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Redescrição da anatomia craniana e pós-craniana do fóssil Bauruemys elegans (Suárez, 1969) do Cretáceo Superior da Bacia Bauru e seu posicionamento filogenético dentro da Epifamília Podocnemidinura (Testudines, Pelomedusoides). / Redescription of cranial and post-cranial anatomy of Bauruemys elegans from Upper Cretaceous of Bauru Basin and its phylogenetical position within Epifamily Podocnemidinura (Pelurodira, Pelomedusoides)William Matiazzi 15 August 2007 (has links)
No presente trabalho o gênero fóssil Bauruemys elegans é redescrito. Sua anatomia craniana e pós-craniana foi analisada em detalhes com base em novos exemplares coletados deste fóssil. Bauruemys elegans é um quelônio do Cretáceo Superior da Bacia Bauru, encontrado no Município de Pirapozinho, interior do estado de São Paulo e descrito originalmente por Suárez em 1969 como Podocnemis elegans. Os materiais analisados foram comparados com a osteologia de representantes atuais dos clados Chelidae, Pelomedusidae e Podocnemididae, bem como com descrições de outros táxons disponíveis na literatura. As relações filogenéticas de Bauruemys elegans dentro do clado Podocnemidinura foram analisadas através da análise de parcimônia envolvendo 19 táxons e 56 caracteres. Nesta análise Bauruemys elegans constitui, de fato, um gênero distinto entre os podocnemidídeos, corroborando propostas já descritas na literatura. A análise também revelou que, através dos caracteres osteológicos, Bauruemys elegans possui afinidades filogenéticas próximas aos podocnemidídeos atuais, posicionando-se como grupo-irmão do clado formado pelo fóssil Cambaremys langertoni e pela Família Podocnemididae. / In this study, the fossil Bauruemys elegans is redescribed. Its cranial and postcranial anatomy was analysed in detail based on new specimens collected. Bauruemys elegans is a chelonian from Upper Cretaceous of the Bauru Basin founded in the municipality of Pirapozinho, São Paulo state and was originally described by Suarez (1969) as Podocnemis elegans. The specimens analysed was compared with some extant representatives of Chelidae, Pelomedusidae and Podocnemididae families and descriptions avaliable on the literature. The phylogenetic affinities of the Bauruemys elegans within Podocnemidinura was evaluated through a parsimony analysis envolving 19 taxa and 56 characters. The results of phylogenetic analysis shows that Bauruemys elegans is, in fact, a distinct genus within the clade Podocnemididae. This corroborated anterior hypothesis proposed. Adittionally, this analysis using osteological characters, indicate Bauruemys elegans as the sister group of Cambaremys langertoni and Podocnemididae.
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Brachiopoda a polychaeta v tafocenózách české křídové pánve / Brachiopoda and polychaeta in Taphocenoses of the Bohemian Cretaceous BasisSklenář, Jan January 2013 (has links)
The sesile suspension feeders of Brachiopoda and Polychaeta phyla are relatively well represented in the Bohemian Cretaceous Basin (BCB), and show significant diversity. All three subphyla of Brachiopoda (Linguliformea, Craniiformea and Rhynchonelliformea) are present in the fossil record of the sedimentary basin infill; from Polychaeta, there has hith- erto been evidence of only the Canalipalpata subclass members that created solid, usually carbonatic tubes. In both abundancy and diversity, the most richest associations of fossil brachiopods and polychaets occure in near-shore facies of the Cenomanian to the Lower Turonian, and hemipelagic facies of the Late Turonian age. Prior research, as shows the literature survey given by the author, has been focused mainly on representatives of both groups of near-shore facies origin. The aim of this thesis is to fill in the existing gaps in our understanding of these groups within the BCB. This objective is accomplished in the form of a series of studies (Sklenář & Simon 2009, Vodrážka & al. 2009, Sklenář & al., in press) elaborating the following topics in detail: (A) taxonomy, distribution, morphology, variabil- ity, evolutionary relationships and stratigraphic significance of cancellothyrid brachiopod Gyrosoria abundant in the Middle and particularly in...
