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Tognoli, Francisco Manoel Wohnrath [UNESP]. "Estratigrafia das seqüências deposicionais do grupo Guatá, borda leste da Bacia do Paraná." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/102978.
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tognoli_fmw_dr_rcla.pdf: 2467393 bytes, checksum: 266c2198d33d01d70f88787843e67770 (MD5)<br>Agência Nacional do Petróleo, Gás Natural e Biocombustíveis (ANP)<br>O Grupo Guatá foi alvo de um estudo detalhado ao longo de toda a borda leste da Bacia do Paraná. Por meio da análise e descrição seqüencial de testemunhos e integração com dados de perfis, aproximadamente 100 poços foram analisados desde o norte do Estado do Paraná até a região centro-sul de Santa Catarina. As fácies foram agrupadas em sucessões de fácies, a partir das quais foram definidos os padrões de empilhamento do tipo progradante, retrogradante e agradante, que em conjunto definem os tratos de sistemas e conseqüentemente as seqüências deposicionais. Além disso, foi realizado um estudo de integração entre sedimentologia, icnologia e geoquímica, que definiu critérios para a identificação e interpretação de superfícies com significado estratigráfico regional. Isso possibilitou correlacionar com segurança poços ao longo de toda a borda leste da Bacia do Paraná e mapear a distribuição das seqüências deposicionais de 3ª.e 4ª ordens. O arcabouço estratigráfico revelou que as seqüências são formadas pelos tratos de sistemas transgressivo e de mar alto ou apenas pelo trato de sistemas transgressivo. Notou-se também que as seqüências estão diretamente vinculadas aos principais lineamentos estruturais da bacia. Interpreta-se que as seqüências 1, 2, 3, 4 e 5 foram soerguidas ao longo de toda a borda leste da Bacia do Paraná, com sua expressão máxima na região do Arco de Ponta Grossa. Esse soerguimento gerou uma discordância angular com expressão regional sobre a qual foram depositadas as seqüências 6, 7 e 8. A seqüência 8 é marcada por subsidência entre os Alinhamentos do Rio Piquiri e São Jerônimo-Curiúva, contemporânea à deposição dos tratos de sistemas transgressivo e de trato de mar alto.<br>The Guatá Group was target of a detailed study along the eastern border of the Paraná Basin. Using integration of core description and well logs, approximately 100 wells were analyzed in Paraná and Santa Catarina states. Facies were grouped in facies successions, which allowed the recognition of the progradational, retrogradational and aggradational stacking patterns and, consequently, system tracts and depositional sequences. Moreover, it was performed an integration among sedimentology, ichnology and geochemistry as a way to obtain criteria for identifying and interpreting regional stratigraphic surfaces. This allowed a detailed correlation along the eastern border of Paraná Basin and the mapping of third and fourth order sequences. The stratigraphic framework has revealed sequences formed either by the transgressive and highstand system tracts or just by the transgressive one. The sequences are directly linked to the main structural linements of the basin. It is interpreted that sequences 1, 2, 3, 4 and 5 were uplifted along the eastern border of the basin, with the maximum expression in the region of the Ponta Grossa Arch. An angular unconformity was generated and sequences 6, 7 and 8 were deposited later in time. Sequence 8 was affected by subsidence between the Rio Piquiri and São Jerônimo-Curiúva linements, contemporaneous to deposition of the transgressive and highstand system tracts.
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Faria, Rafael Souza de 1985. "Lenhos fósseis das formações Irati e Teresina no estado de São Paulo : novos dados." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287308.
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Previous issue date: 2013<br>Resumo: A típica Flora de Glossopteris, que caracteriza o registro paleobotânico do Permiano da Bacia do Paraná possui como um importante componente os lenhos fósseis coniferóides. Aqui foram tomadas sete localidades do estado de São Paulo, de afloramentos da Formação Irati e da Formação Teresina, para as quais se estudaram os lenhos coniferóides encontrados. Os espécimes variam dentre lenhos associados ao corpo primário preservado e lenhos sem associação ao corpo primário preservado (traqueidóxilos). São descritos três taxa com base nos espécimes de lenho com corpo primário associado (todos da Formação Irati):Solenopitys rusticanaMussa, AbietopitysKräusel sp. e Atlanticoxylon bortoluzzii (Guerra) comb. nov. Além da combinação nova proposta, é também sugerida uma emenda ao morfogênero AtlanticoxylonMussa. Para os traqueidóxilos foram descritos cinco taxa (os três primeiros da Formação Irati e os dois últimos da Formação Teresina): AgathoxylonHartig, BrachyoxylonHollick etJeffrey, ProtobrachyoxylonHoldensp. 1, ProtobrachyoxylonHoldensp. 2 e ProtobrachyoxylonHoldensp. 3. A taxonomia dos traqueidóxilosutilizou-se de uma abordagem quantitativa associada à tradicional taxonomia baseada apenas em caracteres qualitativos. Optou-se por não classificar os espécimes formalmente além do nível genérico pelo confuso histórico da taxonomia de traqueidóxilos fósseis e para evitar uma inflação no número de taxa.Há evidências de xeromorfismo nos lenhos estudados: falsos anéis e interrupções do crescimento. Estas corroboram, junto de evidências sedimentológicas, a hipótese de que os ambientes deposicionais das formações Irati e Teresina estão associados à predominância de um clima árido. As evidências xeromórficas podem ainda ser relacionadas à presença de hifas fossilizadas em alguns dos espécimes coletados em Angatuba (Formação Teresina). A proliferação de fungos nos lenhos junto das condições de estresse hídrico retrata um momento de "tempos difíceis" para tais plantas. A fenologia foliar das coníferas retratadas pelos lenhos descritos foi também analisada e aponta para a Formação