Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-08-16T20:54:14Z No. of bitstreams: 1 SamirDoNascimentoValcacio_DISSERT.pdf: 5025545 bytes, checksum: 86238af38914f484b62ba415688d27cb (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-19T21:40:00Z (GMT) No. of bitstreams: 1 SamirDoNascimentoValcacio_DISSERT.pdf: 5025545 bytes, checksum: 86238af38914f484b62ba415688d27cb (MD5) / Made available in DSpace on 2016-08-19T21:40:00Z (GMT). No. of bitstreams: 1 SamirDoNascimentoValcacio_DISSERT.pdf: 5025545 bytes, checksum: 86238af38914f484b62ba415688d27cb (MD5) Previous issue date: 2016-02-15 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A Bacia Potiguar, localizada na margem equatorial Brasileira, possui diversas rochas sedimentares que s?o afetadas por intrus?es ?gneas b?sicas cenozoicas, conhecidas como Magmatismo Macau. Dentre os efeitos mais proeminentes, relacionados a estas intrus?es, temos a forma??o de buchitos, rochas pirometam?rficas que ocorrem em altas temperaturas e baixas press?es, na f?cies sanidinito. Por meio de revis?o bibliogr?fica, observa??es de campo, petrografia, petrof?sica, acesso a bancos de informa??es de trabalhos pr?vios na ?rea e resultados da presente pesquisa, foi poss?vel caracterizar e estimar os efeitos termais produzidos na aur?ola de alguns corpos hipabissais nesta bacia. As fei??es mais relevantes associadas ?s intrus?es s?o: compacta??o, faturamento hidr?ulico, fus?o parcial e recristaliza??o das rochas encaixantes. De acordo com as ocorr?ncias minerais registradas, interpretam-se de 800 a 1200oC e press?es inferiores a 0,5 kbar nas proximidades dos corpos ?gneos. O modelamento t?rmico do plug S?o Jo?o registrou o efeito metam?rfico at? 150 m do contato com dissipa??o de calor total em aproximadamente 265 mil anos. Ap?s o pico de temperatura, seguiu-se a fase de arrefecimento registrada com remobiliza??o e precipita??o de minerais de baixa temperatura em falhas, fraturas e geodos, derivados de rea??es com de por??es sedimentares e fluidos metassom?ticos / hidrotermais, com abundante silicifica??o e carbonatiza??o. / The Potiguar Basin is located in the Brazilian Equatorial Margin and presents sedimentary rocks affected by Cenozoic basic igneous intrusions, known as Macau Magmatism. The most prominent effect related to these intrusions is the formation of buchites, pyrometamorphic rocks that occur at very high temperatures and very low pressures in the sanidinite metamorphic facies. Through literature review, field observations, petrographic and petrophysical data, accessing the database of previous studies and results from this research, it was possible to characterize and estimate the effects produced in the thermal aureole of some hypabyssal bodies in the basin. The most relevant features associated with the intrusions are: compactation, hydraulic fracturing, partial melting and recrystallization of country rocks. According to the observed mineral occurrences, temperature of 800 to 1200 ?C and pressure below 0,5 kbar were estimated at the contacts of the igneous bodies. The thermal modeling of the S?o Jo?o plug indicates thermal effects extending up to 150 m away from the contact and cooling time of approximately 265,000 years. After the peak of temperature, followed a cooling phase registered by remobilization and precipitation of minerals at low-temperature in faults, fractures and geodes, interpreted as derived from reactions with sedimentary rocks and metasomatic / hydrothermal fluids with abundant carbonatization and silicification.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-25T19:35:28Z No. of bitstreams: 1 EvertonNobregaBarbosa_DISSERT.pdf: 9232296 bytes, checksum: 5cd3f1d1ccd18c21370731922d1da077 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-28T23:19:32Z (GMT) No. of bitstreams: 1 EvertonNobregaBarbosa_DISSERT.pdf: 9232296 bytes, checksum: 5cd3f1d1ccd18c21370731922d1da077 (MD5) / Made available in DSpace on 2016-07-28T23:19:32Z (GMT). No. of bitstreams: 1 EvertonNobregaBarbosa_DISSERT.pdf: 9232296 bytes, checksum: 5cd3f1d1ccd18c21370731922d1da077 (MD5) Previous issue date: 2015-08-24 / Ag?ncia Nacional do Petr?leo - ANP / A Sequ?ncia Neocarbon?fera-Eotri?ssica corresponde ao terceiro grande ciclo sedimentar da Bacia do Parna?ba e concerne litoestratigraficamente ao Grupo Balsas. Esta sequ?ncia ? descrita como um pacote de rochas cujos sedimentos foram depositados em um ambiente complexo, cl?stico/evapor?tico de mar raso, gradando para um ambiente lacustre/des?rtico. O principal objetivo deste trabalho foi realizar uma an?lise estratigr?fica da Sequ?ncia Neocarbon?fera-Eotri?ssica, visando uma melhor compreens?o da sua evolu??o. Para tal, foram empregados os conceitos modernos e gen?ticos da estratigrafia, utilizando-se como base de dados informa??es de po?os e se??es s?smicas. Para o intervalo estratigr?fico em quest?o foram identificadas tr?s sequ?ncias deposicionais. A Sequ?ncia 1 corresponde a rochas que foram depositadas inicialmente a partir de um sistema