The study (MS, diploma thesis) is based on more than 1500 rudist samples from the Upper Cretaceous sediments of localities Písečný vrch and Na Stínadlech (near Teplice). Investigated samples come mainly from the collection of A. H. Fassel and were collected at the end of the 19th century, currently stored in the Regional museum in Teplice and National museum in Prague. The rudist shells were determined by generic and species levels, including five genera and eight species. The stratigraphic age of both localities has been a subject of discussion since the second half of the 19th century. In the recent decades, the opinion on the lower turonian age prevailed. However, five of the eight species present in the studied localities demonstrate the upper cenomanian age of the assemblages, making them probably the oldest known rudist-corals assemblages of its kind. The palaeoecological analysis and the ecological relationships proposal for the studied localities is based on the research in literature on palaeoecology and evolution of the rudists, also presented in the study. Key words: Bohemian Cretaceous Basin, Cenomanian - Turonian, rudists, corals, palaeoenvironment, Teplice rhyolite

Made available in DSpace on 2014-06-11T19:26:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-10-06Bitstream added on 2014-06-13T20:14:47Z : No. of bitstreams: 1 elias_fa_me_rcla.pdf: 3769559 bytes, checksum: f01a99ac620f8c79cf85423c0351edbf (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A utilização de dentes isolados, com finalidades taxonômicas, é reconhecida por diversos autores. No Hemisfério Norte investigações desta natureza são freqüentes, versando principalmente sobre micro e macromorfologias dentárias e sua utilização na identificação de grupos taxonômicos, eventualmente a categorias bastante específicas. No Hemisfério Sul, em especial no Brasil, estudos enfocando dentes isolados ainda representam uma parcela bastante sutil de contribuição no âmbito da Paleontologia. Esta contribuição representa o plano de investigação de um conjunto de dentes de amniotas, resgatados em um dos mais ricos e diversificados depósitos fossilíferos cretácicos do Estado do Maranhão: o afloramento Laje do Coringa. Situado na Ilha do Cajual, Município de Alcântara, representa um bone-bed com expressivo registro fossilífero do neo-Albiano/eo-Cenomaniano da Formação Alcântara, Bacia de São Luís- Grajaú. Considerando sua abundância e diversidade morfológica, os dentes fósseis dos depósitos cretácicos no Estado do Maranhão mostram-se potencialmente importantes no âmbito de investigações paleontológicas. A análise de parâmetros morfológicos aplicados à coroa, permitiu a identificação de 19 morfótipos dentários, representando terópodos (Carcharodontosauridae, Spinosauridae e Velociraptorinae), saurópodos (Titanosauria e Diplodocoidea), crocodilomorfos (Pholidosauridae) e pterossauros (Anhangueridae e Ornithocheiridae). A variedade morfológica evidenciada na amostra da Laje do Coringa sugere uma relativa diversidade paleobiológica e paleoecológica durante o neo-Albiano/eo- Cenomaniano do Estado do Maranhão... . / The use of isolated tooth, with taxonomic purposes, is recognized for many authors. In North Hemisphere inquiries of this nature are frequent, mainly treating about dental micro and dental macromorphologies and its use in the identification of taxonomic groups, eventually the very specific categories. In South Hemisphere, in especially Brazil, studies focusing isolated teeth still represent a very subtle parcel of contributions in the scope of Paleontology. This contribution represents the plan of inquiry of a amniotes teeth's set, rescued in one of richest and diversified Cretaceous fossiliferos deposits of the Maranhão State: the Laje do Coringa outcrop. Situated in the Cajual Island, Alcântara Municipality, it represents a bone-bed with expressive fossiliferous record in the late Albian/early Cenomanian of the Alcântara Formation, São Luís-Grajaú Basin. Considering its abundance and morphologic diversity, fossil teeth of the Cretaceous deposits in the Maranhão State reveal potentially important in the scope of paleontological inquiries. The analysis of morphologic parameters applied to the dental crown allowed the identification of 19 dental morphotypes, representing theropods (Carcharodontosauridae, Spinosauridae and Velociraptorinae), sauropods (Titanosauria and Diplodocoidea), crocodilomorphs (Pholidosauridae) and pterosaurs (Anhangueridae and Ornithocheiridae). The morphologic variety evidenced in the sample of the Laje do Coringa outcrop suggests a relative paleobiological and paleoecological diversity during the late Albian/early Cenomanian of the Maranhão State. As evidenced in studies developed for other authors (and confirmed in this inquiry) the paleofaunistical assemblage of the Alcântara Formation probably had a particular similarity with isochronous assemblages of the North of Africa, suggesting that the events of biological particularity in each one of continental... (Complete abstract, click electronic address below).