Irati a presença de uma comunidade vegetal majoritariamente composta de coníferas perenifólias, mas com alguns elementos decíduos, enquanto na Formação Teresina os dados sugerem uma comunidade quase estritamente composta de árvores perenifólias, com menos elementos decíduos. Por fim, os lenhos retratados apresentam similaridades anatômicas com os espécimes encontrados em camadas correlatas do Grupo Ecca, da Bacia do Karoo<br>Abstract: The Glossopteris Flora, which characterizes the palaeobotanical record of the Permian of the Paraná Basin, has as a significant component the fossil wood related to the Coniferales. Here, seven localities in the state of São Paulo, from outcrops of the Irati Formation and Teresina Formation where conifer fossil wood are found have been studied. Among the specimens, there are both fossil wood with primary body associated and with no primary body associated (tracheidoxyls). The specimens with primary body associated (all from Irati Formation) are included in the following taxa: Solenopitys rusticanaMussa, AbietopitysKräusel sp. and Atlanticoxylon bortoluzzii (Guerra) comb. nov. In addition to the new combination, an emended diagnosis of the morphogenus AtlanticoxylonMussais suggested. The tracheidoxyls studied are included in the following taxa: AgathoxylonHartig, BrachyoxylonHollick etJeffrey, ProtobrachyoxylonHoldensp. 1, ProtobrachyoxylonHoldensp. 2 e ProtobrachyoxylonHoldensp. 3. The taxonomy of the tracheidoxyls was not only based on a tradicional qualitative analysis, but used a quantitative approach. We preferred not to formally classify the specimens beyond the generic level in face of the confusing history of fossil tracheidoxyl taxonomy and to avoid an inflation of the number of taxa. There is evidence of xeromorphy in the wood analyzed suchas false growth rings and growth interruptions. These adaptations corroborate, along with the sedimentological data, the hypothesis of arid conditions on the deposition of the Irati and Teresina formations. The xeromorphic evidence may also be related to the presence of fossilized hyphae on some of the specimens collected in Angatuba (Teresina Formation). The fungi proliferation on the wood along with the xeromorphic features indicate that such plants grew in "hard times". The analysis of the leaf phenology of the conifers studied here shows a community majorly represented by evergreen trees for the Irati Formation, but with some deciduous elements. On the other side, in the Teresina Formation, the analysis shows an almost entirely evergreen community, with less deciduous trees than in the Irati Formation. Finally, the wood studied here show anatomic similarities with the wood found in the Ecca Group, in the Karoo Basin<br>Doutorado<br>Geologia e Recursos Naturais<br>Doutor em Ciências
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Pablo, Buenafama Aleman. "Acoustic impedance inversion of the Lower Permian carbonate buildups in the Permian Basin, Texas." Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/1068.
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Carbonate reservoirs are usually diffcult to map and identify in seismic sections due to their complex structure, lithology and diagenetic frabrics. The Midland Basin, located in the Permian Basin of West Texas, is an excellent example of these complex carbonate structures. In order to obtain a better characterization and imaging of the carbonate buildups, an acoustic impedance inversion is proposed here. The resolution of the acoustic impedance is the same as the input seismic data, which is greatly improved with the addition of the low frequency content extracted from well data. From the broadband volume, high resolution maps of acoustic impedance distributions were obtained, and therefore the locations of carbonate buildups were easily determined. A correlation between acoustic impedance and porosity extracted from well data shows that areas with high acoustic impedance were correlated with low porosity values, whereas high porosities were located in areas of low acoustic impedance. Theoretical analyses were performed using the time-average equation and the Gassmann equation. These theoretical models helped to understand how porosity distributions affect acoustic impedance. Both equations predicted a decrease in acoustic impedance as porosity increases. Inversion results showed that average porosity values are 5% [plus or minus] 5%, typical for densely cemented rocks. Previous studies done in the study area indicate that grains are moderately to well-sorted. This suggests that time-average approximation will overestimate porosity values and the Gassmann approach better predicts the measured data. A comparison between measured data and the Gassmann equation suggests that rocks with low porosities (less than 5%) tend to have high acoustic impedance values. On the other hand, rocks with higher porosities (5% to 10%) have lower acoustic impedance values. The inversion performed on well data also shows that the fluid bulk modulus for currently producing wells is lower than in non-productive wells, (wells with low production rates for brine and hydrocarbons), which is consistent with pore fluids containing a larger concentration of oil. The acoustic impedance inversion was demonstrated to be a robust technique for mapping complex structures and estimating porosities as well. However, it is not capable of differentiating different types of carbonate buildups and their origin.
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Glasspool, Ian James. "The palaeoecology of a South African Early Permian, and a Late Permian Australian, Gondwana coal." Thesis, Royal Holloway, University of London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325691.
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Zazzali, Sindbad. "Paléobiodiversité des ostracodes à la limite Permien moyen - Permien supérieur." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066111/document.
