyfish (medusae of the Scyphozoa and Hydrozoa) has risen in numerous locations worldwide, awareness of their potential to exert a controlling influence on marine ecosystems and hinder the recruitment of fish stocks has increased. Medusae are capable of intensive, size–selective, predation on zooplankton, which may alter the composition of the plankton community. Jellyfish are often found in dense layers, up to hundreds of metres thick, which can extend horizontally for hundreds of kilometres. Such aggregations may benefit specialist feeders, such as turtles, that rely upon jellyfish for food and those fish that are able to find refuge under the jellyfish umbrellas. Nonetheless, the predominance of jellyfish in pelagic ecosystems is not generally viewed as desirable; in fact, this situation has been portrayed as the result of pollution and overexploitation of otherwise productive seas. However, jellyfish are sensitive indicators of environmental change, and their populations appear to respond to climatic fluctuations, so jellyfish warrant study for their intrinsic ecosystem role particularly given present concerns over climate change. With growing acceptance that fishery management should take an holistic ‘ecosystem approach’, knowledge of the interactions between jellyfish, fisheries and climate may be vital in progression towards the goal of ecosystem–based sustainable management of fisheries. Unfortunately, due to their gelatinous nature, medusae are difficult to sample using conventional netting techniques and data on changes in distribution and abundance are consequently sparse. Recent studies have demonstrated that medusae can be detected acoustically and that this technique could provide a rapid and cost–effective estimate of their biomass and distribution. This thesis reports my endeavour to demonstrate the ecosystem role of medusae and to develop acoustic techniques to monitor their biomass. Through regession analyses, I link the abundance of medusae (Aurelia aurita, Cyanea lamarckii, and Cyanea capillata) in regions of the North Sea to climatic fluctuations, as quantified by the North Atlantic Oscillation Index, and show that medusae may be important indicators of regional ecosystem change. The mechanisms linking climatic fluctuations to ecosystem changes are explored via a correlative modelling approach using General Additive Models; I show that the mechanisms are location dependent and explainable in terms of direct, rapidly responding (intra–annual) influences (surface warming, river run–off, and wind–driven mixing and advection) and longer–term (interannual) oceanographic responses (changes in circulation currents i.e. the northward extent of the gulf stream and relative strength of inflow into the North Sea of the North Atlantic current, Continental Shelf Jet and Arctic waters). I present correlative evidence for a detrimental impact by Aurelia aurita on herring 0–group recruitment, once the influence of interannual change in herring spewing stock biomass on recruitment is factored out through modelling with a Ricker stock–recruitment relationship. Similarly, a commensal relationship between whiting and Cyanea spp. medusae is shown to improve North Sea whiting survival to the 1–group. In progress towards the automated acoustic identification of species, I have developed an in situ discrimination tool that can distinguish between echoes from: Aequorea aequorea; Chrysaora hysoscella; clupeid fish (sardine, anchovy and round herring); and horse mackerel/Cape hake. The technique relies upon characteristic differences in echo strength between frequencies, which are determined for each jellyfish species and finfish group using combined multifrequency acoustic and pelagic trawl samples. This method has facilitated the world’s first acoustic–based estimate of jellyfish biomass in the Namibian Benguela Sea. The 12.2 million tonnes of biomass of medusae (Aequorea aequorea and Chrysaora hysoscella) in the Namibian Benguela Sea was found to be greater than the combined biomass, 3.6 million tonnes, of commercially important fish (horse mackerel, Cape hake, sardines, anchovy, and round herring) in the same area. These results suggest that medusae may have an important role in the Benguela ecosystem that has previously been overlooked and that their biomass should be monitored.