Orientador: Reinaldo José Bertini / Banca: Paulo Milton Barbosa Landim / Banca: Dilce de Fátima Rossetti / Resumo: A utilização de dentes isolados, com finalidades taxonômicas, é reconhecida por diversos autores. No Hemisfério Norte investigações desta natureza são freqüentes, versando principalmente sobre micro e macromorfologias dentárias e sua utilização na identificação de grupos taxonômicos, eventualmente a categorias bastante específicas. No Hemisfério Sul, em especial no Brasil, estudos enfocando dentes isolados ainda representam uma parcela bastante sutil de contribuição no âmbito da Paleontologia. Esta contribuição representa o plano de investigação de um conjunto de dentes de amniotas, resgatados em um dos mais ricos e diversificados depósitos fossilíferos cretácicos do Estado do Maranhão: o afloramento Laje do Coringa. Situado na Ilha do Cajual, Município de Alcântara, representa um bone-bed com expressivo registro fossilífero do neo-Albiano/eo-Cenomaniano da Formação Alcântara, Bacia de São Luís- Grajaú. Considerando sua abundância e diversidade morfológica, os dentes fósseis dos depósitos cretácicos no Estado do Maranhão mostram-se potencialmente importantes no âmbito de investigações paleontológicas. A análise de parâmetros morfológicos aplicados à coroa, permitiu a identificação de 19 morfótipos dentários, representando terópodos (Carcharodontosauridae, Spinosauridae e Velociraptorinae), saurópodos (Titanosauria e Diplodocoidea), crocodilomorfos (Pholidosauridae) e pterossauros (Anhangueridae e Ornithocheiridae). A variedade morfológica evidenciada na amostra da Laje do Coringa sugere uma relativa diversidade paleobiológica e paleoecológica durante o neo-Albiano/eo- Cenomaniano do Estado do Maranhão... (Resumo completo, clicar acesso eletrônico abaixo). / Abstract: The use of isolated tooth, with taxonomic purposes, is recognized for many authors. In North Hemisphere inquiries of this nature are frequent, mainly treating about dental micro and dental macromorphologies and its use in the identification of taxonomic groups, eventually the very specific categories. In South Hemisphere, in especially Brazil, studies focusing isolated teeth still represent a very subtle parcel of contributions in the scope of Paleontology. This contribution represents the plan of inquiry of a amniotes teeth's set, rescued in one of richest and diversified Cretaceous fossiliferos deposits of the Maranhão State: the Laje do Coringa outcrop. Situated in the Cajual Island, Alcântara Municipality, it represents a bone-bed with expressive fossiliferous record in the late Albian/early Cenomanian of the Alcântara Formation, São Luís-Grajaú Basin. Considering its abundance and morphologic diversity, fossil teeth of the Cretaceous deposits in the Maranhão State reveal potentially important in the scope of paleontological inquiries. The analysis of morphologic parameters applied to the dental crown allowed the identification of 19 dental morphotypes, representing theropods (Carcharodontosauridae, Spinosauridae and Velociraptorinae), sauropods (Titanosauria and Diplodocoidea), crocodilomorphs (Pholidosauridae) and pterosaurs (Anhangueridae and Ornithocheiridae). The morphologic variety evidenced in the sample of the Laje do Coringa outcrop suggests a relative paleobiological and paleoecological diversity during the late Albian/early Cenomanian of the Maranhão State. As evidenced in studies developed for other authors (and confirmed in this inquiry) the paleofaunistical assemblage of the Alcântara Formation probably had a particular similarity with isochronous assemblages of the North of Africa, suggesting that the events of biological particularity in each one of continental... (Complete abstract, click electronic address below). / Mestre

Le manteau lithosphérique subcontinental est exhumé au pied des marges passives distales non-volcaniques en réponse à l’amincissement extrême de la croûte continentale. Ce processus d’amincissement peut être étudié à pied sec sur les témoins de la paléo-marge passive nord Ibérique affleurant aujourd’hui au nord de la chaîne des Pyrénées dans les Chaînons Béarnais (Zone Nord-Pyrénéenne : ZNP). La ZNP résulte de l’inversion de bassins ouverts entre les plaques Ibérique et Europe pendant l’Albo-Cénomanien. Dans les Chaînons Béarnais, la couverture mésozoïque pré-rift est intimement associée aux roches du manteau subcontinental et à de fines lentilles tectoniques de croûte continentale. L’hyper amincissement crustal s’est déroulé dans des conditions thermiques relativement chaudes, comme le montrent les déformations ductiles syn-métamorphiques crétacées affectant la croûte continentale et la couverture mésozoïque allochtone, localement en contact tectonique