fluvial, que passa para um sistema marinho raso implantado durante uma fase transgressiva, e que posteriormente evolui para um sistema deltaico. A Sequ?ncia 2 corresponde a rochas que foram depositadas a partir de um ambiente lacustre/des?rtico, representando uma fase regressiva importante que culmina com a implanta??o de um ambiente des?rtico, o qual corresponde ? Sequ?ncia 3. Na an?lise sismoestratigr?fica foi poss?vel reconhecer as superf?cies cronoestratigr?ficas e as unidades gen?ticas identificadas em po?os e analisar a sua express?o lateral. De modo geral, as sismof?cies reconhecidas nas se??es s?smicas apresentam-se com configura??es paralelas a subparalelas, com grande continuidade lateral, sugerindo uma const?ncia na taxa de sedimenta??o durante a deposi??o desta sequ?ncia. / The Parna?ba Basin consists in an intracratonic basin whose sucession of rocks is arranged in five supersequences. The Upper Carboniferous-Lower Triassic Sequence represents the third major sedimentary cycle and corresponds to Balsas Group, which is divided into four units: Piau? Formation, Pedra de Fogo Formation, Motuca Formation and Samba?ba Formation, from base to top. Different interpretations have been made by several authors in recent decades to interpreted the depositional system and environments related to each unit that belongs to this sequence. In general way, it is described as a thick pack of siliciclastic sediments deposited under complex conditions, varying from clastic/evaporitic shallow marine to lacustrine and desert environment. Aiming to clarify the sedimentary sequence evolution, this work underwent a stratigraphic analysis of the Upper Carboniferous-Lower Triassic deposits by applying modern concepts of the sequence stratigraphy based on well and seismic database. Three main depositional sequences of higher frequency were identified in each well analyzed. The sequence 1 corresponds to rocks initially deposited by a fluvial system with braided channel characteristics which evolved to shallow marine with coastal sabkha conditions related to a transgressive stage, that later evolved to a deltaic system. The Sequence 2 corresponds to rocks deposited in a lacustrine/desert environment associated with sabkha generated during a period of increased aridity in which the area occupied by the Parna?ba Basin had been suffering. The registration of a major regressive phase is shown in Sequence 2 which evolved to a dominantly desert environment recorded in Sequence 3. Seismic stratigraphy analyses allow to define a series of stratigraphic surfaces and related genetic units, as well as to infer its lateral expression. Seismic facies associated with such sequences are dominantly parallel and sub-parallel, with good lateral continuity, suggesting the sedimentary rate was relatively constant during deposition.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-12T15:09:55Z No. of bitstreams: 1 JulianaGarridoDamaceno_DISSERT.pdf: 4394873 bytes, checksum: f05a0b01011611585c6553b593f93fa0 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-19T16:25:56Z (GMT) No. of bitstreams: 1 JulianaGarridoDamaceno_DISSERT.pdf: 4394873 bytes, checksum: f05a0b01011611585c6553b593f93fa0 (MD5) / Made available in DSpace on 2017-01-19T16:25:56Z (GMT). No. of bitstreams: 1 JulianaGarridoDamaceno_DISSERT.pdf: 4394873 bytes, checksum: f05a0b01011611585c6553b593f93fa0 (MD5) Previous issue date: 2016-08-05 / Essa disserta??o apresenta um estudo geof?sico de uma intrus?o b?sica cenozoica, envolvendo etapas de aquisi??o, processamento e modelagens 2D e 3D de dados magn?ticos e gravim?tricos terrestres. O alvo estudado ? um plug conhecido como S?o Jo?o, intrusivo em rochas sedimentares da borda sul da Bacia Potiguar, regi?o setentrional do Rio Grande do Norte. Com uma ?rea aproximada de 0,5 km?, este plug ? um dos diversos corpos ?gneos constituintes do Magmatismo Macau (50-7 Ma). Os arenitos e calc?rios pr?ximos ao corpo subvulc?nico sofreram modifica??es mineral?gicas significativas por efeito termal. Utilizamos dados magn?ticos aerolevantados do Projeto Bacia Potiguar e aquisi??es terrestres, que resultaram em 5698 leituras com o magnet?metro de campo total e 128 esta??es gravim?tricas com o grav?metro CG5. O mapa das derivadas verticais do campo magn?tico an?malo dos dados a?reos contextualizou regionalmente a geologia e geof?sica da Bacia Potiguar, enquanto que os dados magn?ticos e gravim?tricos terrestres detalharam o plug S?o Jo?o e foram utilizados para as modelagens. Foram realizadas medidas de susceptibilidade magn?tica e densidade em amostras de rochas metam?rficas (buchitos), ?gneas (diab?sio) e sedimentares (arenito e calc?rio). Tais medidas auxiliaram na constru??o de modelos 2D e 3D, revelando a arquitetura interna do plug S?o Jo?o, cujas profundidades chegam a cerca de 400 m. O modelo gravim?trico apresenta uma geometria no formato de lop?lito, com uma regi?o na parte nordeste do corpo apresentando maiores contrastes de densidade. Tal regi?o ? tamb?m