Approved for public release, distribution is unlimited / This thesis study focuses on understanding the dissipation processes of the stratocumulus deck after sunrise. This objective is met through careful analyses of observational data as well as model simulations. Measurements from the Marine Atmosphere Measurement Lab (MAML) of the Naval Postgraduate School (NPS) are used in this study. In particular, the half-hourly wind profiler/Radio Acoustic Sounding System (RASS) measurements were used to determine the boundary layer top and the evolution of the boundary layer mean thermodynamic properties during the cloud breakup period. Measurements from a laser ceilometer and the routine surface measurements are also used to detect the variation of cloud base height, the evolution of the cloud deck, and the onset of sea breeze. These measurements revealed the increase of the boundary layer depth after sunrise followed by a decrease of the boundary layer depth after the onset of the sea breeze, which points to the role of surface heating and sea breeze development in modulating cloud evolution. The effects of surface heating and sea breeze are further tested using a 1-dimensional mixed layer model modified for coastal land surfaces. / Lieutenant Commander, United States Navy

L’étude des structures raidies est un sujet de recherche récurrent. En effet, celles-ci sont présentes dans de nombreuses applications industrielles. Leur utilisation offre de nombreux avantages notamment du point de vue de l’allègement, critère qui est particulièrement important dans l’industrie automobile par exemple. Dans un tout autre domaine, la table d’harmonie de piano constitue un exemple typique de ces structures raidies et les problèmes relevés par les professionnels du domaine sont nombreux. Aujourd’hui, les ressources numériques permettent de prendre en compte de nombreux phénomènes dans les modèles développés avec pour conséquence, une difficulté d’interprétation entre les données d’entrée et de sortie. En considérant moins de paramètres à la fois, les modèles simplifiés présentent alors l’avantage de pouvoir en séparer la participation dans le rendu global. En prenant comme point de départ une plaque simplement supportée rectangulaire orthotrope dite « spéciale » dans laquelle la table est inscrite, la forme de la table d’harmonie est recréée par ajout d’une densité de ressorts ponctuels dans le domaine complémentaire. Par couplage avec des superstructures collées sur chaque face, il est possible de déterminer le comportement vibratoire de l’instrument ainsi que le rayonnement acoustique à partir des impédances de rayonnement d’une plaque simplement supportée bafflée. Ce modèle analytique est par la suite couplé à une corde et résolu dans le domaine temporel et présente alors l’avantage de pouvoir évaluer perceptivement l’impact de modifications structurelles. L’originalité d’un tel calcul tient dans le fait que des forces d’interactions assurent la continuité entre les soussystèmes et deviennent des inconnues du problème, comme dans les problèmes de contacts ou de frottements. Enfin, la prise en compte des petites non-linéarités géométriques de la corde sera faite en les considérant comme des seconds membres des équations du mouvement, ce qui permet de conserver la notion de modeslinéaires / Ribbed structures are a current subject of study and they are often used in many industrial domain. Indeed, there use offers some advantages as for example in automotive domain to reduce the weight of vehicule that is an important actual constrain. In the musical domain ribbed structures are also often used and musical instruments mixed structural, perceptive and subjective considerations. In that domain, one of the main difficulties is to translate the language between the science and the music and to make equivalence between phenomena describe by the musicians and scientific indicators. The piano soundboard is a typical example of these ribbed structures and difficulties reported by piano makers are many. Nowadays, numerical computing resources allow to take into account some phenomena in modeling but as a consequence, it appears a “black box effect” between input and output data. Taking into account less parameters, reduced models offer the advantage to separate the influence of each parameter in the final result. Taking into account as starting point a simply supported rectangular plate with special orthotropy, the edges of the soundboard are described by an addition of punctual springs in the fictive domain. Coupling to it some stiffeners on the both faces, it is possible to calculate the vibratory behavior of the instrument such as the acoustic radiation through the acoustical radiation impedances of the baffled simply supported plate. This simplified analytical modeling is representative of phenomena found in the literature and is also well adapted to parametrical studies. So, it highlights the space localizations of vibration, due to the conception of the instrument, and allows studying the influence of structural parameters on the mobility along the bridge, the acoustical radiated power for example. In order to qualify, with a reduced computing cost, the influence of structural parameters on the perceived sound, this analytical model for ribbed structure is coupled to a string and solved in time domain.