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Les ostracodes, microcrustacés (Arthropoda), sont relativement abondants dans les archives paléontologiques. Sensibles aux variations paléoenvironnementales, la composition des assemblages et leur diversité sont d’excellents marqueurs des changements qui affectent le benthos marin néritique. Leur diversité est connue pour être fortement affectée par la crise biologique marquant la limite Permien-Trias, mais leur histoire à la fin du Permien moyen reste peu documentée.Près de 10 Ma avant la limite Permien-Trias, à la fin du Permien moyen, un important épisode d’extinction intervient, préfigurant le déclin de la biodiversité à la fin du Paléozoïque.L’étude systématique des échantillons prélevés le long des coupes de Chaotian (province du Sichuan, Chine) et de Penglaitan (province du Guangxi, Chine) a permis l’identification de 115 espèces d’ostracodes, dont 7 nouvelles. Le travail réalisé sur ces coupes constitue la toute première étude des événements de la fin du Permien moyen et du début du Permien supérieur s’appuyant sur l’observation des assemblages d’ostracodes. L’état de conservation des carapaces d’ostracode, étudié lors de ce travail, enregistre les effets de la fin d’un épisode de régression et le début d’un épisode de transgression au sommet du Permien moyen à Penglaitan. Les résultats s’avèrent en accord avec les données lithologiques et paléontologiques présentées dans la littérature, un modèle de reconstitution paléoenvironnementale basé sur les données de préservation des ostracodes est proposé.Une analyse critique de la qualité du jeu de données a permis d’évaluer l’influence des biais d’échantillonnage sur la représentativité du matériel fossile dans les études sur la paléobiodiversité et la paléoécologie. Les biais peuvent être corrigés par un traitement méthodologique approprié qui rend valide la comparaison des données de biodiversité. La richesse générique et spécifique décroît sensiblement au cours du Capitanien. Le passage du Permien moyen au Permien supérieur enregistre une augmentation de la richesse spécifique, malgré une faible diversité générique. L’ordre des Palaeocopida apparait ici affecté par une baisse de diversité générique et spécifique au Wuchiapingien inférieur. Si ces résultats ne permettent pas pour l’iPermiannstant de caractériser un événement global de renouvellement des communautés d’ostracodes, l’étude de matériel fossile provenant d’autres régions du monde permettra de définir l’ampleur des phénomènes observés<br>Ostracods, microcrustaceans (Arthropoda), are quite abundant in the fossil record. Highly dependent to palaeoenvironmental conditions, their diversity and the assemblages’ composition are good indicators of changes affecting neritic marine benthos. Ostracods are known to be deeply affected by the Permian-Triassic crisis, but their history is poorly documented for the end of Middle Permian.About10 My before the Permian-Triassic boundary, the end of Middle Permian is characterized by a major extinction episode, which could be the first step of end-Palaeozoic biodiversity drop.Systematic study carried out on Chaotian section (Sichuan Province, P.R. China) and the Penglaitan section (Guangxi Province, P.R. China) samples allowed the identification of 115 species, including seven new species. The work carried out on these two sections provides the first study of end-Middle Permian extinction event, based on the observation of ostracod assemblages.Study of carapace preservation at Penglaitan section, highlighted the end of a regression phase and the beginning of a transgression phase at the top of Middle Permian. These results are relevant with lithologic and palaeontological data from literature. Thus, a palaeoenvironmental reconstruction model has been proposed, based on ostracod preservation data.An estimation of sampling bias consequences on fossil dataset representativeness in palaeobiodiversity and palaeoecology studies was realised. These biases could be corrected by an appropriate methodology allowing comparisons of biodiversity datum. Biodiversity data reveals a decrease of generic and specific richness during Capitanian. Specific richness increased passing the Middle-Upper Permian boundary. Palaeocopida order seems here affected by a generic and specific richness decline at basal Wuchiapingian. If these results do not allow for the time being to characterize a global ostracod turnover, further studies on material from other regions in the world will allow defining the extent of the observed phenomena
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Laya-Pereira, Juan Carlos. "Permian carbonates in the Venezuelan Andes." Thesis, Durham University, 2012. http://etheses.dur.ac.uk/3378/.
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In northern South America, Upper Palaeozoic strata were deposited extensively over peri-cratonic areas associated with restricted seas located between Laurentia and Gondwana, in equatorial Pangea. In many places the successions are rarely exposed, and so are poorly documented; this is largely the result of extensive weathering and dense vegetation in the tropical Andes. However, these strata do contain significant information for palaeogeographic and palaeoclimatic reconstructions, and our understanding of the evolution of northern Gondwana and the finally assembly of Pangea. The main objective of this thesis is the study of Permian carbonates in the Venezuelan Andes, their sedimentology, geochemistry, diagenesis and petroleum potential. The Palmarito sediments were deposited on a carbonate ramp that dipped basinwards towards the north facing the open ocean. The formation evolved from the underlying fluvial (Sabaneta Formation) through tidal-flat to mid-outer ramp deposits, with all facies recording a well-developed cyclicity. These strata fill an important gap in the regional palaeogeography and hence have revealed important implications for the palaeoclimate and palaeoceanography of the time. The results of this study of Palmarito strata have significant implications for the palaeogeography of this Permian time. From the facies analysis of the Palmarito Formation, new evidence has been provided for a central Pangean seaway. Furthermore, isotope analyses have improved the time-frame for the succession from 87/86Sr data, and in addition, the long-term stratigraphic trends in the δ13C and δ18O data have permitted interpretations of the climatic and oceanographic controls on Permian carbonate deposition. Moreover, metre-scale cyclicity shows the patterns of short-term controls on sedimentation, where autocyclic and allocyclic processes affected deposition and the vertical stacking of facies. An analysis of the diagenesis of the Palmarito carbonates shows several stages of cementation and alteration, although the strata are mainly fine-grained and coarse cements are rare. Finally the elements of the petroleum system for the Palmarito have been considered for the succession and as a result, it can be proposed that, firstly, fractures in finer-grained facies have the potential to provide reservoir rocks, and secondly, that although high values of Tmax have been obtained from rock-eval analysis from one locality, Palmarito strata do have the potential to form source rocks. Further investigation is required to ascertain the actual hydrocarbon potential of the Palmarito. The high content of finer-grained facies with low permeability provides the Palmarito strata a high potential to perform as a seal, as well as possibility to develop stratigraphic traps.