observada no modelo magn?tico, com altos contrastes de susceptibilidade magn?tica. M?ximos gravim?tricos pr?ximos ao plug indicam tr?s regi?es com contrastes de densidade positivos, que podem ser corpos ?gneos sem express?o em superf?cie. / This dissertation presents a geophysical study of a Cenozoic basic intrusion, involving steps of acquisition, processing, and 2D and 3D modeling of terrestrial magnetic and gravity data. The target studied is a plug known as S?o Jo?o, located in the southern border of the Potiguar Basin (NE Brazil). This plug has an area of approximately 0.5 km? and was formed by magmatism Macau. Sandstones and limestones near the hipoabissal body suffered metamorphization with significant thermal changes. We use airborne magnetic data named Potiguar Basin Project and terrestrial acquisition, which resulted in 5698 readings with the total field magnetometer and 128 gravity stations with CG5 gravimeter. The map of vertical derivative of the total magnetic intensity anomalies from the airborne data contextualized regionally the geology and geophysics of the Potiguar Basin, while the terrestrial magnetic and gravimetric data detailed the plug S?o Jo?o and were used for the modeling. Magnetic susceptibility and density were measured in metamorphic (buchites) igneous (diabase) and sedimentary (sandstone and limestone) rock samples. Such measures help to constrain the 2D and 3D modeling, which reveal the internal architecture of the S?o Jo?o plug, whose maximum depths reach 400 m. The gravity model of the plug shows a lopolith shape, with a region in the northeastern part of the body having higher density contrast. This region is also observed in the magnetic model with high contrast of magnetic susceptibility. Gravity highs closer to S?o Jo?o plug indicate three regions with high density contrasts, which probably are igneous bodies with no surface expression.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-08-16T20:54:14Z No. of bitstreams: 1 PedroAugustoRodriguesFerreira_DISSERT.pdf: 3916338 bytes, checksum: 375a323b74f41b291e797b658f9673a0 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-19T21:20:18Z (GMT) No. of bitstreams: 1 PedroAugustoRodriguesFerreira_DISSERT.pdf: 3916338 bytes, checksum: 375a323b74f41b291e797b658f9673a0 (MD5) / Made available in DSpace on 2016-08-19T21:20:18Z (GMT). No. of bitstreams: 1 PedroAugustoRodriguesFerreira_DISSERT.pdf: 3916338 bytes, checksum: 375a323b74f41b291e797b658f9673a0 (MD5) Previous issue date: 2016-02-24 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A atividade s?smica do Nordeste do Brasil tem sidoalvo constante de estudos, uma vez que esta ? regi?o mais ativa do pa?s.Contudo, algumas ?reas possuem seus terremotos relacionados com a??o humana, ouseja, s?o de car?ter induzido. A barragem do A?u constitui um exemplo cl?ssicode sismicidade induzida por reservat?rio e j? foi alvo de diversos estudos.Recentemente, ap?s um consider?vel per?odo sem que houvesse atividade s?smicana barragem, o LabSis/UFRN registrou, por meio de uma esta??o regional, eventosrelacionados com o a?ude, o que motivou a instala??o de uma rede local ao redorda barragem. A partir dos dados provenientes dessa rede, observou-se que aatividade s?smica est? relacionada com uma nova ?rea epicentral dento dabarragem. Os par?metros hipocentrais dessa atividade foram determinados, bemcomo o respectivo mecanismo focal. Verificou-se que eventos estavamrelacionados com a reativa??o do embasamento em uma nova falha subvertical comorienta??o NE-SW subparalela a falha de S?o Rafael. Esses resultados foramutilizados na elabora??o de um artigo cient?fico, o qual discutiu a rela??odessa sismicidade com a geologia da regi?o e tamb?m com o n?vel de ?gua doreservat?rio. O artigo mostrou que a difus?o da press?o de poro foi o mecanismoque controlou o disparo da sismicidade induzida na barragem. / The seismic activity in the Northeastern of Brazil has been a constant target of study, since it is the most active region of the country. However, some areas have their earthquakes related to human action, what means they are induced. The A?u dam is a classic example of reservoir-induced seismicity and it has been the subject of several studies. Recently, after a considerable period of inactivity, the LabSis / UFRN recorded events related to the dam, which led to the installation of a network around the reservoir. From the data provided by this network, it was observed that the seismic activity is related to a new epicental area inside the lake. The epicentral parameters and the focal mechanism were determined. It was found that the events were related to the reactivation of a basement structure in a new seismogenic subvertical fault with NE-SW-striking subparallel to the S?o Rafael Fault. These results were used in the preparation of a scientific paper, which discussed the relationship between this seismicity with the geology of the region and with the reservoir water level. The paper showed that the diffusion of pore pressure was the main mechanism that controlled the triggering of the induced seismicity at the reservoir.