A caracterização geológica e geotécnica dos locais de implantação de aterros sanitários é fundamental, tanto para fornecer subsídios adequados ao projeto de instalação das células de deposição dos resíduos sólidos urbanos (RSU), quanto para que se conheçam as características da área antes de ser modificada pela obra. Neste sentido, o presente trabalho visou mostrar a contribuição que a geofísica, com o uso da técnica da eletrorresistividade e do potencial espontâneo, associado a informações de investigação geotécnica direta pode dar para o estabelecimento de um background da área de instalação do aterro sanitário da cidade de São Carlos-SP. Foram realizados 7 caminhamentos elétricos (CE) com o arranjo dipolo-dipolo com eletrodos espaçados de 10 metros e três sondagens elétricas verticais (SEV), utilizando o arranjo Schlumberger, com profundidade de investigação de até 100 metros. Para processamento dos modelos bidimensionais dos CE utilizou-se o programa RES2DINV, e enquanto que para as SEV foi utilizado o modelo unidimensional. A interpretação dos modelos geoelétricos foi aperfeiçoada pela confrontação com informações geológico-geotécnicas prévias da área, obtidas nos estudos de impacto ambiental (EIA/RIMA) e resultados de sondagens de simples reconhecimento (SPT), realizadas na fase de estudo para implantação do aterro sanitário. Com isso foi possível definir com clareza a profundidade do topo rochoso e das zonas de maior umidade nos CE e SEV. O conjunto de seções de CE foi georeferenciada com o auxílio de GPS de precisão, o que permitiu o tratamento espacial das informações e o estabelecimento dos mapas da superfície do topo rochoso, das zonas de fluxo de água subterrânea e da espessura dos materiais inconsolidados. O conjunto de informações obtido permitiu identificar locais possíveis para a instalação futura de poços de monitoramento, assim como os dados geoelétricos das várias camadas servirá como padrão para identificar eventuais contaminações do solo ou da água subterrânea no futuro. A identificação da presença do topo rochoso em pequena profundidade, em algumas áreas do aterro, permite o melhor planejamento das escavações para instalação das células de deposição do RSU. / The geological and geotechnical characterization of landfill implantation areas is crucial; even to provide appropriate subsidies of urban solid residues (USR) installation project of deposition cells and for knowing the characteristics of the area before being modified by the work. In this sense, the present work aimed to show the contribution that the geophysics, with the use of electrical resistivity technique and the spontaneous potential, associated with direct geotechnical investigation information can give to the establishment of a background of landfill installation area from São Carlos-SP city. Were performed 7 electrical imaging (EI) with the dipole-dipole array with electrodes spaced by 10 meters and three vertical electrical sounding (VES), using the Schlumberger array with depth research up to 100 meters. For processing of two-dimensional models of the EI was used the RES2DINV program and while for the vertical electrical sounding (VES)-was used one-dimensional model. Interpretation of geoelectric models was enhanced by the confrontation with geological and geotechnical information of prior area, obtained in the environmental impact assessment (EIA) and results of a simple reconnaissance probes, performed in the study phase for the landfill implementation. It was possible to clearly define the depth of the bedrock and the higher humidity areas in the EI and VES. The set of sections electrical Imaging (EI) was georeferenced with the aid of GPS accuracy that allowed the spatial treatment of Information and the setting maps of the bedrock surface, the groundwater flow zones and the thickness of the unconsolidated materials. The obtained set of information enabling identification of possible locations for the wells future monitoring installation, as well as the geoelectrical data from several layers will be use as a standard to identify possible contamination of the soil or groundwater in the future. The identification of bedrock presence in small depth, in some areas of landfill, allows better planning of excavation for installation of MSW deposition cells.