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Bin, Leman Mohd Shafeea. "Permian productidina of Britain and Malaysia." Thesis, Durham University, 1990. http://etheses.dur.ac.uk/6293/.
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The British Permian Productidina have not been revised in detail since 1858. In the present study some 2000 specimens from 29 localities in north east of England have been collected and prepared in the laboratory and used together with museum collections. The fauna consists of four species of Strophalosia, one new species of Eostrophalosia, six species of Heteralosia (four new), three species of Craspedalosia (one new), two species of Howseia, four species of Horridonia (one new) and two species of Spinohorridonia new genus. The Strophalosiacea and Horridoniinae are divided according to a new classification produced in this research. British Permian productidinid species are often strongly variable. Some variants suggest possible sexual dimorphism while others are probably of ecological forms. The fauna as a whole is unique and exclusive to the Upper Permian Zechstein Sea. The British Permian fauna shows major radiation periods during the early EZla Ca and early EZlb Ca. In conjunction with these radiations, the Productidina become divided into two distinct assemblages, marking two biozones introduced in this thesis, the Horridonia horrida and Strophalosia excavata biozones. Little is known of the Malaysian Permian Productidina. They comprise one species each of Strophalosia, Craspedalosia, Institella, Antiquatonia, Reticulatia, Echi- noconchus, Linoproductus, Siepanoviella, Striatifera, Liosotella (with new species), Marginifera?, Paucispinifera, Retimarginifera (with new species) and Costispinifera, two species of Dictyoclostus, Waagenoconcha and Echinauris and three species of Cancrinella. Lower Permian productidinids are associated with Artinskian fusulines and show links with the South Tethyan cold water fauna. Upper Permian producti dinids contain a mixture of North Cathaysian elements and the warm South Tethyan lyttoniid fauna. Variation occurs within some of the Malaysian species, but owing to lack of material, no final deductions can be made. Similarly, although significant differences are observed in Malaysian productidinid distributions, tabulation of biostratigraphic zonation is left until more data is available.
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Morante, Richard. "Permian-Triassic stable isotope stratigraphy of Australia." Phd thesis, Australia : Macquarie University, 1996. http://hdl.handle.net/1959.14/47568.
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"September, 1995"<br>Thesis (Ph.D.) -- Macquarie University, School of Earth Sciences, 1996.<br>Bibliography: leaves 171-183.<br>Introduction -- Australian ð¹³Corg-isotope profiles about the Permian-Triassic (P/TR) boundary -- Strontium isotope seawater curve in the late Permian of Australia -- ð¹³Cco₃ AND ð¹⁸Oco₃ seawater profiles through the Permian-Triassic of Australasia -- Paleomagnetic stratigraphy about the Permian/Triassic boundary in Australia -- Synthesis.<br>The Permian-Triassic boundary mass extinction is the largest in the Phanerozoic and therefore is the major event in the Phanerozoic. The mass extinction cause is problematical but studying global geochemical and geophysical signatures about the Permian-Triassic boundary can provide insights into the cause of the mass extinction. Global events about the Permian-Triassic boundary are marked by changes in: ð¹³C values of carbon ; ⁸⁷Sr/⁸⁶Sr in unaltered marine calcite ; magnetic polarity. -- This study aims to identify these features in the sedimentary record and to test the ca libration of the Australian biostratigraphical schemes to the global geological timescale. The following features are found in the Permian-Triassic sediments of Australia: a ð¹³Corg in Total Organic Carbon excursion in 12 marine and nonmarine sections from Northwest to Eastern Australia ; a ⁸⁷Sr/⁸⁶Sr minimum in a composite section mainly from the Bowen Basin ; a magnetic polarity reversal in the Cooper Basin, central Australia. The Australian sections are thus time correlated, as follows: The negative ð¹³Corg excursion indicates the Permian-Triassic boundary and occurs: 1) in Eastern and Central Australia at the change from coal measures to barren measures with red beds at the beginning of the Early Triassic coal gap; 2) in Northwest Australia about the boundary between the Hyland Bay Formation and the Mount Goodwin Formation in the Bonaparte Basin and at the boundary between the Hardman Formation and the Blina Shale in the Canning Basin. The base of the negative ð¹³Corg excursion lies at or near the base of the Protohaploxypinus microcorpuspalynological zone. The ⁸⁷Sr/⁸⁶Sr minimum determined about the Guadalupian/Ochoan stage boundary in North America is found in the Bowen Basin about the boundary between the Ingelara and Peawaddy Formations. The ð¹³Corg excursion in the Cooper Basin is near a magnetic reversal within the Permo-Triassic mixed superchron. The implications of these findings include: confirmation of the traditional placement of the Permian-Triassic boundary at the coal measures/barren measures with redbeds boundary in Eastern Australia ; the linking of the the Permian-Triassic boundary to a mass extinction of plant species on land and the beginning of the Triassic coal gap indicated by the Falcisporites Superzone base that is coincident with the negative ð¹³Corg excursion ; a mass extinction causal model that links the ⁸⁷Sr/⁸⁶Sr minimum determined about the Guadalupian/Ochoan stage boundary to a fall in sealevel that led to changing global environmental conditions. The model invokes greenhouse warming as a contributing cause of the mass extinction.<br>Mode of access: World Wide Web.<br>xii, 183 leaves ill., maps
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Gay, Susan Anne. "A Dicynodont fauna from the Permian of Tanzania." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.330250.
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Berry, Hunter D. "Dissolution of Permian Salt, Las Animas Arch, Colorado." Thesis, University of Louisiana at Lafayette, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10931832.