Made available in DSpace on 2015-03-13T17:08:21Z (GMT). No. of bitstreams: 1 CristinaAD.pdf: 1396383 bytes, checksum: 2ded09c99516b39813718bfd6b0ceebf (MD5) Previous issue date: 2002-07-18 / A research project is being developed by PPGG/UFRN and PETROBRAS in the Xar?u Oil Field located in Cear? Basin, Northeastern Brazil. The objective of the research is to characterize a fractured carbonate reservoir, the Trairi Limestone, in order to drill a borehole with two horizontal legs taking advantage of the natural fracture system to enhance the oil recovery. The present master thesis is part of this research and its contribution is to estimate fault orientation from unoriented cores, using the method proposed by Hesthammer & Henden (2000). In order to orient a fault cutting a bed observed in the core, the bed should be previously oriented. As additional constraint to orient the bed, we use regional bedding orientation obtained from structure maps of Trairi Limestone. Because the number of cores drilled from the Trairi Limestone was too small, we analyzed all cores from the field. As geologic constraint, we admit that all faults were formed as result of the South America and Africa separation, in the context of a regional dextral strike-slip fault formation. In this context, secondary faults are manly T and R faults according Riedel s classification. We analyzed 236.5 m of cores. The dip of bedding varies from 0o to 8o, being the most frequent value equal to 2o. We interpret this result as evidence that the deformation process was manly ruptil. 77 faults were identified in the cores. These faults strike manly to NW and NE with dips, in general, inside the interval 700 - 900. We suggest that the horizontal legs of the borehole should be oriented to NW and NE in order to improve the probability of intercepting open fractures and faults / Um projeto de pesquisa est? sendo desenvolvido pelo PPGG/UFRN e a PETROBR?S no Campo Petrol?fero de Xar?u localizado na bacia do Cear?, Nordeste do Brasil. O objetivo da pesquisa ? a caracteriza??o de um reservat?rio carbon?tico fraturado, o Calc?rio Trair?, para a perfura??o de um po?o com duas pernas horizontais levando em considera??o o sistema natural de fraturas deste reservat?rio visando aumentar a taxa de recupera??o do ?leo. A presente disserta??o ? parte desta pesquisa e sua contribui??o ? estimar a orienta??o das falhas presentes em testemunhos de sondagens n?o orientados, usando o m?todo proposto por Hesthammer & Henden (2000). Para orientar uma falha interceptando um estrato observado no testemunho, o estrato deve ser previamente orientado. Como v?nculo para orientar os estratos, utilizou-se o mergulho regional das camadas, obtido em cada posi??o de po?o a partir dos mapas de contorno estrutural do Calc?rio Trair?. Devido ao fato do n?mero de falhas presentes nos testemunhos do Calc?rio Trair? ser pequeno, a analise estrutural foi realizada em todos os testemunhos do Campo de Xar?u. Como hip?tese geol?gica de trabalho, admitiu-se que todas as falhas foram formadas como resultado da separa??o da Am?rica do Sul e ?frica, no contexto de forma??o de uma falha transcorrente dextral regional. Nesse contexto, falhas secundarias s?o principalmente dos tipos T e R de acordo com a classifica??o de Rieldel. Foram analisados 263.5 m de testemunhos. Os mergulhos dos estratos variam de 0o a 8o, sendo que o valor mais freq?ente ? igual a 2o. Este resultado foi interpretado como um ind?cio de que a deforma??o no Campo de Xar?u foi principalmente de natureza r?ptil. As dire??es preferenciais de strike para as falhas analisadas s?o NW e NE. Essas falhas possuem mergulho alto, em geral entre 70o e 90o. Sugere-se que as pernas horizontais do po?o sejam orientadas para NW e NE, de modo a aumentar a probabilidade das pernas interceptarem o maior n?mero poss?vel de fraturas e falhas abertas

Made available in DSpace on 2015-03-13T17:08:32Z (GMT). No. of bitstreams: 1 DanielleKSG_TESE_1-80.pdf: 3344366 bytes, checksum: 7b166fd0d1c9101001b02bd52c3b1b8d (MD5) Previous issue date: 2010-02-22 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The increasing use of shallow seismic methods of high resolution, for investigations of geological problems, environmental or industrial, has impelled the development of techniques, flows and computational algorithms. The practice of applying techniques for processing this data, until recently it wasn t used and the interpretation of the data was made as they were acquired. In order to facilitate and contribute to the improvement of the practices adopted, was developed a free graphical application and open source, called OpenSeismic which is based on free software Seismic Un*x, widely used in the treatment of conventional seismic data used in the exploration of hydrocarbon reservoirs. The data used to validate the initiative were marine seismic data of high resolution, acquired