A variabilidade das propriedades físicas do solo apresenta impacto sobre o desempenho das atividades de produção agrícola. Métodos indiretos para obtenção de informações sobre as propriedades do solo com interesse agronômico são utilizados com o intuito de favorecer o uso de insumos de modo mais adequado. A condutividade elétrica aparente do solo (CEa) é influenciada por diversas propriedades, muitas delas interrelacionadas e com variabilidade em curta distância, sendo difícil a separação dos diversos fatores. As medidas de CEa são usualmente tomadas em superfície com arranjos de eletrodos para prospecção de um volume de solo proporcional à distância entre eles. Neste trabalho foi utilizada uma metodologia que permitiu identificar algumas das propriedades com maior impacto sobre a CEa, merecendo destaque aquelas relacionadas ao espaço poroso do solo. A caracterização detalhada da variação da CEa ao longo do perfil do solo e sua comparação com aquela obtida a partir da sondagem elétrica vertical permitiram identificar algumas limitações desta técnica. A presença de camadas com variação de diversas propriedades físicas e de umidade no perfil do solo alterou os valores observados em superfície. A relação entre a distância de separação dos eletrodos no arranjo com quatro pontas igualmente espaçadas, e a profundidade de prospecção, coeficiente k, oscilou entre 0,35 e 0,70 para os solos LVd, LAd e PVe avaliados. A sondagem elétrica empregada na caracterização de variabilidade espacial na horizontal e em profundidade em uma área com teores de argila oscilando entre 150 e 379 g kg-1 na camada 0 a 0,2 m e entre 225 e 326 g kg-1 na camada 0,6 a 0,8 m apresentou resultado satisfatório. / The variability of soil physical properties has an impact on the performance of agricultural production activities. Indirect methods for obtaining information on the soil properties with agronomic interest are used to allow the use of inputs more appropriately. The apparent soil electrical conductivity ( ECa ) is influenced by several properties , many of them interrelated and presenting variability in short distances, being difficult to separate the various factors. ECa measures are usually taken in surface, using electrode arrangements for prospecting a soil volume proportional to the distance between them. In this work, a methodology was used that identified some of the properties with the greatest impact on the ECa, with emphasis to those related to soil porous space. The detailed characterization of the variation of ECw throughout the soil profile and its comparison with that obtained from the vertical electrical sounding was carried to identify certain limitations of this technique. The presence of several layers with varying physical properties and moisture in the soil profile changed values obtained from surface sounding. The relationship between the separation of the electrodes in the array with four points equally spaced, the Wenner array, and the depth of exploration, coefficient k, ranged between 0.35 and 0.70 for the soils LVd , LAd PVe and evaluated. A survey was done for the ECa characterization of spatial variability in the horizontal and along soil profile in an area with clay content ranging from 150 to 379 g kg - 1 in the layer from 0 to 0.2 m and between 225 and 326 g kg - 1 in layer 0, 6 to 0.8 m. The use of ECa for characterizing this variability showed satisfactory results.

Tem sido crescente o volume de investigações sugestivas de deformação tectônica no desenvolvimento dos sistemas deposicionais quaternários da ilha do Marajó. Isto é revelado pela combinação de informações sedimentológicas e estratigráficas com análises morfoestruturais. Entretanto, estudos de subsuperfície visando demonstrar a presença de estruturas tectônicas nessas áreas permanecem por ser apresentados. O presente estudo teve o objetivo principal de verificar se estruturas tectônicas sugeridas em superfície no leste da ilha de Marajó têm expressão em subsuperfície rasa, de forma a permitir discutir seu efeito na sedimentação neógena e quaternária, bem como seu mecanismo gerador. Para isto, procedeu-se com um estudo integrando informações geomorfológicas, geofísicas e geológicas. As informações geomorfológicas foram baseadas em dados cartográficos e imagens Landsat, e visou a análise de bacias de drenagem, identificação de anomalias de drenagem e extração e análise de lineamentos morfoestruturais. Dados geofísicos consistiram em sondagem elétrica vertical (SEV) realizada ao longo deste estudo, adicionadas ao reprocessamento de dados disponíveis na literatura. Este estudo foi complementado com a coleta de seções de radar de penetração no solo (GPR). A análise de dados de subsuperfície foi apoiada em estudos geológicos baseados em exposições naturais em falésias, cortes