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<p> The Colorado Cheyenne 3D seismic survey in this thesis project is located in Cheyenne and Kiowa counties in eastern Colorado and features the Las Animas Arch. The scope of this project aims to expand the understanding of the processes and products of salt weld development. Throughout the survey, lateral variability of the Nippewalla strata within the Permian section is observed in both seismic and well data and generally is a result of dissolution of the Blaine or the dissolution of the Cedar Hills. </p><p> In this project, structural and stratigraphic elements were seismically mapped and interpreted with a focus on salt dissolution and welding. Overall, the characteristics of the dissolution in the strata covered by the 3D seismic survey of this study can be separated by a centrally-located dissolution front with the western half of the area having the lower Blaine halite removed by dissolution and the eastern half having the lower Blaine halite preserved. Dissolution of the upper Blaine halite is pervasive through the study area, especially within the western region due to remnant salt. </p><p> The eastern half of the survey is also affected by the dissolution within the Cedar Hills Formation. Unlike the Blaine, the amount of dissolution that occurs in the Cedar Hills seems fairly consistent, removing almost the complete formation or no dissolution at all. </p><p> This thesis is intended to serve as an initial investigation of the structural and stratigraphic relations due to dissolution of the Permian salts. Numerous additional questions remain beyond the scope of this thesis. </p><p>
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Gao, Zhifeng. "Lower Permian plants from Taiyuan, Shanxi Province, China." Thesis, Cardiff University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.506618.
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Twenty two genera containing thirty eight species and nine problematic taxa of fossil plants are described from the Lower Shihhotse Formation of the Lower Permian of Dongshan, Taiyuan, North China. They include three new genera, seven new species and two new combinations. Five genera and six species are rediagnosed. The plants described include sphenophylls, discinites, marattialeans, pecopterids, alethopterids, emplecopterids, sphenopterids, tingias, cycads, cordaites and possible conifers. Discinites dentilongii sp. nov. (Noeggerathiales) is described having disc-like sporophylls with a decurrent base. The marattialean fern Taiyuanitheca tetralinea gen. et sp. nov. has four rows of circular synangia on its pinnules. The evolution of the Marattiales is discussed. Tingia Halle and Tingiostachya Konno are rediagnosed with new morphological interpretations. Shuangnangostachya gracilis gen. et sp. nov. has spirally arranged sporophylls, each with two sporangia. This taxon is assigned to a new family. Much additional information on cycads has been gained from these assemblages,: Four species of the earliest known cycad megasporophylls are described and their taxonomy clarified. Based on the attachment of the megasporophylls of Crossozamia minor sp. nov. to an axis, new evolutionary pathways of the female cycad reproductive organs are proposed.. The later appearance of similar megasporophylls in Europe suggests that migration was from northern China westwards by dispersal of seeds in ocean currents. The associated leaf Yuania Sze and two of its species are rediagnosed". Tianbaolinia circinalis gen. et sp. nov. is considered to be an immature stage in cycad leaf development. On the evidence of the plants studied here, the climate during the early Permian in the Taiyuan area is suggested to have been warm and the humidity to have varied with local topography. The unique plants of this area reconfirm the independent nature of the Cathaysian flora.
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Pacheco, Cristian Pereira. "Descrição de uma nova espécie de anfíbio (Tetrapoda Temnospondyli) para a formação Rio do Rasto (Permiano da Bacia do Paraná) e revisão do status filogenético de Archegosauroidea." Universidade Federal do Pampa, 2015. http://dspace.unipampa.edu.br:8080/xmlui/handle/riu/508.
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Descrição De Uma Nova Espécie De Anfíbio (Tetrapoda Temnospondyli) Para A Formação Rio Do Rasto (Permiano Da Bacia Do Paraná) E Revisão Do Status Filogenético De Archegosauroidea.pdf: 1777717 bytes, checksum: e8fc95d895ea7e2478fb697730895325 (MD5)
Previous issue date: 2015<br>Temnospondyli é um grupo bastante diversificado de tetrápodes basais que surgiu
no início do carbonífero passando por grandes fases de radiação e extinção, com picos de
diversidade no Permiano e no Triássico. Dentro desse grande grupo inclui-se
Archegosauroidea, grupo abundante no Leste Europeu, com registro ainda escasso na
América do Sul (até o momento, restritos ao Brasil). Esse grupo é dividido em duas
famílias, Archegosauridae e Melosauridae. Até então, os registros indiscutíveis de
arquegossauróides formalmente descritos para o Gondwana pertenciam à família
Archegosauridae, a saber: Prionosuchus plummeri um platiopossauríneo encontrado no
estado do Maranhão (Formação Pedra de Fogo) e Bageherpeton longignathus encontrado no Rio Grande do Sul na divisa entre Bagé e Aceguá (Formação Rio do Rasto). Neste trabalho apresenta-se a descrição e análise filogenética do espécie basal do gênero Konzhukovia (anteriormente exclusiva da Rússia) para o Permiano do Gondwana permite fazer novas considerações acerca de sua origem e irradiação, que tanto pode ter se dado na Laurasia com Konzhukovia sendo parte da primeira irradiação de arquegossauróides para o Gondwana ou mesmo Konzhukovia ter se originado no Gondwana e migrado para a Laurásia onde as espécies mais derivadas evoluíram. Além disso, o fato de Konzhukovia fazer parte de uma família basal a Stereospondyli reforça a hipótese de que estes se originaram e diversificaram no Oeste do Gondwana antes do fim do Permiano ao contrário do que sugere a hipótese de que os Stere ospondyli teriam ficado em um refúgio no Leste do Gondwana e teriam se diversificado após a grande extinção no final do Paleozóico.<br>Temnospondyli is a very diverse group of basal tetrapods that appeared in the Early
Carboniferous, going through major phases of radiation and extinction, with peaks of
diversity during Permian and Triassic. It includes the Archegosauroidea, an abundant
group in Eastern Europe with a few records from South America (so far restricted to
Brazil). Achegosauroidea is divided into two families, Archegosauridae e Melosauridae.