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Evolution tectono-sédimentaire d’une marge obductée : l’exemple de la Nouvelle-Calédonie et de son domaine offshore (Sud-Ouest Pacifique) / Tectono-sedimentary evolution of an obducted margin : the example of New Caledonia and its offshore domain (South West Pacific)Bordenave, Aurélien 05 July 2019 (has links)
La marge active Est Gondwanienne s'est développée dans un contexte de subduction de type andine entre le Permien et le Crétacé inférieur. Suite à une période de rifting régional au Crétacé supérieur, qui précède l'océanisation de la Mer de Tasman, le continent Zealandia se détache du Gondwana. A l'Eocène, un événement tectonique majeur entraine l'obduction de matériel mantellique sur la marge Nord-Est du continent Zealandia, qui affleure aujourd'hui en Nouvelle-Calédonie (NC). L’enregistrement de ces événements tectoniques est accessible dans les bassins Ouest calédoniens dans lesquels d’épaisses séries sédimentaires se sont déposées. La longue période de subduction Phanérozoïque est principalement enregistrée par le dépôt de séries de turbidites volcanoclastiques (« grauwackes ») tandis que les périodes de rifting et de post-rift sont associées au dépôt de formations fluvio-deltaïques passant latéralement à des dépôts turbiditiques. La période pré/ syn-obduction, encore mal comprise et complexe, s’enregistre par une épaisse série gravitaire syn-tectonique (« Flysch ») sur laquelle reposent des formations mixtes silici-carbonatées en contexte récifal et lagunaire à terre, et turbiditique en mer. Ces séries sédimentaires sont aujourd’hui relativement bien cartographiées et identifiées à terre, mais leur étude détaillée d’un point vue sédimentologique fait toujours défaut. L’analyse de la carotte du puits onshore Cadart-1 qui échantillonne 1950 m des séries syn-rift à syn-obduction et des nombreux affleurements de la côte Ouest de la Grande Terre permettra d’apporter de nouveaux éléments sur les faciès, les géométries et les architectures de ces différentes séries. Aussi, une approche terre-mer est proposée en s’appuyant sur la nouvelle carotte IODP 371 U1507 et sur le nouveau jeu de données sismiques de la campagne TECTA acquis dans le Bassin de Nouvelle-Calédonie. L’objectif principal est d’améliorer la connaissance de l’histoire tectonique et sédimentaire de la Nouvelle-Calédonie à partir des enregistrements sédimentaires des bassins ouest-calédoniens, d’en déduire leur évolution paléogéographique en lien avec l’histoire géodynamique régionale. Sur un plan plus fondamental cette étude apportera des nouveaux éléments permettant de mieux comprendre les mécanismes de l’obduction. D’un point de vue appliqué, ce travail permettra également d’apporter des informations essentielles sur les potentielles roches mères, réservoirs et couvertures du système pétrolier des bassins de la Nouvelle-Calédonie. / From Permian to Early Cretaceous the eastern Gondwana margin was an Andine subduction context. Late Cretaceous widespread regional rifting affects this region and precedes Cretaceous to Eocene seafloor spreading of the Tasman Sea, leading to the isolation of the Zealandia continent. During the Eocene, a major tectonic event affects the entire region and leads to the obduction of mantellic material on the northeastern margin of Zealandia, which presently outcrops in New-Caledonia. The stratigraphic records of these tectonics events are accessible within the western New-Caledonian basins, in which very thick sedimentary series were deposited and are now visible through onland outcrops. The Phanerozoic eastern Gondwana subduction episode is recorded by volcanoclastic turbidites whereas rifting and post-rift phases are associated with fluvial-estuarian deposits capped by deeper deposits. The complex pre to syn-obduction phase is recorded by a very thick syntectonic gravity flow unit (“Flysch”), composed of turbidites originating from various siliciclastic and carbanoceous sources. These sedimentary series are well mapped and identified in New-Caledonia, but a detailed sedimentological description and interpretation is still lacking. Core descriptions from the CADART well which recovered 1930 meter of “flysch” series, combined with outcrop descriptions should bring new insight onto the sedimentary facies, geometries and stratigraphic architecture of these series. Following this, we focused on newly acquired data in the New Caledonian Basin, including new multichannel seismic data acquired during the TECTA cruise as well as new drilling data performed in 2017 during IODP Expedition 371. The main objective of this study is to improve the knowledge of the tectonic history of New Caledonia, from these sedimentary records. On a fundamental aspect, this study will allow to better understand the obduction mechanisms. In addition, this study should provide new information on the potential petroleum system of New-Caledonian basins.