by the laboratory of Geology and Marine Geophysics and Environmental Monitoring - GGEMMA, of the Federal University of Rio Grande do Norte UFRN, for the SISPLAT Project, located at the region of paleo-valley of the Rio Acu. These data were submitted to the processing flow developed by Gomes (2009), using the free software developed in this work, the OpenSeismic, as well other free software, the Seismic Un*x and the commercial software ProMAX, where despite its peculiarities has presented similar results / A crescente utiliza??o de m?todos de s?smica rasa de alta resolu??o, para investiga??es de problemas geol?gicos, impulsionou o desenvolvimento de t?cnicas, fluxos e algoritmos computacionais. A pr?tica de aplicar t?cnicas para tratamento desses dados, at? pouco tempo n?o era utilizada e a interpreta??o dos dados era feita da forma que eram adquiridos. Visando facilitar e contribuir para o aperfei?oamento dessas pr?ticas adotadas, desenvolveu-se uma aplica??o gr?fica livre e de codifica??o aberta, denominada OpenSeismic que tem como base o software livre Seismic Un*x, bastante utilizado no tratamento dos dados da s?smica convencional, utilizados na explora??o de reservat?rios de hidrocarbonetos. Os dados utilizados para validar a iniciativa, foram dados de s?smica marinha de alta resolu??o, adquiridos pelo laborat?rio de Geologia e Geof?sica Marinha e Monitoramento Ambiental GGEMMA, da Universidade Federal do Rio Grande do Norte UFRN, para o Projeto SISPLAT, tendo como localiza??o a regi?o do Paleovale do Rio A?u. Esses dados foram submetidos ao fluxo de processamento desenvolvido por Gomes (2009), utilizando os softwares livres OpenSeismic, Seismic Un*x e o software comercial ProMAX, onde apesar das suas particularidades pode-se observar resultados equivalentes

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-25T19:35:25Z No. of bitstreams: 1 AlannyChristinyCostaDeMelo_DISSERT.pdf: 4456971 bytes, checksum: 8caf70bc14125d0010bb4e21e9d3aa55 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-28T20:49:41Z (GMT) No. of bitstreams: 1 AlannyChristinyCostaDeMelo_DISSERT.pdf: 4456971 bytes, checksum: 8caf70bc14125d0010bb4e21e9d3aa55 (MD5) / Made available in DSpace on 2016-07-28T20:49:41Z (GMT). No. of bitstreams: 1 AlannyChristinyCostaDeMelo_DISSERT.pdf: 4456971 bytes, checksum: 8caf70bc14125d0010bb4e21e9d3aa55 (MD5) Previous issue date: 2016-03-04 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / N?s estudamos a Bacia Potiguar Cret?cea na margem Equatorial do Brasil para entender a geometria das grandes falhas e a influ?ncia da heterogeneidade crustal e o fabric estrutural preexistente na evolu??o da arquitetura interna bacia. Estudos anteriores apontaram que o rifte ? um meio graben assim?trico alongado de dire??o NE-SW. Para determinar o deslocamento m?ximo (Dm?x) e comprimento (L) dos principais segmentos de falha de borda do Rifte Potiguar foram usados s?smica 2D, dados de po?os e modelagem gravim?trica 3D. A modelagem gravim?trica 3D foi parametrizada com os dados de po?os e interpreta??es das se??es s?smicas. O grau de incerteza do modelo gravim?trico foi da ordem 10% aos dados s?smicos e de po?os. Atrav?s das curvas de crescimento de falhas foi poss?vel dividir as falhas de borda do rifte em quatro segmentos principais, os quais forneceram valores Dm?x/L da mesma ordem de grandeza. As curvas de crescimento de falhas sugerem que um mecanismo tect?nico uniforme regional teria influenciado o crescimento dos segmentos dessas falhas. As varia??es dos deslocamentos m?ximos ao longo dos segmentos de falha indicam que estes segmentos se desenvolveram de forma independente durante o in?cio do rifteamento e, posteriormente, foram unidos por liga??es rig?das e flex?veis. Este ?ltimo, chegou a formar uma rampa de al?vio entre as falhas de Baixa Grande e Carnaubais. Nos pontos de interliga??o entre falhas as taxas Dm?x / L s?o mais elevadas devido ? interfer?ncia do crescimento dos segmentos de falha adjacentes. A evolu??o do Rifte Potiguar foi dividida em cinco etapas com base nas rela??es Dm?x/L, que foram correlacionadas com as principais fases tect?nicas da separa??o entre a Am?rica do Sul e ?frica no Cret?ceo Inferior. / The discussion about rift evolution in the Brazilian Equatorial margin during the South America-Africa breakup in the Jurassic/Cretaceous has been focused in many researches. But rift evolution based on development and growth of faults has not been well explored. In this sense, we investigated the Cretaceous Potiguar Basin in the Equatorial margin of Brazil to understand the geometry of major faults and the influence of crustal heterogeneity and preexisting structural fabric in the evolution of the basin internal architecture. Previous studies pointed out that the rift is an asymmetrical half-graben elongated along the NE-SW direction. We used 2D seismic, well logs and 3D gravity modeling to analyze four major border fault segments and determine their maximum displacement (Dmax) and length (L) ratio in