Until this contribution, unquestionable records of formally described archegosauroids from
Gondwana belong to the Archegosauridae, as follows: The platyoposaurinae Prionosuchus
plummeri from the Maranhão state (Pedra de Fogo Formation) and Bageherpeton
longignathus from the Rio Grande do Sul state (Rio do Rasto Formation). This work
presents the description and phylogenetic analysis of the first indubitable tryphosuchine
outside Eastern Europe. The new material (UNIPAMPA PV 00137) consists in a partially
complete skull collected in 2008 in the Posto Queimado locality (that also belongs to the
Rio do Rasto Formation) from São Gabriel municipality, Rio Grande do Sul state. In the
phylogenetic analysis presente
Russia) in the Permian of Gondwana provide new insights about its radiation and
dispersion, which may have happend on Laurasia with Konzhukovia being part of the first
irradiation of archegosauroid to Gondwana or with konzhukovia originated on Gondwana
and migrated to Laurasia, where the derivated species evolved. Besides, the fact that
Konzhukovia belongs to a basal family to Stereospondyli reinforces the hypothesis that
these ones are originated and diversificated in the West of Gondwana before the end of
Permian. However, it is unlikely the hypothesis that the Stereospondyli may have stayed in
a refuge in the East of Gondwana and may have diversificated after the great extinction in
the end of Paleozoic period.
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Faria, Rafael Souza de 1985. "Licofitas Guadalupianas da Bacia do Parana : Novos dados morfo-anatomicos." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287313.
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Previous issue date: 2009<br>Resumo: Lycopodiopsis derbyi é a espécie à qual mais comumente se relacionam os fragmentos caulinares licofíticos encontrados em estratos guadalupianos da Bacia do Paraná. Tipicamente caracteriza-se por um cilindro vascular sifonostélico com o anel descontínuo cortado por raios medulares e pela presença de almofadas foliares rômbicas com vesícula infrafoliar e cicatrizes foliares sem sinais de páricnos. Microfilos fragmentados geralmente ocorrem associados aos caules. Aqui foram tomadas três localidades no estado de São Paulo (de afloramentos da Formação Corumbataí), uma no estado do Paraná e uma em Santa Catarina (ambas de afloramentos da Formação Teresina) para as quais se estudaram os caules e microfilos de licófitas encontrados. Os caules foram diagnosticados como L. derbyi. Análises morfológicas levaram a sugestão de um possível modelo ontogenético relacionando as almofadas foliares e o diâmetro dos ramos. Nas análises anatômicas interpretou-se o córtex de maneira diferente a de autores anteriores. Com base nos dados adquiridos propõe-se uma emenda à diagnose da espécie e ainda sugere-se uma modificação da chave de identificação de Thomas e Meyen (1984) para as Lepidodendrales do Paleozóico superior. Para os microfilos definiu-se uma nova organo-espécie com base em amostras de Piracicaba (SP), Lepidophylloides corumbataensis. Tal organo-espécie é a primeira do gênero formalmente descrita para o Brasil e possivelmente para o Gondwana. Representa ainda o primeiro registro de tecido paliçádico numa espécie de Lepidphylloides. A organização dos fexies de xilema em forma de crescente sugere uma proximidade às espécies da Catásia. A íntima associação com Lycopodiopsis derbyi indica que provavelmente representem as folhas dos mesmos. Compararndo as ocorrências de microfilos estudadas nas formações Teresina e Corumbataí, concluiu-se que na primeira aqueles ocorrem r em menores concentrações e sem anatomia preservada, indicando maior transporte.<br>Abstract: Master degree dissertation Rafael Souza de Faria Lycopodiopsis derbyi is the most common species to which the lycopod stem fragments found in the Guadalupian strata from the Paraná Basin are assigned. A vascular cylinder represented by a siphonostele with a discontinuous ring crossed by medular rays and the presence of rhombic leaf cushions with infrafoliar bladders and leaf scars without any sign of pharichnos typically characterize the species. Fragmented microphylls occur in general associated with the stems. Here three localities in the state of São Paulo (from outcrops of Corumbataí Formation), one in Paraná state and one in Santa Catarina state (from outcrops of Teresina Formation) where lycopods stems and microphylls are found have been studied. The stems were diagnosed as L. derbyi. Morphological analyses suggest a possible ontogenetic model relating the leaf cushions to the branch diameter. In the anatomical analyses the cortex was
interpreted differently from previous authors. Based on the data acquired an emended diagnoses is proposed for the species together with a modification of the Thomas and Meyen's (1984) identification key for the Upper Paleozoic Lepidodendrales. With regard to the microphylls, a new organo-species based on samples from Piracicaba (São Paulo state) was defined, Lepidophylloides corumbatensis. This organo-species is the first of the genus formally described for Brazil and probably for Gondwanaland. It also represents the first register of palisade tissue in a Lepidophylloides species. The xylem bundle organization in crescent shape suggests a close relation with the catasian species The association with Lycopodiopsis derbyi indicates that they represent the leaves of the such stems. Comparing the mycrophylls studied from the Teresina and Corumbataí formations, the ones occuring in the first are commonly in lower concentrations and with no preserved anatomy, indicating more transport.<br>Mestrado<br>Geologia e Recursos Naturais<br>Mestre em Geociências
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Carroll, Paul Geoffery. "Pre-Permian structure and prospectivity at Gidgealpa, South Australia /." Title page, contents and abstract only, 1990. http://web4.library.adelaide.edu.au/theses/09SM/09smc3195.pdf.
