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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Evolu??o estratigr?fica da sequ?ncia neocarbon?fera-eotri?ssica da Bacia do Parna?ba, NE do Brasil

Barbosa, Everton N?brega 24 August 2015 (has links)
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.
2

An?lise estratigr?fica da sequ?ncia siluriana da Bacia do Parna?ba, NE do Brasil

Cruz, Erlanny Maria Alves 29 February 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-03T19:37:11Z No. of bitstreams: 1 ErlannyMariaAlvesCruz_DISSERT.pdf: 5371387 bytes, checksum: f052cd71fa335b1d2bd2f6844d109e49 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-05T20:21:52Z (GMT) No. of bitstreams: 1 ErlannyMariaAlvesCruz_DISSERT.pdf: 5371387 bytes, checksum: f052cd71fa335b1d2bd2f6844d109e49 (MD5) / Made available in DSpace on 2017-01-05T20:21:52Z (GMT). No. of bitstreams: 1 ErlannyMariaAlvesCruz_DISSERT.pdf: 5371387 bytes, checksum: f052cd71fa335b1d2bd2f6844d109e49 (MD5) Previous issue date: 2016-02-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Esta Disserta??o de Mestrado compreende a an?lise estratigr?fica da Sequ?ncia Siluriana da Bacia do Parna?ba e est? vinculado ao Projeto de Pesquisa "Geologia e Sistemas Petrol?feros da Bacia Intracrat?nica do Parna?ba" financiado pela Chevron Brasil e UFRN/PPGG/FUNPEC. A Bacia do Parna?ba ? uma sin?clise paleozoica com ?rea de, aproximadamente, 600 mil km2 que situa-se no nordeste brasileiro e engloba parte dos estados do Maranh?o, Piau?, Tocantins, Par?, Cear? e Bahia. A an?lise estratigr?fica efetuada neste estudo foi dividida em duas etapas denominadas an?lise 1D e an?lise 2D. Na an?lise 1D foram utilizados dados de po?os, tais como, perfis de raios gama e litol?gicos, os quais possibilitaram o reconhecimento das unidades gen?ticas e superf?cies cronoestratigr?ficas da estratigrafia de sequ?ncias. Por sua vez, a an?lise 2D baseou-se na interpreta??o s?smica, a qual, aliada ? an?lise 1D permitiu a demarca??o das superf?cies estratigr?ficas e o entendimento do comportamento bidimensional das unidades gen?ticas identificadas. Nesta etapa tamb?m foi confeccionada uma se??o estratigr?fica com dire??o aproximada NW-SE que possibilitou um melhor entendimento sobre a hist?ria de sedimenta??o da se??o estudada. / This review presents a stratigraphic analysis of the Silurian Sequence of Parna?ba Basin and is related to the ?Geology and Petroleum Systems of the Parna?ba Intracratonic Basin? Research Project, funded by Chevron Brasil and UFRN/PPGG/FUNPEC. The Parna?ba Basin is a paleozoic sineclisis which encompasses an area of approximately 600,000 km? and is located in the Northeastern Region of Brazil, distributed throughout the states of Maranh?o, Piau?, Tocantins, Par?, Cear? e Bahia. The stratigraphic analysis implemented in this study was divided into two stages, referred to 1D and 2D analysis. In the 1D analysis well log data were used, such as gama ray and lithologic profiles, which provided the recognition of the genetic units and chronostratigraphic surfaces of sequence stratigraphy. On the other hand, the 2D analysis was based on the seismic interpretation, which along with the 1D analysis allowed the delimitation of the stratigraphic surfaces and the understanding of the bidimensional behavior of the genetic units identified .At this stage, a stratigraphic section with NW-SE direction, approximately, was created as well, providing a better understanding about the sedimentary evolution of the studied section.