sur le manteau exhumé. Dans cette thèse, nous présentons des données structurales et géochimiques apportant de nouvelles contraintes pour la connaissance du processus d’amincissement extrême de la croûte continentale et pour la reconstruction de l’évolution de la paléo-marge nord-Ibérique. La couverture pré-rift a été désolidarisée de son socle paléozoïque au niveau des évaporites du Keuper et mise en contact direct avec le manteau pendant son exhumation dans le fond des bassins. Le détachement croûte/manteau est une discontinuité majeure caractérisée par des bandes de cisaillements anastomosées définissant une fabrique lenticulaire (« phacoidal fabric ») d’épaisseur pluri-métrique au sommet du manteau serpentinisé. La croûte continentale se réduit à de minces écailles elles-mêmes anastomosées, séparée par des bandes de cisaillement dans le faciès schistes verts et évoluant vers des cataclasites plus froides. Les analyses par spectrométrie Raman sur la matière carbonée (RSCM) montrent que l’ensemble de la couverture mésozoïque a été soumis à des températures maximales comprises entre 200°C et 480°C. Elle est sujette à d’intenses circulations de fluides. Les interactions fluides/roches ont eu lieu lors de tous les stades de l’extension, depuis les contextes profonds durant la déformation ductile, jusqu’au domaine superficiel durant la déformation cassante. Le détachement manteau/Mésozoïque est marqué par une couche de roches métasomatiques, riches en talc, chlorite et pyrite, mises en place dans les conditions du faciès schistes verts, impliquant en partie des fluides issus de la serpentinisation du manteau. De plus, la géochimie isotopique (O, C, Sr) et les inclusions fluides présentes dans des veines de carbonates des sédiments mésozoïques, témoignent d’une circulation de saumures chaudes (~200°C), à travers toute la couverture sédimentaire pendant l’exhumation du manteau. Ces saumures sont issues de la dissolution des évaporites du Keuper, très rarement conservées dans les Chaînons Béarnais. Nous développons un modèle conceptuel basé sur la géologie des Chaînons Béarnais dans lequel la croûte continentale moyenne est déformée ductilement. Le fonctionnement de détachements contre-régionaux (à pendage vers le continent) est associé à l’individualisation de fines lentilles tectoniques de croûte continentale moyenne qui sont extraites et exhumées avec le manteau dans le fond des bassins albo-cénomaniens, laissant en arrière la croûte continentale supérieure et inférieure. Ces lentilles crustales collées au manteau forment alors une large zone de croûte extrêmement amincie. Des fenêtres ouvertes au sein de cette mince pellicule crustale permettent au manteau de venir en contact direct avec les sédiments pré-rifts (Saraillé, Turon de la Técouère). Des ouvertures au sein de la couverture pré-rift permettent au manteau de venir directement à l’affleurement (Urdach-Les Pernes). / Sub-continental lithospheric mantle rocks are exhumed at the foot of magma-poor distal passive margins as a response to extreme stretching of the continental crust. Remnants of the Northern Iberian paleo-passive margin are now exposed in the Northern Pyrenees in the Chaînons Béarnais (North Pyrenean Zone: NPZ) and represent field analogues to study the processes of continental crust thinning and subcontinental mantle exhumation. The NPZ results from the inversion of basins opened between the Iberia and Europa plates during Albo-Cenomanian times. In the Chaînons Béarnais ranges the pre-rift Mesozoic sedimentary cover is associated with peridotite bodies in tectonic contact with small size Paleozoic basement lenses. Continental extension developed under hot thermal conditions, as demonstrated by the syn-metamorphic Cretaceous ductile deformation affecting both the crustal basement and the allochtonous Mesozoic cover locally in direct contact with exhumed mantle rocks. In this study, we present structural and geochemical data providing new constraints to the knowledge of extreme crustal thinning processes and to reconstruct the evolution of the northern Iberia paleo-margin. The pre-rift cover was detached from its Paleozoic bedrock at the Keuper evaporites level and was welded to mantle rocks during their exhumation in the bottom of the basins. The crust/mantle detachment fault is a major shear zone characterized by anastomosed shear bands defining a plurimetric phacoidal fabric at the top of the serpentinized mantle. Raman Spectroscopy on Carbonaceous Materials (RSCM), performed on the Mesozoic cover reveals that the entire sedimentary pile underwent temperatures ranging between 200°C and 480°C. This sedimentary pile displays numerous evidence of infiltration by geological fluids. The fluid/rock interactions