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Thesis (M. Sc.)--University of Adelaide, National Centre of Petroleum Geology & Geophysics, 1992.<br>Vol. 2 consists of 30 col. & folded maps & charts. Includes five overlays in vol. 1. Includes bibliographical references (leaves 152-162).
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Perez, Ramos Olivia 1946. "Permian biostratigraphy and correlation between southeast Arizona and Sonora." Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/558194.
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Boos, Alessandra Daniele da Silva. "Os terápsidos da Formação Rio do Rasto (Guadalupiano/Lopingiano, Bacia do Paraná): morfologia, taxonomia e aplicações bioestratigráficas." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/140194.
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Localidades contendo tetrápodes fósseis do Permiano são conhecidas para a Formação Rio do Rasto (FRR) no sul do Brasil desde a década de 1970. Posteriormente, elas foram agrupadas em três “faunas locais”, correlacionáveis com as ocorrências de tetrápodes do Guadalupiano e do Lopingiano da África do Sul e da Rússia. Contudo, os fósseis de tetrápodes no Brasil ocorrem em afloramentos dispersos, isolados e discontínuos, de maneira que a maioria deles não possui dados precisos referentes ao seu posicionamento estratigráfico no sítio de coleta. Sugere-se que seja suspenso o uso do termo “fauna local” para as localidades contendo tetrápodes da FRR, pois elas provavelmente agrupam táxons que não são contemporâneos. A presente tese reconheceu dez localidades contendo tetrápodes nesta formação, mas apenas em quatro delas há o registro de terápsidos (Serra do Cadeado-EFCP, Fazenda Fagundes, Fazenda Boqueirão e Tiarajú-Barro Alto). Até o momento, terápsidos permianos são reportados na América do Sul apenas na FRR e compreendem anomodontes e dinocefálios. Aqui são relatadas duas novas ocorrências de terápsidos para esta unidade. O espécime UFRGS-PV-0487P foi identificado como um Tapinocephalidade indeterminado (Dinocephalia) e provém da localidade Serra do Cadeado-EFCP. Comparação com outros Tapinocephalidae indicam que UFRGS-PV-0487P é um espécime juvenil ou sub-adulto, semelhante a Moschops e Moschognathus da Zona de Assembleia (ZA) de Tapinocephalus da África do Sul. A segunda ocorrência de terápsido reportada aqui é baseada no espécime UNIPAMPA-PV-317P, reconhecido como um novo gênero e espécie de anomodonte (especificamente um dicinodonte). Características diagnósticas do novo táxon incluem cristas bem desenvolvidas (em norma ventral) a partir da placa mediana do pterigoide e ao longo dos ramos anteriores do pterigoide, ângulo marcado da porção posterior dos ramos do pterigoide, presença de pequenas presas caniniformes a partir de uma pequena incisura levemente posterior a cada processo caniniforme e presença de um processo retro-articular bem desenvolvido e em forma de bulbo na mandíbula. Não está claro ainda se o tamanho reduzido das presas caniniformes é devido à ontogenia, patologia ou a dimorfismo sexual. A análise filogenética indicou que UNIPAMPA-PV-317P é o membro mais basal de Bidentalia, um clado cosmopolita que inclui a maioria dos dicinodontes permianos e triássicos. Em relação às correlações bioestratigráficas possíveis para as localidades contendo tetrápodes na FRR, não é possível correlacionar estas localidades com apenas uma das ZAs da África do Sul ou mesmo da Plataforma Russa no momento, por que a FRR parece abrigar múltiplas assembleias de tetrápodes, das quais um retrato muito tendenciado é conhecido. Apenas a localidade de Aceguá Sítio 1 indica um pequeno refinamento, visto que os níveis abaixo da ocorrência de Provelosaurus americanus (um pareiassaurídeo) foram datados com métodos radiométricos e indicaram ser mais recentes do que 265 Ma, demonstrando que este sítio é correlacionável a partir da ZA de Tapinocephalus.<br>Permian tetrapod-bearing localities have been recovered from the Rio do Rasto Formation (RRF) in southern Brazil since the 1970s. Posteriorly, they have been grouped into three ‘local faunas’, correlated with the Guadalupian and Lopingian tetrapods of South Africa and Russia. However, tetrapod findings in the Brazilian deposit occur in disperse, isolated and discontinuous outcrops and most specimens lack precise data regarding their stratigraphic provenance. We suggest that the term ‘local fauna’ be discontinued for the tetrapod-bearing localities of the RRF, since they may be grouping non-contemporaneous taxa. The present study recognized ten tetrapod-bearing localities in this formation, but only four of them bear therapsid remains (Serra do Cadeado-EFCP, Fagundes Farm, Boqueirão Farm and Tiarajú-Barro Alto). Until date, Permian therapsids in South America are only known from the RRF and comprise anomodonts and dinocephalians. Here we report two new therapsid occurrences for this unit. The specimen UFRGS-PV-0487P was identified as a Tapinocephalidae indet. (Dinocephalia), from the Serra do Cadeado-EFCP locality. Comparison with other tapinocephalids indicates that UFRGS-PV-0487P is a juvenile or sub-adult specimen, which most closely resembles the ‘moschopines’ Moschops and Moschognathus from the Tapinocephalus Assemblage Zone (AZ) of South Africa. The second occurrence is based on the specimen UNIPAMPA-PV-317P, recognized as a new genus and species of anomodont (namely a dicynodont). Diagnostic features of the new taxon include well-developed ridges extending from the crista oesophagea anteriorly along the pterygoid rami, strong posterior angulation of the posterior pterygoid rami, small tusks erupting from a short incisure slightly posterior to each caniniform process and well-developed bulbous retroarticular process of the articular. It is not clear whether the reduced size of the tusks represents pathology, an ontogenetic feature or sexual dimorphism. Phylogenetic analysis indicates that UNIPAMPA-PV-317P is the most basal member of Bidentalia, a cosmopolitan clade that includes most of the Permian and Triassic dicynodonts. It is not possible at the moment to constrain the time interval of the tetrapod-bearing localities of the RRF to only one biozone of South Africa or Russia because the RRF seems to bear incomplete but multiple faunal assemblages. Aceguá Site 1 age is better constrained due to radiometric dating, but it only indicates that the levels bearing the pareiasaurid Provelosaurus americanus are younger than 265 My and can be correlated with the Tapinocephalus AZ.