3

An?lise estratigr?fica da sequ?ncia mesodevoniana-eocarbon?fera da Bacia do Parna?ba, nordeste do Brasil

Ferraz, Nadja Cruz 20 August 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-25T19:35:29Z No. of bitstreams: 1 NadjaCruzFerraz_DISSERT.pdf: 13420036 bytes, checksum: 48407aa7c5a58850e36ef79776b6b80c (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-29T20:32:49Z (GMT) No. of bitstreams: 1 NadjaCruzFerraz_DISSERT.pdf: 13420036 bytes, checksum: 48407aa7c5a58850e36ef79776b6b80c (MD5) / Made available in DSpace on 2016-07-29T20:32:49Z (GMT). No. of bitstreams: 1 NadjaCruzFerraz_DISSERT.pdf: 13420036 bytes, checksum: 48407aa7c5a58850e36ef79776b6b80c (MD5) Previous issue date: 2015-08-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A Sequ?ncia Mesodevoniana-Eocarbon?fera da Bacia do Parna?ba, litoestratigraficamente definida como Grupo Canind?, foi reinterpretada empregando-se o modelo b?sico da estratigrafia de sequ?ncias. Para tanto, foram analisados perfis litol?gicos e de raios gama de po?os e linhas s?smicas da regi?o central da bacia, elaborando-se a partir da? diagramas 1D, mapas de is?coras e uma se??o estratigr?fica. Como resultados deste trabalho, foram definidos dois ciclos deposicionais de segunda ordem, referidos como Sequ?ncia Deposicional 1 (SEQ1) e Sequ?ncia Deposicional 2 (SEQ2). A SEQ1, com cerca de 37 Ma, ? limitada abaixo pela Discord?ncia Eodevoniana e equivale ?s forma??es Itaim, Pimenteiras e Cabe?as. A SEQ1 se inicia com o Trato de Sistemas de N?vel Baixo, constitu?do por conjuntos de parassequ?ncias progradacionais em que a parte basal, predominantemente pel?tica, depositou-se em um contexto de prodelta sob influ?ncia de tempestades e a superior ? composta por arenitos de frente deltaica, tendo como limite superior a superf?cie regressiva m?xima. O Trato de Sistemas Transgressivo, depositado acima, ? caracterizado por conjuntos de parassequ?ncias retrogradacionais, compostos predominantemente por pelitos de plataforma rasa, depositados sob a??o de tempestades. A superf?cie transgressiva m?xima, limite superior deste trato, ? posicionada em um n?vel de folhelho cuja radiatividade no perfil de raios gama ? pr?xima a 150 API. O Trato de Sistemas de N?vel Alto apresenta conjuntos de parassequ?ncias progradacionais, compostos por pelitos e arenitos depositados em ambientes plataformal, fl?vio-estuarino e periglacial, tendo como limite superior a Discord?ncia Neodevoniana. A SEQ2, que se segue, compreende um intervalo de cerca de 15 Ma e equivale ? Forma??o Long?. A mesma foi depositada em ambiente plataformal, iniciando com o Trato de Sistemas de N?vel Baixo, caracterizado por um conjunto de parassequ?ncias progradacional, seguido do Trato de Sistemas Transgressivo, de car?ter retrogradacional. O limite superior deste trato corresponde ? superf?cie transgressiva m?xima ou ainda, a fus?o desta superf?cie com o limite de sequ?ncia, que constitui a Discord?ncia Eocarbon?fera, onde a se??o sobreposta foi erodida. Tal se??o, que corresponde ao Trato de Sistemas de N?vel Alto, ? restrita ?s por??es em que a eros?o que originou a Discord?ncia Eocarbon?fera foi menos efetiva, preservando os registros desta unidade. / The Middle Devonian-Early Carboniferous sequence of the Parna?ba Basin, lithostratigraphically defined as Canind? Group, has been reinterpreted using the basic model of sequence stratigraphy. Therefore, lithology and gamma ray well-logs and seismic lines of central portion of the basin were analyzed, producing up from there diagrams 1D, isochore maps and stratigraphic sections. As results of this study, were defined two depositional cycles of second order, referred as Depositional Sequence 1 (SEQ1) and the Depositional Sequence 2 (SEQ2). The SEQ1, with interval about 37 Ma, is limited below by Early Devonian Unconformity and is equivalent to the formations Itaim, Pimenteiras and Cabe?as. The SEQ2, which follows, comprises a range of about 15 Ma and is equivalent to the Long? Formation The SEQ1 starts with the lowstand systems tract, consisting of progradational parasequence set in the basal part, predominantly pelitic, deposited on a prodelta under influence of storms and the upper part consists in sandstones of deltaic front, with the maximum regressive surface on the upper limit. The transgressive systems tract, deposited above, is characterized by retrogradacional parasequence set composed of shallow shelf mudstones, deposited under storm conditions. The maximum flooding surface, upper limit of this tract, is positioned in a shale level whose radioactivity in gammaray well-log is close to 150 API. The highstand systems tract presents progradational parasequence set, comprising mudstones and sandstones deposited in shelf, fluvial-estuarine or deltaic and periglacial environments, with the upper limit the Late Devonian Unconformity. The SEQ2 was deposited in shelf environment, starting with the lowstand systems tract, that is characterized by a progradational parasequence set, followed by the transgressive systems tract, with retrogradational character. The upper limit of the tract corresponding to the fusion between maximum flooding surface with the upper limit of this sequence, which is the Early Carboniferous Unconformity, where the overlapping section was eroded. This section, which corresponds the highstand systems tract is restricted to portions at which the erosion that generate the Early-Carboniferous Unconformity was less effective, preserving the records of this unit.