the Potiguar Rift. We constrained the 3D gravity modeling with well data and the interpretation of seismic sections. The difference of the fault displacement measured in the gravity model is in the order of 10% compared to seismic and well data. The fault-growth curves allowed us to divide the faulted rift border into four main fault segments, which provide roughly similar Dmax/L ratios. Fault-growth curves suggest that a regional uniform tectonic mechanism influenced growth of the rift fault segments. The variation of the displacements along the fault segments indicates that the fault segments were formed independently during rift initiation and were linked by hard and soft linkages. The latter formed relay ramps. In the interconnection zones the Dmax/L ratios are highest due to interference of fault segment motions. We divided the evolution of the Potiguar Rift into five stages based on these ratios and correlated them with the major tectonic stages of the breakup between South America and Africa in Early Cretaceous.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-25T19:35:28Z No. of bitstreams: 1 ClaudeteRodriguesDeSouza_DISSERT.pdf: 7248197 bytes, checksum: 517f3832b2c0793432a194051a3ea304 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-28T22:35:34Z (GMT) No. of bitstreams: 1 ClaudeteRodriguesDeSouza_DISSERT.pdf: 7248197 bytes, checksum: 517f3832b2c0793432a194051a3ea304 (MD5) / Made available in DSpace on 2016-07-28T22:35:34Z (GMT). No. of bitstreams: 1 ClaudeteRodriguesDeSouza_DISSERT.pdf: 7248197 bytes, checksum: 517f3832b2c0793432a194051a3ea304 (MD5) Previous issue date: 2014-04-03 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Este estudo foi desenvolvido em uma ?rea localizada na plataforma externa da Bacia Potiguar, margem equatorial brasileira. A amostragem de sedimentos foi realizada em tr?s campanhas, em torno de um po?o explorat?rio, para comparar as propriedades dos sedimentos do fundo marinho, incluindo granulometria, composi??o, conte?do de carbonato e mat?ria org?nica, anterior a perfura??o do po?o, com amostras coletadas 3 e 12 meses ap?s a perfura??o. O planejamento amostral utilizou 16 esta??es localizadas em 4 radiais distantes 50 m, 100 m, 250 m e 500 m do po?o. Os sedimentos foram analisados nas camadas 0-2 cm e 0-10 cm. Os resultados mostraram que a cobertura sedimentar em torno do po?o era pobre a muito pobremente selecionada, com granulometria predominante na fra??o areia grossa com granulo e cascalho, seguida por cascalho e lama. O conte?do de carbonato de c?lcio foi maior que 96%, associado a sedimentos biocl?ticos, e o conte?do de mat?ria org?nica foi menor que 12%. Apenas pequenas varia??es sedimentol?gicas ocorreram na ?rea afetada pelas opera??es de perfura??o. A principal diferen?a foi observada em amostras da segunda campanha, em termos de uma mudan?a na distribui??o granulom?trica associada a um aumento no conte?do de sedimentos silicicl?sticos. Este impacto ocorreu nos sedimentos mais superficias (0-2 cm), no raio mais pr?ximo ao po?o (50 m), e poderia sugerir o efeito da perfura??o. Entretanto, os sedimentos coletados na campanha 3, um ano ap?s a perfura??o, voltaram a apresentar as mesmas caracter?sticas da primeira campanha. Estes resultados indicam que n?o houve varia??es sedimentol?gicas significantes devido a atividade de perfura??o, e que a din?mica oce?nica na ?rea de estudo foi forte o suficiente para recuperar as caracter?sticas originais do ambiente. ABSTRACT This study was developed in an area located on the outer shelf in the Potiguar Basin, Brazilian equatorial margin; this tropical shelf represents a modern, highly dynamic mixed carbonate-siliciclastic system. Field sampling was carried out during 3 cruises surrounding a shallow-water exploratory well to compare sediment properties of the seafloor, including grain-size, texture, mineral composition, carbonate content, and organic matter, prior to drilling with samples obtained 3 and 12 months after drilling. The sample grid used had 16 stations located along 4 radials from 50 m the well up to a distance of 500 m. Sediments were analyzed in the first 0-2 cm, and 0-10 cm layers. The results show that sedimentary cover around the well is poor to very poorly sorted, with the particle size predominantly in the medium to coarse sand fraction, followed by gravel and mud. The content of calcium carbonate is greater than 96%, associated to bioclastic sediments, and the content of organic matter is less than 12%. Only minor sedimentological variations occured ?in the area affected by drilling operations. The most noticeable effects were observed during the second cruise, in terms of a change in grain size distribution associated to an increase in siliciclastic content, This impact occurred in the most surficial sediment (0-2 cm), in the radial closest to the well (50 m), and could suggest the effects of drilling. However, in the third cruise, one year after drilling, the sediments return to show the same characteristics as