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Sedimentology of the Wapiabi-Belly River Transition and the Belly River Formation (Upper Cretaceous) near Ghost Dam, AlbertaHaywick, Douglas Wayne 04 1900 (has links)
<p> The Wapiabi-Belly River transition and the Belly River Formation was studied in detail in seven sections in the Ghost Dam spillway, near Ghost Dam,Alberta. Units in the lowest portion of the outcrop (Wapiabi) are characterized by sandy mudstones, often coarsening upwards. The mudstones are overlain by storm generated, hummocky cross-stratified sandstones and beach deposits. The vertical sequence represents a shallowing trend. </p> <p> Above the beach deposits lie sandstone and interbedded mudstone-sandstone units (Belly River) deposited in a meandering river environment. Sandstones thicker than approximately two metres were deposited as point bars, show sedimentary structures representative of channels and often pinch out, or laterally interfinger with mudstone. Interbedded mudstone-sandstone units were formed during flood stances. These overbank deposits are classified as either proximal or distal components of the meandering river system. </p> <p> Several marine trace fossils, (Macaronichnus segregatis, Skolithos, Planolites, Chondrites, Teichichnus, and Ophiomorpha nodasa), found in the Belly River rocks suggest a minor marine influence on the river system. </p> <p> The river system is inferred to have been moderately to highly sinuous and comparable in discharge to the Humber and Credit Rivers (Ontario). </p> <p> Petrographic studies show that point bar sandstones are often characterized by fining upward trends and an upward increase in the proportion of carbonate cement. </p> <p> Distal overbank deposits are normally overlain by proximal overbank deposits which inturn are overlain by either point bars or distal overbank deposits. Point bar deposits may be overlain by either proximal or distal overbank. </p> / Thesis / Bachelor of Science (BSc)
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Oceanic Anoxia Event 2 (~94 Ma) in the U.S. Western Interior Sea: High Resolution Foraminiferal Record of the Development of Anoxia in a Shallow Epicontinental SeaParker, Amanda L 23 March 2016 (has links) (PDF)
The Upper Cretaceous Tropic Shale of southern Utah captures critical oceanographic changes that occurred during Oceanic Anoxic Event 2 (OAE 2) and the transgression of the Greenhorn Sea. We investigated the response of planktic and benthic foraminifera in a shallow (<100 >m) marine environment stressed by the onset of OAE 2 during the Cenomanian-Turonian boundary (CTB; 93.9 Ma) to determine the oceanographic mechanisms controlling the observed turnovers in the foraminiferal record. This study is based on high-resolution quantitative foraminifera counts and isotope paleoecology (d18O and d13C) from a 40-m outcrop. The OAE 2 interval is identified by a distinctive d13Corg signature and by correlation of bentonites and limestones across the seaway.
Results of assemblage analyses indicate discrete intervals of environmental perturbations across the CTB interval. At the onset of OAE 2, surface waters were dominated by planktic Guembelitra cenomana with minor species of Heterohelix. Benthic abundances increase and were initially dominated by oxygen tolerant infaunal Neobulimina albertensis. Epifaunal Gavelinella dakotaensis briefly proliferated during the core of the OAE 2 and coinciding with the planktic “Heterohelix shift” and increasing accumulation of organic matter. The peak of OAE 2 at ~17 m is marked by a rapid shift to infaunal Neobulimina dominance. We suspect incursion of oxygen-poor Tethyan intermediate waters with peak transgression during the early Turonian, coupled with high productivity in surface waters resulted in the rapid depletion of benthic oxygen. The foraminiferal record reveals strong cyclicity in planktic/benthic ratio resembling parasequences that correlate to the GSSP in central Colorado.