4

Caracteriza??o de reservat?rios silicicl?sticos neoaptianos: um estudo do membro carm?polis no campo de Camorim, sub-bacia de Sergipe, Brasil

Lira, Filipe Silva 27 June 2013 (has links)
Made available in DSpace on 2015-03-13T17:08:38Z (GMT). No. of bitstreams: 1 FilipeSL_DISSERT.pdf: 18861623 bytes, checksum: dec06565f69ab3657111750b25f78441 (MD5) Previous issue date: 2013-06-27 / The Camorim Oilfield, discovered in 1970 in the shallow water domain of the Sergipe Sub-basin, produces hydrocarbons from the Carm?polis Member of the Muribeca Formation, the main reservoir interval, interpreted as siliciclastics deposited in an alluvial-fluvial-deltaic context during a late rifting phase of Neoaptian age, in the Sergipe-Alagoas Basin. The structural setting of the field defines different production blocks, being associated to the evolution of the Atalaia High during the rift stage and subsequent reactivations, encompassing NE-SW trending major normal faults and NWEW trending secondary faults. The complexity of this field is related to the strong facies variation due to the interaction between continental and coastal depositional environments, coupled with strata juxtaposition along fault blocks. This study aims to geologically characterize its reservoirs, to provide new insights to well drilling locations in order to increase the recovery factor of the field. Facies analysis based on drill cores and geophysical logs and the 3D interpretation of a seismic volume, provide a high resolution stratigraphic analysis approach to be applied in this geodynamic transitional context between the rift and drift evolutionary stages of the basin. The objective was to define spatial and time relations between production zones and the preferential directions of fluid flow, using isochore maps that represent the external geometry of the deposits and facies distribution maps to characterize the internal heterogeneities of these intervals, identified in a 4th order stratigraphic zoning. This work methodology, integrated in a 3D geological modelling process, will help to optimize well drilling and hydrocarbons production. This methodology may be applied in other reservoirs in tectonic and depositional contexts similar to the one observed at Camorim, for example, the oil fields in the Aracaju High, Sergipe Sub-basin, which together represent the largest volume of oil in place in onshore Brazilian basins / O Campo de Camorim, descoberto em 1970 na por??o de ?guas rasas da Subbacia de Sergipe, produz hidrocarbonetos do Membro Carm?polis/Forma??o Muribeca, principal intervalo reservat?rio, interpretado como silicicl?sticos depositados em um contexto al?vio-fl?vio-deltaico na fase tardia do rifteamento da Bacia Sergipe-Alagoas, Neoaptiano. O arcabou?o estrutural, que subdivide o campo em blocos produtores, est? associado ? evolu??o do Alto de Atalaia durante a fase rifte e reativa??es posteriores, apresentando falhas normais principais de dire??o NE-SW e falhas secund?rias de dire??es NW-SE e E-W. A complexidade do campo est? ligada ? intensa varia??o faciol?gica, resultante da intera??o entre os ambientes deposicionais continentais e costeiros, e a justaposi??o dos estratos associada ? evolu??o estrutural. Este trabalho tem como objetivo a caracteriza??o geol?gica dos reservat?rios para dar subs?dios ?s novas perfura??es de po?os destinados a aumentar o fator de recupera??o do campo. Deste modo, a partir da an?lise faciol?gica realizada em testemunhos e perfis geof?sicos, em conjunto com a interpreta??o do volume s?smico 3D, prop?e-se uma metodologia que se baseia na an?lise estratigr?fica de alta resolu??o, aplicada em um contexto geodin?mico transicional entre os est?gios rifte e drifte de evolu??o da bacia, capaz de determinar as rela??es espaciais e temporais das zonas produtoras e as dire??es preferenciais do fluxo de fluidos, empregando para este fim, mapas de is?coras que representam a geometria externa, e mapas de distribui??o de f?cies para as heterogeneidades internas destes intervalos identificados em um zoneamento estratigr?fico de 4? ordem. Esta metodologia de trabalho, integrada em um processo de modelagem geol?gica 3D, vai ser utilizada para estabelecer a geometria da malha de po?os injetores/produtores do intervalo de interesse e pode ser aplicada em outros reservat?rios cujo contexto tect?nico-deposicional seja semelhante ao observado em Camorim, caso dos campos localizados no Alto de Aracaju, Sub-bacia de Sergipe, que juntos comp?em o maior volume de ?leo in place na por??o terrestre das bacias brasileiras