in the first cruise. These results show no significant sedimentological variations due to drilling activity, and indicate that ocean dynamics in this area was high enough to recover the environment original characteristics. / This study was developed in an area located on the outer shelf in the Potiguar Basin, Brazilian equatorial margin; this tropical shelf represents a modern, highly dynamic mixed carbonate-siliciclastic system. Field sampling was carried out during 3 cruises surrounding a shallow-water exploratory well to compare sediment properties of the seafloor, including grainsize, texture, mineral composition, carbonate content, and organic matter. Cruise 1 (C1) was carried prior to drilling, while Cruise 2(C2) and 3 (C3) respectivelly 3 and 12 months after drilling. The sample grid used had 16 stations located along 4 radials from 50 m the well up to a distance of 500 m. Sediments were analyzed in the first 0-2 cm, and 0-10 cm layers. The results show that sedimentary cover around the well is poor to very poorly sorted, with the particle size predominantly in the medium to coarse sand fraction, followed by gravel and mud. The content of calcium carbonate is greater than 96%, associated to bioclastic sediments, and the content of organic matter is less than 12%. Only minor sedimentological variations occured in the area affected by drilling operations. Mainly observed during the second cruise, in terms of a change in grain size distribution associated to an increase in siliciclastic content, This impact occurred in the most surficial sediment (0-2 cm), in the radial closest to the well (50 m), and could suggest the effects of drilling. However, in the third cruise, one year after drilling, the sediments return to show the same characteristics as in the first cruise. These results show no significant sedimentological variations due to drilling activity, and indicate that ocean dynamics in this area was high enough to recover the environment original characteristics.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-25T19:35:28Z No. of bitstreams: 1 CristianeLeaoCordeiroDeFarias_DISSERT.pdf: 6033643 bytes, checksum: 958aa1ad7170e354d48b68819bbeaf94 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-28T23:04:10Z (GMT) No. of bitstreams: 1 CristianeLeaoCordeiroDeFarias_DISSERT.pdf: 6033643 bytes, checksum: 958aa1ad7170e354d48b68819bbeaf94 (MD5) / Made available in DSpace on 2016-07-28T23:04:10Z (GMT). No. of bitstreams: 1 CristianeLeaoCordeiroDeFarias_DISSERT.pdf: 6033643 bytes, checksum: 958aa1ad7170e354d48b68819bbeaf94 (MD5) Previous issue date: 2015-11-16 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Os estu?rios tem grande import?ncia como abrigo e ber??rio natural de animais marinhos, prov?m peixes para o homem,sustenta a cadeia alimentar, controla as a??es erosivas e alagamentos, atua nosistema de filtragem natural da polui??o e purifica??o do ar. O Rio Potengi temsido afetado por diversos fatores antr?picos ao longo dos anos, com v?riosdesastres ambientais que mataram peixes, aves e outros animais. Para analisar asitua??o recente do estu?rio do Rio Potengi, foram coletadas 42 amostras, 18 emOutubro/2011 ao longo do Rio Potengi e sua foz, e 24 em Janeiro/2012, inclu?mosa plataforma interna. An?lises univariadas (?ndices ecol?gicos) e multivariadas(PCA, MDS, CLUSTER e BIOENV) foramaplicadas ? matriz dos dados biol?gicos de foramin?feros e abi?ticos (CaCO3,salinidade, profundidade, temperatura e granulometria). Os resultados mostram a domin?ncia deforamin?feros oportunistas A. tepida,B. striatula, Q. patagonica e Q. milettiespecialmente nas regi?es pr?ximas ?s fazendas de carcinicultura e ao esgoto doCanal do Baldo em ambientes de granulometria fina, e Q. lamarckiana indicadora da penetra??o da cunha salina e ambientesde alta hidrodin?mica associada a sedimentos de areia grossa a muito fina. A presen?a de esp?cies caracter?sticasmarinhas H. boueana, E. discoidale, P. atlanticum, T. earlandie T. gramen na Foz do Rio Potengi ena plataforma interna indicam ambientes de altas salinidades. A ocorr?ncia dealgumas esp?cies tolerantes ? baixa salinidade como T. inflata e T. squamatano Canal do Rio Potengi sugerem que provavelmente devem ter sido transportadosdo manguezal pr?ximo ? foz do Rio Potengi para as regi?es de plataformainterna, sugerindo que o contribuinte fluvial ? capaz de exportar organismos de?gua doce preferivelmente em dire??o sul do que em dire??o norte. / The Potengi River estuary has been affected by various anthropogenic factors over the years, as periodic dredging, industrial and domestic waste, traffic and other factors, causing various environmental disasters, including the notorious ecological accident in July 2007, which covered the municipalities of S?o Gon?alo do Amarante, Maca?ba and Natal. Foraminifera serve as viable study tools in these environments; they are able to identify ecologically stressed environments, pointing out hydrographic changes and depositional environments in estuaries. The