de estrada e pedreiras, além de testemunhos de sondagem. Três bacias de drenagem foram reconhecidas na área de estudo, correspondentes aos rios Arari, Camará e Paracauari. Todas estas bacias mostram evidências de anomalias morfoestruturais, incluindo-se principalmente: mudanças rápidas no padrão de drenagem dentro de uma mesma bacia, variando de treliça, retangular, multibacinal a subparalelo; canais retilíneos comumente conectados em ângulos retos; canais meandrantes que se tornam retilíneos; meandros localizados; e bacias altamente assimétricas (fator de assimetria > 60). Anomalias de drenagem consistindo em freqüentes desvios de direção com ângulos retos e meandros isolados e comprimidos, são também reconhecidas na paleodrenagem preservada na área de estudo. Dois compartimentos morfoestruturais puderam ser reconhecidos com base na densidade dos lineamentos estruturais: compartimento I, localizado na porção centro-leste da área de estudo, onde ocorre densidade de lineamentos alta com duas direções preferenciais para NW-SE e NE-SW; e compartimento II, correspondente ao restante da área, onde a densidade de lineamentos é muito baixa a média, e com orientação principal para NE-SW. O estudo enfocando 132 SEVs demonstrou que os extremos leste e sul da área de estudo são extremamente resistivos (valores de até 13.000 \'ômega\'m), que foram relacionados com a ocorrência, próximo da superfície, de paleossolo laterítico, bem como de estratos ferruginizados logo abaixo deste horizonte, formados em associação com a discordância do topo de estratos miocênicos da Formação Barreiras. Por outro lado, valores baixos (< 90 \'ômega\'m) foram registrados no restante da área de estudo, que foram relacionados com depósitos condutivos, representados por litologias argilosas, heterolíticas e, menos comumente, areníticas, correspondentes aos Sedimentos Pós-Barreiras, de idade quaternária tardia e holocênica. Esses dados são condizentes com a análise de seções GPR, que demonstrou refletores de alta freqüência e continuidade lateral próximo da superfície relacionada ao paleossolo laterítico. Com base nesta constatação, pode-se reconhecer duas unidades estratigráficas na porção leste da área de estudo, sendo a inferior relacionada com a Formação Barreiras e a superior correspondente aos Sedimentos Pós-Barreiras. Em contraste, as porções leste e norte da área de estudo mostraram ausência de refletores, que foi associado à presença de sedimentos quaternários dominantemente argilosos e contendo água estratal salobra e/ou salina. Várias características suportam a presença de estruturas tectônicas na área de estudo. Isto é sugerido pela abundância de anomalias de drenagem (atual e pretérita) e de lineamentos morfoestruturais com direcionamentos que coincidem com as orientações principais de falhas tectônicas registradas na região amazônica. A presença de falhas foi ainda indicada por contatos bruscos entre a Formação Barreiras e os Sedimentos Pós-Barreiras nas seções SEVs. Esta proposta é consistente com a análise de dados de superfície, que mostrou coincidência dos locais onde ocorrem estes contatos bruscos com lineamentos morfoestruturais. Da mesma forma, as seções GPR revelaram uma abundância de refletores deslocados verticalmente, que são somente justificados considerando-se falhas tectônicas. Adicionalmente, a porção basal de muitas das seções GPR mostraram refletores ondulados, que foram relacionados com amplas dobras sinclinais e anticlinais. A origem dessas estruturas tectônicas é discutida considerando-se três mecanismos potenciais: tectônica andina, tectônica gravitacional relacionada com a sobrecarga do leque submarino do cone do Amazonas, e rifteamento marginal. A hipótese de relacionamento das estruturas tectônicas registradas neste trabalho com a dinâmica de evolução do Sistema de Graben do Marajó aparece como a mais provável. As dobras e falhas registradas na Formação Barreiras e Sedimentos Pós-Barreiras podem ser explicadas considerando tectônica transcorrente, com associação de deformação transpressiva e transtensiva durante e após o Mioceno. / There has been an increasing volume of investigation suggestive of tectonic deformation in the development of Quaternary depositional systems in Marajó island. This is revealed by a combination of sedimentological and stratigraphical information with morphostructural analysis. However, subsurface studies aiming to demonstrate the presence of tectonic structures in this area remain to be presented. The present study had the main goal of verifying if tectonic structures suggested in surface in eastern Marajó island are expressed in shallow subsurface, thus allowing to discuss their effect in the Neogene and Quaternary sedimentation, as well as their trigger mechanism. This was approached with a study