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Flora fóssil do pontal Rip, Ilha Nelson, Península Antártica: taxonomia e contexto geológicoBastos, Bibiana Liguori 08 1900 (has links)
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Previous issue date: 2012-08 / CNPQ – Conselho Nacional de Desenvolvimento Científico e Tecnológico / Fósseis de plantas são comuns na Península Antártica e têm sido encontrados não apenas em áreas orientais, correspondentes aos ambientes de retro-arco, mas também na Terra de Graham e no arquipélago das Shetland do Sul, que representam respectivamente, o contexto de arco e ante-arco. Na ilha Nelson, que faz parte do arquipélago das Shetland do Sul, o registro fossilífero mostra-se profundamente ligado aos processos vulcânicos que marcaram sua história, inicialmente afetada pelos eventos mesozóicos de subducção do Pacífico e posteriormente pela construção de um arco de ilhas. A macro e microflora encontradas em um depósito piroclástico retrabalhado no nível superior do pontal Rip, a noroeste da Ilha Nelson, são aqui apresentadas pela primeira vez. Na macroflora dominam folhas muito fragmentadas de Nothofagus e de formas primitivas de angiospermas, relacionadas às famílias Lauraceae, Anacardiaceae e Melastomataceae. Escassas pínulas de pteridófitas e um único ramo de conífera também compõem esta assembleia. Entre os palinomorfos, as pteridófitas são o principal componente, seguidas por grãos de pólen de gimnospermas. A presença de grãos relacionados à Nothofagus é atestada por tipos ancestrais e modernos (e.g. Nothofagidites cf. endurus, N. cf. kaitangataensis e N. cf. brachyspinulosus). Grãos de Classopollis, em associação com Nothofagidites cf. endurus e N. cf. kaitangataensis, sugerem uma idade neocretácica para este depósito. Em relação à correlação estratigráfica, a composição da macroflora também mostrou maior identidade com aquelas presentes em outras exposições na ilha King George, especialmente, com assembléias atribuídas ao Campaniano médio (e.g. pontal Half Three, pontal Price e monte Zamek). Em termos paleofitogeográficos, foi possível observar o domínio das angiospermas relacionadas às formas decíduas e primitivas de Nothofagus, muitas das quais são similares a espécies modernas que crescem em áreas ao sul da América do Sul. Deste modo, baseando-se no domínio de folhas microfílicas e na presença de folhas e grãos de pólen relacionados à Nothofagus, pode-se sugerir uma condição de clima temperado úmido para a Península durante a deposição do nível estudado. Por fim, deve-se ressaltar que as pteridófitas (famílias Blechnaceae e Hymenophyllaceae), a cupressácea do gênero Papuacedrus e alguns dos morfotipos associados à Nothofagus aqui descritos, indicam que ainda existiam terras contínuas entre a Península Antártica e a Australásia durante o final do Cretáceo. / Plant fossils are common in the Antarctic Peninsula and have been found not only in the eastern areas that correspond to the back arc deposition environments, but also in the Graham Land and the South Shetland archipelago, which represent the arc and fore arc contexts, respectively. In the Nelson Island, part of the South Shetland archipelago, the fóssil record is deeply linked to the volcanic processes that marks its geological history, initially affected by the Mesozoic subduccion events and after by the construction of an island arc. The macro and microflora found in a reworked pyroclastic deposit from the upper part of Rip Point outcrop, in northwestern Nelson Island, are herein presented for the first time. The macroflora is dominated by very fragmented leaves of Nothofagus and primitive forms of angiosperms, related to the families Lauraceae, Anacardiaceae and Melastomataceae. Rare pinnules of Pteridophyta and a sole and partial conifer shoot also compound this assemblage. Amongst the palynomorphs, the Pteridophyta are a main component, follow by pollen grains of gymnosperms. The presence of grains related to Nothofagus is represented by ancestral and modern types (e.g. Nothofagidites cf. endurus, N. cf. kaitangataensis and N. cf. brachyspinulosus). The