5

Estratigrafia de sequ?ncias do intervalo aptiano ao albiano na Bacia do Araripe, NE do Brasil

Rojas, Fabio Enrique Malagon 27 February 2009 (has links)
Made available in DSpace on 2015-03-13T17:08:18Z (GMT). No. of bitstreams: 1 FabioEMR_Capa_ate_Cap3.pdf: 2956379 bytes, checksum: e1a356dd8141f0ac9ce3d477be9710dc (MD5) Previous issue date: 2009-02-27 / This study has as a main objective to make a detailed stratigraphic analysis of the Aptian-Albian interval in the east part of Araripe Basin, NE of Brazil which correspond, litostratigraphically, to Rio Da Batateira, Crato, Ipubi and Romualdo formations. The stratigraphic analysis was based on three different stages, the 1D, 2D and 3D analysis; these ones were adapted to the sequence stratigraphy concepts in order to create a chronostratigraphic framework for the study area within the basin. The database used in the present study contains field and well information, wells that belong to Santana Project, carried out by the Minist?rio de Minas e Energia- DNPM- CPRM from 1977 to 1978. The analysis 1D, which was done separately for each well and outcrop allowed the recognition of 13 sedimentary facies, mainly divided based on predominant litologies and sedimentary structures. Such facies are lithologically represented by pebble, sandstones, claystones, margas and evaporates; these facies are associated in order to characterize different depositional systems, that integrate from the continental environment (fluvial system and lacustre), paralic system (delta system and lagunar) to the marine environment (shelfenvironment). The first one, the fluvial system was divided into two subtypes: meandering fluvial system, characterized by fill channel and floodplain deposits; the facies of this system are associated vertically according to the textural thinning upward cycles (dirting-up trend pattern in well logs). Lacustrine environment is mainly related with the lithotypes of the Crato Formation, it shows a good distribution within the basin, been composed by green claystone deposits and calcareous laminated. Deltaic System represented by prodelta and delta front deposits which coarsening upward tendency. Lagunar system is characterised by the presence of anhydrite and gypsum deposits besides the black claystone deposits with vegetal fragments which do not contain a fauna typically marine. The marine platform system is composed by successions of black and gray claystone with fossiliferous fauna of Dinoflagellates (Spiniferites Mantell, Subtilisphaera Jain e Subtilisphaera Millipied genre) typical of this kind of depositional system. The sedimentary facies described are vertically arranged in cycles with progradational patterns which form textural coersening upward cycles and retrogradational, represented by textural thinning dowward cycles. Based in these cycles, in their stack pattern and the vertical change between these patterns, the systems tracks and the depositional sequences were recognized. The Low System Track (LST) and High System Track (HST) are composed by cycles with progradational stack pattern, whereas the Trangessive System Track (TST) is composed by retrogradational stack pattern cycles. The 2D stratigraphic analysis was done through the carrying out of two stratigraphic sections. For the selection of the datum the deepest maximum flooding surface was chosen, inside the Sequence 1, the execution of these sections allowed to understand the behaviour of six depositional systems along the study area, which were interpreted as cycles of second order or supercycles (cycles between 3 and 10 Ma), according to the Vail, et al (1977) classification. The Sequence 1, the oldest of the six identified is composed by the low, transgressive and high systems tracks. The first two system tracks are formed exclusively by fluvial deposits of the Rio da Batateira Formation whereas the third one includes deltaic and lacustrine deposits of the Crato Formation. The sequences 2 and 3 are formed by the transgressive systems