integrating geomorphologic, geophysical and geological information. Geomorphological information, based on cartographic data and Landsat images, aimed analysis of drainage basins, identification of drainage anomalies and extraction and analysis of morphostructural lineaments. Geophysical data consisted of vertical electric sounding (VES) acquired along this study, added to the reprocessing of data available in the literature. This study was complemented with acquisition of ground penetrating radar (GPR) sections. SEV data collected along this study were combined with reprocessed data derived from available literature. The geophysical study includes also acquisition of ground penetration radar (GPR) sections. The analysis of subsurface data was complemented with geological studies of based on natural exposures along coastal cliffs, road cuts and quarries, as well as cores. Three drainage basins were recognized in the study area, corresponding to the Arari, Camará and Paracauari rivers. All these basins show evidence of morphostructural anomalies, mostly including: rapid changes in drainage pattern within a same basin, ranging from trellis, rectangular, multibasin to subparallel; straight channels commonly connected at right angles; meandering channels that change to straight channels; local meandering; and highly asymmetric basins (asymmetry index > 60). Drainage anomalies consisting of frequent changes in river courses forming straight angles and isolated and compressed meanders are also recorded in the paleodrainage preserved in the study area. Two morphostructural compartments were recognized with basin morphostructural lineament density: compartment I, situated in the center-eastern part of the study area, where lineament density is high and with two preferential directions to NWSE and NE-SW; and compartment II, corresponding to the remaining of the area, where lineament density is low to moderate, and with a NE-SW main trend. The study focusing on 132 VESs revealed that the eastern and southern portions of the study area are extremely resistive (values up to 13.000 \'ômega\'m). This is related to the occurrence of lateritic paleosol near the surface, as well as ferrified strata immediately underlying this horizon, which were formed in association with the unconformity at the top of the Miocene strata of the Barreiras Formation. In contrast, only low resistivity values (< 90 \'ômega\'m) were recorded in the remaining of the study area, being related to conductive deposits represented by muddy, heterolithic and, less commonly, sandy lithologies corresponding to the Post-Barreiras Sediments of late Quaternary and Holocene ages. These data are consistent with analysis of GPR sections, which revealed reflectors with high frequency and lateral continuity near the surface associated with the lateritic paleosol. Taking this into account, two stratigraphic units were recognized in the eastern portion of the study area, with the lower one related to the Barreiras Formation and the upper one corresponding to the Post-Barreiras Sediments. In constrast, the eastern and northern portions of the study area displayed absence of reflectors, which was associated with the presence of dominantly muddy Quaternary sediments bearing intrastratal brackish and/or saline waters. Several characteristics support the presence of tectonic structures in the study area. This was suggested by the abundance of drainage anomalies (modern and ancient) and morphostructural lineaments with directions that coincide with the orientation of main tectonic faults recorded in Amazonia. The presence of faults was also indicated by sharp contacts between the Barreiras Formation and the Post Barreiras Sediments, as recorded in the VES sections. This proposal is consistent with the analysis of surface data that shows concordance of the places with sharp lithological contacts with morphostructural lineaments. Likewise, the GPR sections reveal an abundance of reflectors with vertical offsets that are only justified taking into account tectonic faults. Additionally, the basal portions of several GPR sections displayed undulatory reflectors, which were related to wide syncline and anticline folds. The origin of these tectonic structures is discussed considering three potential mechanisms: Andean tectonics, gravitational tectonics related to sediment loading in the Amazon submarine cone, and marginal rifting. The hypothesis of relating the tectonic structures recorded in this work with the dynamic evolution of the Marajo Graben System seems the most likely. The folds and faults recorded in the Barreiras Formation and Post-Barreiras Sediments might be explained considering strike slip deformation, with association of transpression and transtension during and after the Miocene.