Classopollis grains, in association with Nothofagidites cf. endurus, N. cf. kaitangataensis, suggested a Late Cretaceous age to this deposit. In relation to stratigraphic correlation, the composition of macroflora showed also a greatest identity with ones recorded in other exposures found in the King George Island, specially, with assemblages attributed to the middle Campanian (e.g. Half Three point, Price point and Zamek Hill). In terms of paleophytogeography, it was possible observe the domain of angiosperms related to a deciduous and primitive leaves of Nothofagus, similar to many of modern species that live in southern South America. In this way, it is suggested that the Antarctic Peninsula was under a humid temperate climatic condition during the deposition time of study interval, based on the domain of microfilic leaves and the presence of leaves and pollen grains related to Nothofagus. Finally, it should be highlighted that the pteridophytes (families Blechnaceae e Hymenophyllaceae), the cupressacea of genus Papuacedrus and the few morphotypes associated to Nothofagus described here, indicated the existence of a land connection between the Antarctic Peninsula and Australasia during the end of Cretaceous.
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Stratigraphy of the Lower Tertiary and Upper Cretaceous (?) Continental Strata in the Canyon Range, Juab County, UtahStolle, James M. 01 January 1978 (has links)
The Canyon Range Formation (informal new name), formerly mapped as the Indianola Group within the Canyon Range, is divisible into two distinct, mappable units, A and B. Unit A is nearly all conglomerate strata, and conglomerate texture and sedimentary structures suggest an alluvial fan depositional environment. Precambrian and basal Cambrian quartzite clasts represent the erosional debris from the allochthonous Canyon Range thrust. Unit B is composed of interbedded fluvial sandstone and conglomerates with lacustrine limestones, commonly micritic and/or oncolitic. Conglomerate clasts indicate a Paleozoic carbonate provenance. Unit A, previously mapped as the Indianola, underlies Unit B and correlates with the Price River-lower North Horn Formations of the Pavant Range and Long Ridge. Marginal paleontologic and stratigraphic indicators suggest Unit B to be equivalent to the Paleocene-Eocene North Horn and Flagstaff Formations rather than the Cretaceous Indianola Group. Stratigraphic and structural relationships indicate the last major phase of "Sevier" thrusting ended by Price River (?) time.
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Planktonic Foraminiferal Biostratigraphy, Sequence Stratigraphy And Foraminiferal Response To Sedimentary Cyclicity In The Upper Cretaceous-paleocene Of The Haymana Basin (central Anatolia, Turkey)Amirov, Elnur Fikret 01 November 2008 (has links) (PDF)
The aim of this study is to establish the planktonic foraminiferal biozonation, to construct the sequence stratigraphical framework and to determine the foraminiferal response to sedimentary cyclicity in the sedimentary sequence spanning Upper Cretaceous-Paleocene in the Haymana basin (Central Anatolia, Turkey).
In order to achieve this study, the stratigraphic section was measured from sedimentary sequence of the Haymana, Beyobasi and YeSilyurt formations. The sedimentary sequence is mainly characterized by flyschoidal sequence that is composed of alternating of siliciclastic and carbonate units.
On the account of the detailed taxonomic study of planktonic foraminifers, the biostratigraphic framework was established for the Maastrichtian-Paleocene interval. The biozonation includes 7 zones / Pseudoguembelina hariaensis, P& / #945 / , P1, P2, P3, P4 and P5 zones. The Cretaceous-Paleogene (K/P) boundary was delinated between the samples HEA-105 and 106.
In order to construct the sequence-stratigraphical framework, the A, B, C and D-type meter-scale cycles were identified. Based on the stacking patterns of them, six depositional sequences, six third and two second order cycles were determined. Third order cycles coincide with the Global Sea Level Change Curve.