tracks (lake spreading phase) and the highstand system track (lake backward phase). The TST of these sequences are formed by lacustrine deposits whereas HST contains deltaic deposits, indicating high rates of sedimentary supply at the time of it s deposition. The sequence 4 is composed by LST, TST and HST, The TST4 shows a significant fall of the lake base level, this track was developed in conditions of low relation between the creation rate of space of accommodation and the sedimentary influx. The TST4 marks the third phase of expansion of the lacustrine system in the section after the basin?s rift, the lacustrine system established in the previous track starts a backward phase in conditions that the sedimentary supply rate exceeds the creation rate of space accommodation. The sequence 5 was developed in two different phases, the first one is related with the latest expansion stage of the lake, (TST5), the basal track of this sequence. In this phase the base level of the lake rose considerably. The second phase (related to the TST5) indicates the end of the lacustrine domain in the Araripe Basin and the change to lagunar system ant tidal flat, with great portions in the supratidal. These systems were formed by restricted lagoons, with shallow level of water and with intermittent connections with the sea. This, was the phase when the Araripe Basin recorded the most several arid conditions of the whole interval studied, Aptian Albian, conditions that allow the formation of evaporitic deposits. The sequence 6 began its deposition after a significant fall of the sea (LST6). The sequence 6 is without any doubtlessly, the sequence that has deposits that prove the effective entrance of the sea into the Araripe Basin. The TST6, end of this sequence, represents the moment which the sea reaches its maximum level during the Aptian Albian time. The stratigraphic analysis of the Aptian Albian interval made possible the understanding that the main control in the development of the depositional sequences recognized in the Araripe Basin were the variations of the local base level, which are controlled itself by the climate changes / O presente trabalho tem como objetivo principal realizar uma an?lise estratigr?fica detalhada do intervalo Aptiano ao Albiano na parte leste da Bacia do Araripe, NE do Brasil, o qual corresponde, litoestratigraficamente, ?s forma??es Rio da Batateira, Crato, Ipub? e Romualdo. A an?lise estratigr?fica envolveu tr?s etapas distintas, a an?lise 1D, 2D e 3D, nas quais foram adaptados os conceitos da estratigrafia de seq??ncias visando elaborar um arcabou?o de car?ter cronoestratigr?fico para a por??o estudada da bacia. Tal estudo contou com uma base de dados integrada por informa??o de campo e de po?os pertencentes ao projeto Santana, realizado pelo Minist?rio de Minas e Energia- DNPM- CPRM nos anos de 1977 e 1978. A an?lise 1D, por meio da an?lise individual de cada afloramento e po?o, permitiu o reconhecimento de 13 f?cies sedimentares, individualizadas com base principalmente nas litologias predominantes e nas estruturas sedimentares. Tais f?cies s?o representadas litologicamente por conglomerados, arenitos, pelitos, calc?rios, margas e evaporitos. As mesmas se associam de forma a caracterizar diferentes sistemas deposicionais, que integram desde o ambiente continental (sistemas fluvial e lacustre), ambiente par?lico (sistemas deltaico e lagunar) at? o ambiente marinho (sistema plataformal). O primeiro deles, o sistema fluvial, foi dividido em dois sub-tipos: o sistema fluvial meandrante, caracterizado por dep?sitos de preenchimento de canal e dep?sitos de plan?cie de inunda??o, e o sistema fluvial entrela?ado formado principalmente por dep?sitos de preenchimento de canal; as f?cies deste sistema se associam verticalmente segundo ciclos de afinamento textural para o topo (padr?o em sino nos perfis geof?sicos). O sistema lacustre, relacionado principalmente aos lit?tipos da Forma??o Crato, apresenta uma boa distribui??o na bacia, sendo composto por dep?sitos de pelitos verdes e calc?rios laminados. O sistema deltaico, representado por dep?sitos de prodelta e de frente deltaica, os quais se disp?em verticalmente em ciclos com granocresc?ncia para o topo (padr?o em sino invertido nos perfis geof?sicos). O sistema lagunar