necessity to check the differences in environmental gradients in places anthropically impacted in Potengi River and adjacent inner shelf through species of foraminifera, and, the responses of these organisms to physical, chemical and geological factors is to provide baseline in the diagnosis of environments. The results show the dominance of opportunistic Ammonia tepida, Bolivina striatula, Quinqueloculina patagonica and Q. miletti especially in regions close to shrimp farms and Baldo Channel sewage in fine grain environments; and Q. lamarckiana indicates penetration of the saline waters in Potengi River. The occurrence of low-salinity tolerant foraminiferal species typical of mangrove environments as Trochammina inflata and T. squamata in Potengi River Channel suggest they probably could have been transported from mangrove area near the Potengi river mouth to the inner shelf regions. These findings suggest Potengi River is able to export mixohaline and mangrove organisms to inner shelf. Two distinct environments were observed, the outermost area is more influenced by marine influence and the innermost area is less influenced. Calcareous and agglutinated species dominate Potengi River, while mouth and inner shelf areas are dominated by calcareous, agglutinated and porcelaneous species, which are typical of highly saline and hydrodynamic environments and the contributive factors that controls foraminiferal distribution were balance of marine and freshwater currents, grain size, availability of CaCO3 and organic matter.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-25T19:35:29Z No. of bitstreams: 1 HasanLopesShihadeh_DISSERT.pdf: 4749062 bytes, checksum: 5c56d7aad70a0d9ccc2eba27d546688b (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-28T23:45:09Z (GMT) No. of bitstreams: 1 HasanLopesShihadeh_DISSERT.pdf: 4749062 bytes, checksum: 5c56d7aad70a0d9ccc2eba27d546688b (MD5) / Made available in DSpace on 2016-07-28T23:45:09Z (GMT). No. of bitstreams: 1 HasanLopesShihadeh_DISSERT.pdf: 4749062 bytes, checksum: 5c56d7aad70a0d9ccc2eba27d546688b (MD5) Previous issue date: 2015-09-08 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Neste trabalho foi realizado um estudo para a obtenc?a?o de para?metros para um modelo regional de velocidades 1D va?lido para a Provi?ncia Borborema, NE do Brasil. Para tanto, foram utilizados eventos que ocorreram na mesma entre 2001 e 2013 com magnitude acima de 2.9 e que tiveram epicentros bem determinados por redes locais de estac?o?es ou back azimuth, quando os dados sa?o de boa qualidade. Foram escolhidos 7 eventos ocorridos nas principais a?reas si?smicas da Provi?ncia Borborema. Os eventos selecionados foram, ao todo, registrados em 74 estac?o?es das redes: RSISNE, INCT-ET, Mile?nio, Joa?o Ca?mara - RN, Sa?o Rafael - RN, Caruaru - PE, Sa?o Caetano - PE, Castanha?o - CE, Santana do Acarau - CE, Taipu - RN e Sobral - CE e a estac?a?o RCBR da rede IRIS/USGS - GSN. Para a determinac?a?o dos para?metros do modelo realizou-se a inversa?o do tempo de percurso atrave?s de um ajuste de retas aos tempos observados. A validac?a?o deste modelo se deu de modo independente atrave?s da comparac?a?o com outros modelos conhecidos (globais e regionais para o Brasil). O modelo final, nomeado MBB, apresenta um modelo crustal lateralmente homoge?neo composto por duas camadas com crosta superior de 11,45 km de espessura e uma crosta com espessura total de 33,90 km, sendo a base da segunda camada limitada pela descontinuidade de Moho. A velocidade da onda P na crosta superior foi estimada em 6,00 Km/s e na crosta inferior 6,64 Km/s. A velocidade da onda P no manto superior foi estimada em 8,21 Km/s com uma raza?o VP/VS de aproximadamente 1,740 ? 0,002. / In this work it was performed a study to obtain parameters for an 1D regional velocity model for the Borborema Province, NE Brazil. It was used earthquakes occurred between 2001 and 2013 with magnitude greater than 2.9 mb either from epicentres determined from local seismic networks or by back azimuth determination, when possible. We chose seven events which occurred in the main seismic areas in the Borborema Province. The selected events were recorded in up to 74 seismic stations from the following networks: RSISNE, INCT-ET, Jo?o C?mara ? RN, S?o Rafael ? RN, Caruaru - PE, S?o Caetano - PE, Castanh?o - CE, Santana do Acarau - CE, Taipu ? RN e Sobral ? CE, and the RCBR (IRIS/USGS?GSN). For the determination of the model parameters were inverted via a travel-time table and its fit. These model parameters were compared with other known model (global and regional) and have improved the epicentral determination. This final set of parameters model, we called MBB is laterally homogeneous with an upper crust at 11,45 km depth and total crustal thickness of 33,9 km. The P-wave velocity in the upper crust was estimated at 6.0 km/s and 6.64 km/s for it lower part. The P-wave velocity in the upper mantle we estimated at 8.21 km/s with an VP/VS ratio of approximately 1.74.