On the account of the conducted petrographic analysis sandstone, mudstone, marl, limestone and muddy-limestone lithofacies were recorded in the studied samples. In order to demostrate the response of foraminifers to cyclicity, quantitative analysis has been carried out by counting the individuals of planktonic, benthonic foraminifers and ostracods. The best response to sedimentary cyclicity was revealed from planktonic foraminifers. The average abundance of planktonic foraminifers increases in the transgressive systems tract and decreases in the highstand systems tract.
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Proveniência dos arenitos-reservatório de água profunda do Campo de Jubarte, Bacia de Campos, margem continental brasileiraFontanelli, Paola de Rossi January 2007 (has links)
A utilização de técnicas integradas de análise de proveniência sedimentar, incluindo a petrografia quantitativa utilizando o método Gazzi-Dickinson, a análise convencional de minerais pesados, a análise da composição química de granadas (análise varietal) e a geocronologia U-Pb (LAM-ICPMS-MC) em zircão, permitiram a identificação das áreas-fonte e o padrão de suprimento sedimentar dos arenitos de água profunda maastrichtianos que constituem os reservatórios do Campo de Jubarte, Bacia de Campos. Os arenitos são pobremente selecionados, com grãos sub-angulares a angulares, denotando rápido transporte. Apresentam composição original rica em feldspatos (arcósios sensu Folk, 1968) e pobre em fragmentos líticos de textura fina, proveniente de terrenos soerguidos de embasamento (sensu Dickinson, 1985). As assembléias de minerais pesados indicam proveniência a partir de rochas metamórficas de alto e médio grau, derivadas de metapelitos aluminosos metamorfisados em altas temperaturas e pressões baixas a médias, de granitos e subordinadamente de rochas máficas (metabasitos), pertencentes ao Domínio Tectônico Cabo Frio e ao terreno Oriental (domínio Costeiro) do orógeno Ribeira.A direção principal de suprimento sedimentar foi de sudoeste para nordeste, interpretada com base na identificação dos terrenos-fonte com abundante cianita no Domínio Tectônico Cabo Frio. Foi descartado o suprimento de sedimentos provenientes de noroeste, coincidente com a direção estrutural da faixa cataclasada de Colatina. As seqüências de quarta e quinta ordem analisadas não mostram variação na composição essencial, embora apresentem uma variação discreta na razão apatita:turmalina, que por isto apresenta potencial para ser utilizada como correlação entre os corpos de arenito dentro do campo. O índice ZTR baixo, combinado com a ausência de fragmentos metassedimentares e minerais pesados de baixo grau sugerem que ao final do Cretáceo os processos erosivos já haviam removido completamente as rochas supracrustais de baixo grau, expondo os terrenos plutônicos infracrustais. A composição quartzo-feldspática resultante favoreceu a qualidade dos reservatórios. A análise integrada dos dados sugere uma área-fonte tectonicamente ativa, relativamente próxima da bacia, submetida a um soerguimento rápido que permitiu a erosão de grandes volumes de sedimentos sob um regime de intemperismolimitado. Assim que erodidos das rochas-fonte os sedimentos foram transportados desde curtos rios de montanha e/ou leques aluviais rapidamente para águas profundas. A variação de alta freqüência da razão apatita:turmalina indica derivação direta dos arenitos do Campo de Jubarte a partir de um sistema aluvial relativamente próximo. / The application of integrated techniques of provenance analysis, including quantitative petrography using the Gazzi-Dickinson point-counting method, conventional heavy mineral analysis, garnet mineral chemistry and U-Pb zircon geochronology, allowed the identification of source-rocks and the sedimentary supply pattern for the Maastrichtian deep-water reservoir sandstones of the Jubarte Field, Campos Basin. The sandstones are poorly-sorted with angular to sub-angular grains denoting fast transportation. They present a detrital composition rich in feldspars (arkoses sensu Folk, 1968) and poor in finely-crystalline lithic fragments, with provenance from continental blocks of uplifted basement (sensu Dickinson, 1985). The heavy mineral assemblages indicate provenance from high-grade metamorphic rocks, derived from aluminous metapelites metamorphosed at high temperatures and low to medium pressures, from