went on during the entire extensional events, since early deep phases characterized by ductile deformation, to late shallower stages characterized by brittle deformation. The detachment is marked by a layer of metasomatic rocks, locally up to 20 meters thick, made of talc-chlorite-pyrite-rich rocks that developed under greenschist facies conditions, including fluids derived from mantle rocks serpentinisation. Moreover, isotopes geochemistry (O, C, Sr) and microthermometry/Raman spectrometry of fluid inclusions in a network of calcitic veins (with quartz locally) in the overlying sediments reveal moderate temperatures (~220°C) brines circulation through the whole sedimentary cover during mantle exhumation. These brines likely derived from the dissolution of the local Triassic evaporites, rarely preserved in the Chaînons Béarnais. We developed a conceptual model based on geological evidence from the Chaînons Béarnais. Implying ductile deformation of the middle crust. Counter-regional detachments (dipping toward the continent) are associated to the individualization of mid-crustal thin tectonic lenses which remain welded on the mantle rocks and are exhumed at the floor of the Albian-Cenomanian basins, leaving behind the upper and the lower crust. These crustal lenses welded on mantle rocks then form a large zone of extremely thinned continental crust. Breaking points in this thin crustal sheet allow mantle rocks to come in direct contact with the pre-rift sediments (Saraillé, Turon de la Técouère). Breaking points in the pre-rift cover allow mantle rocks to be completely exhumed to the seafloor (Urdach-Les Pernes).

The biostratigraphy and isotope stratigraphy of the upper Aptian to lower Cenomanian interval including oceanic anoxic events OAE1b, 1c and 1d are investigated in ODP Site 763, drilled on the Exmouth Plateau offshore northwest Australia. Benthic foraminifera suggest that Site 763 was situated in outer neritic to upper bathyal water depths (~150-600 m). OAEs of the Atlantic basin and Tethys are typically associated with organic carbon-rich black shales and δ13C excursions. However, OAEs at this high latitude site correlate with ocean acidification and/or pyrite formation under anoxic conditions rather than black shales. Ocean acidification maybe responsible for sporadic low abundances of planktic foraminifera compared to radiolarians and benthic foraminifera associated with increased volcanogenic CO2 production during the formation of the Southern and Central Kerguelen Plateaus. Sea surface temperature may have cooled to 11°C in the late Aptian but increased gradually during the Albian. The Aptian/Albian boundary is placed at a negative carbon isotope excursion associated with the lowest occurrence of Microhedbergella renilaevis, typically found within the Niveau Kilian black shale of OAE1b. Third-order sea level cycles, particularly in the middle Albian, produced cyclic changes in the abundance of inoceramid prisms that increased during inferred times of falling sea level. The late Albian OAE1c and OAE1d coincide with horizons of intense pyritization and the absence of all biocomponents suggesting the development of euxinia. Warm Tethyan waters reached the Exmouth Plateau during the latest Albian based on the presence of thermocline dwelling keeled planktic foraminifera including Planomalina buxtorfi.

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ENGLISH SUMMARY Ammonite assemblage from the Upper Cenomanian of the Bohemian Cretaceous Basin realtively poorly known. Some species have been described herein for the first time: Thomelites cf. sornayi (Thomel) Euomphaloceras septemseriatum (Cragin) Eucalycoceras pentagonum (Gragin) and Allocrioceras annulatum (Shumard.). These records predominantly come from the M. geslinianum zone sediments developed in the higher parts of the Pecinov member (Uličný et al., 1998) of the Peruc - Korycany Formation. The sediments yielding ammonite assemblage represents the Late Cenomanian transgressive tract, accompanied by anoxic event OAE II = Oceanic anoxic Event II, CTBE) worldwide recorded in sediments and showing an increased content of stable isotope δ13 C. The OAE II is suggested to be connected to marine biota crisis and also the mass extinctionas well. The most affected organisms were benthic forms, due to high anoxic conditions at the bottom of the water column. Morphological features of the shells may, depending on the quality preservation shells (or cores) can be used to paleobathymetric interpretations. Most described species lived at depths of 50-80 m (up to 100m). Pelagic ammonites (i.e. Sciponoceras) lived at depths of up to 50 m. Heteromorphic taxa (Allocrioceras) have occurred at a depth of up to 100 m.