caracteriza-se pela presen?a de dep?sitos de anidrita e gipsita, al?m dos dep?sitos de pelitos negros com restos vegetais, os quais n?o cont?m uma fauna tipicamente marinha. O sistema de plataforma marinha ? composto por sucess?es de pelitos pretos e cinza com faunas fossiliferas de Dinoflagelados (g?neros Spiniferites Mantell, Subtilisphaera Jain e Subtilisphaera Millipied), t?picas de este tipo de sistema deposicional. As f?cies sedimentares descritas se arranjam verticalmente de forma a compor ciclos com padr?es de empilhamento progradacional, os quais formam ciclos com engrossamento textural para o topo, e retrogradacional, representados por ciclos com afinamento textural para o topo. Com base nestes ciclos, em seus padr?es de empilhamento e na mudan?a verticais entre estes padr?es, foram reconhecidos os tratos de sistemas e as seq??ncias deposicionais. Os tratos de sistemas de N?vel Baixo e o de N?vel Alto s?o compostos por ciclos com padr?o de empilhamento progradacional; o Trato de Sistemas Transgressivo, por sua vez, ? formado por ciclos com padr?o de empilhamento retrogradacional. A an?lise estratigr?fica 2D foi elaborada por meio da realiza??o de duas se??es estratigr?ficas. Para a escolha do datum foi privilegiada a superf?cie de m?xima inunda??o mais basal, interna ? Seq??ncia 1. A elabora??o destas se??es possibilitou compreender o comportamento de seis seq??ncias deposicionais ao longo da ?rea de estudo, as quais foram interpretadas como ciclos de segunda ordem ou superciclos (ciclos com dura??es entre 3 e 10 Ma), segundo a classifica??o de Vail, et al (1977). A Seq??ncia 1, mais antiga das seis seq??ncias identificadas, ? composta pelos tratos de sistemas de N?vel Baixo, Transgressivo e de N?vel Alto. Os dois primeiros tratos s?o formados exclusivamente pelos dep?sitos fluviais da Forma??o Rio da Batateira, ao passo que o terceiro inclui dep?sitos deltaicos e lacustres da Forma??o Crato. As seq??ncias 2 e 3 s?o formadas pelos tratos de sistemas Transgressivo (TST; fase de expans?o do lago) e de N?vel Alto (TSNA; fase retra??o do lago). Os TST s destas seq??ncias s?o formados por dep?sitos lacustres, ao passo que os TSNA s cont?m dep?sitos deltaicos, indicando assim condi??es de alta taxa de suprimento sedimentar na ?poca da deposi??o deste. A seq??ncia 4 ? formada pelos tratos de sistemas de N?vel Baixo (TSNA), Transgressivo e de N?vel Alto. O TSNB registra uma queda importante do n?vel base do lago; este trato se desenvolveu em condi??es de baixa raz?o entre a taxa de cria??o de espa?o de acomoda??o e a taxa de influxo sedimentar. O TST marca a terceira fase de expans?o do sistema lacustre na se??o p?s rifte da bacia; o sistema lacustre implantado no trato anterior inicia uma fase de retra??o em condi??es em que a taxa de aporte sedimentar passa a suplantar a de cria??o de espa?o de acomoda??o. A seq??ncia 5 desenvolveu-se em duas fases distintas. A primeira relaciona-se com a ?ltima etapa de expans?o do lago, (TST), trato basal desta seq??ncia. Nesta fase, o n?vel base do lago subiu consideravelmente. A segunda fase, relacionada ao TSNA), indica o final do dom?nio lacustre na Bacia do Araripe e a mudan?a para sistemas lagunares e de plan?cie de mar?, com grande desenvolvimento das por??es de supramar?. Estes sistemas eram formados por lagunas restritas, com l?mina de ?gua rasa, e com conex?o intermitente com o mar. Esta foi a fase em que a Bacia do Araripe registrou as mais severas condi??es de aridez de todo intervalo estudado, Aptiano ao Albiano, condi??es estas que propiciaram a forma??o de dep?sitos evapor?ticos. A seq??ncia 6 iniciou sua deposi??o ap?s uma queda significativa do incipiente mar (TSNB). Esta seq??ncia ?, indubitavelmente, a que cont?m os dep?sitos que comprovam a efetiva entrada do mar na Bacia do Araripe. O TST, trato final desta seq??ncia, representa o momento em que o n?vel do mar atingiu o seu m?ximo durante todo o intervalo Aptiano ao Albiano. A an?lise estratigr?fica do intervalo Aptiano ao Albiano permitiu compreender que o controle principal no desenvolvimento das seq??ncias deposicionais reconhecidas na Bacia do Araripe foram ?s varia??es do n?vel de base local, as quais s?o controladas, por sua vez, pelas mudan?as clim?ticas

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