granites and from subordinate mafic rocks (metabasites), belonging to the Cabo Frio Tectonic Domain and the Oriental (Costeiro) terrain of the Ribeira orogen. The main sedimentary supply route during late Cretaceous was from southwest to northeast, indicated mainly by the presence of kyanite in the Cabo Frio Domain source-rocks. A possible dispersal pattern from northwest to southeast, coinciding with the Colatina shear zone, can be discarded. The fourth and fifth-order depositional sequences analyzed show no variation in major composition through time, although displaying a discrete variation of the apatite:tourmaline ratio, which thus present potential to be used as a parameter for sandstone correlation within the field. A low ZTR index coupled to the absence of low-grade heavy minerals and meta-sedimentary rock fragments suggest that at late Cretaceous the erosive processes had already removed the supracrustal, low-grade meta-sedimentary rocks, exposing the infracrustal plutonic terrains. The resulting quartz-feldspathic composition favored the quality of the reservoirs. The integrated analysis of compositional data suggests a tectonically-active source-area located close to the basin, where rapid tectonic uplift produced a large amount of sediments under a weathering-limited regime of erosion. Soon after being eroded from the bedrocks, these sediments were transported from short mountain rivers and/or by alluvial fans, directly to deep-water. The high-frequency variation inapatite:tourmaline ratio support direct derivation of Jubarte sandstones from a relatively proximal alluvial system.
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Reconhecimento geológico (Formações Santo Anastácio e Adamantna) e paleobiológico (Mesoeucrocodylia Baurusuchidae e Sphagesauridae) na região do estado de São PauloAgostinho, Marcelo Bonetti [UNESP] 27 February 2009 (has links) (PDF)
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agostinho_mb_me_rcla.pdf: 3099959 bytes, checksum: a6aef6db6a39facfb2f6de35a4e1c3a1 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente Trabalho objetiva o estudo dos afloramentos fossilíferos encontrados na região Noroeste do Estado de São Paulo, em especial nos arredores da Cidade de Jales. Os materiais fósseis encontrados pelo Autor compõem-se, em sua maioria, de crocodilomorfianos (Metasuchia Baurusuchidae e Sphagesauridae), resgatados em depósitos pertencentes especificamente às formações Santo Anastácio e Adamantina, Grupo Bauru. Os espécimens foram analisados e preliminarmente descritos, em conjunto com seus ambientes paleoecológicos e paleogeográficos. Análise litoestratigráfica, e confecção dos perfis de todos os afloramentos, permitirão algumas conclusões sobre os diferentes paleoambientes deposicionais. Procurou-se identificar os grupos taxonômicos da maneira mais especifica possível, relacionando o material em questão com os provenientes de outras regiões na mesma Bacia Bauru, na tentativa de estabelecer similaridades e/ou diferenças entre seus registros. Com isto contribui-se aos estudos sobre a evolução desta paleobiota, correlacionando-a aos processos evolutivos dos paleoambientes presentes nos diferentes estágios pelos quais esta estrutura bacinal passou ao longo do Cretáceo Superior. / The present Work aims the study of the fossiliferous outcrops found in the Northwestern area of the Sao Paulo State, especially in the surroundings of the Jales City. The fossil materials found by the Author are composed, in majority, by crocodylomorphs (Metasuchia Baurusuchidae and Sphagesauridae), specifically recovered in deposits from the Santo Anastácio and Adamantina formations, Bauru Group. The specimens were analyzed and described preliminarily, as well their paleoecological and paleogeographical contexts. Lithostratigraphical analysis, and outcrops sketchs, will allow some conclusions on the different paleoenvironmental depositions. Looking to identify the taxons in detail, relating and comparing them to specimens collected from other areas in the same Bauru Basin, it attempts to establish similarities and differences among these different records. So it contributes to the studies about the evolution of this paleobiota, correlating it to the evolutionary process of the paleoenvironments, in the different stages the Bauru Basin moved across through the Upper Cretaceous.
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