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Paulo, Pedro Oliveira [UNESP]. "Vertebrados fósseis do estado de Goiás, com ênfase em sua fauna de amniotas, compreendida entre o período permiano e a época pleistoceno." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/92871.
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paulo_po_me_rcla.pdf: 7478896 bytes, checksum: b407d0e66ef447d5ae6f5f6dd9e88ff6 (MD5)<br>Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)<br>Embora possua significativas áreas com depósitos sedimentares, o Estado de Goiás apresenta-se quase inexplorado quanto aos vertebrados fósseis. O principal objetivo desta investigação foi reunir, em um único trabalho, todas as ocorrências de paleovertebrados de Goiás, compreendidos entre o Período Permiano e a Época Pleistoceno, a partir das referências bibliográficas disponíveis e dos materiais depositados em algumas coleções brasileiras. No Estado de Goiás ocorrem significativas áreas de exposição de estratos paleozóicos, da Bacia do Paraná. Destacam-se as formações Irati e Corumbataí, cujas idades correspondem respectivamente aos Permianos Inferior e Médio. Para a Formação Irati têm sido reportadas ocorrências de restos de mesossauros, desde os primeiros levantamentos geológicos empreendidos em Goiás, em meados dos anos 1930. Para a Formação Corumbataí, os restos coletados em Goiás limitam-se a fragmentos de escamas e dentes de peixes, ainda inéditos. No Estado de Goiás ocorrem também significativas áreas de exposição de afloramentos das unidades componentes da Bacia Bauru, de idade Cretáceo Superior. Correspondem às formações Adamantina e Marília, aflorantes em amplas áreas ao Sul do estado. Destas unidades foram anotadas ocorrências de restos dinossaurianos na região Sudoeste, especialmente no Membro Echaporã da Formação Marília. Coberturas superficiais pleistocênicas são encontradas em áreas correspondentes aos interflúvios dos principais rios. Algumas destas forneceram significativas quantidades de restos atribuíveis a megafauna pleistocênica, especialmente em localidades nunca antes reportadas, como Goiânia e Niquelândia. As cavernas de Goiás forneceram expressiva quantidade de materiais pleistocênicos / holocênicos, de grande interesse ao estudo da diversidade das comunidades...<br>Despite significant areas with sedimentary strata, and great possibility for prospections of fossil remains, the Goias State is still barely explored. The main objective of this work is to gather, in one contribution, all occurrences of paleovertebrates of the Goiás State, from Permian Period to Pleistocene Epoch. The informations for this compilation are based on available literature and Brazilians museums and collections. In the Goiás State there are considerable areas with exposition of Paleozoic strata, being related to the Paraná Basin. The Irati and Corumbataí formations are respectively related to Lower and Middle Permian. For the Irati Formation there has been reported the occurrence of mesosaurs, since the first geological studies performed in Goias, during the 1930s. For the Corumbataí Formation, the remains collected in the state are restricted to fragments of fishes teeth and scales, still not published. In the Goiás State there are substantial areas of the Bauru Basin, from the Upper Cretaceous. They are associated to the Adamantina and Marília formations, geological unities occurrying on areas situated Southern Goiás State. From these units there have been reported the occurrence of dinosaur remains, especially in the Echaporã Member from the Marília Formation. Pleistocenic deposits are commonly found in areas corresponding to ridges between the most important rivers. Some of these regions provide relevant amounts of remains, associated the Giant Pleistocene Fauna, especially in localities never reported before, just as Goiânia and Niquelândia. Goiás State caves also provided an abundant amount of Pleistocenic / Holocenic remains, of great importance for the study of the diversity of vertebrates communities during this chronological transition. Among the most important catalogued families are Didelphidae, Dasypodidae, Phylostomidae, Natalidae, Vespertilionidae... (Complete abstract click electronic access below)
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Chahud, Artur. "Geologia e paleontologia das formações Tatuí e Irati no centro-leste do Estado de São Paulo." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/44/44141/tde-29102012-120319/.
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A área de ocorrência das formações Tatuí e Irati, na região centro-leste do Estado de São Paulo, entre as cidades de Leme e Rio das Pedras é objeto desta pesquisa. São detalhadas as ocorrências destas duas formações, através de seções estratigráficas, caracterizando e analisando as sucessões de litotipos, conteúdo fossilífero, tafonomia dos fósseis, além de enfocar hipóteses paleoecológicas e paleoambientais. Na FormaçãoTatuí foram identificadas quatro fácies, a inferior de arenitos finos e paleoambiente incerto, duas refletindo contexto não marinho e a de topo com influência marinha. As duas fácies do contexto predominantemente não marinho são respectivamente siltitos arenosos com fósseis de água doce e arenitos grossos ou conglomeráticos, fácies Ibicatu, localmente com lenhos. A fácies de topo é caracterizada por depósitos de arenitos finos, ocasionalmente com grandes estratificações cruzadas, estratificações \"hummockies\", apropriado para um grande corpo d\'água salino. O conteúdo fóssil da Formação Tatuí inclui três tipos de icnofósseis em três fácies diferentes (fácies basal do estudo, Ibicatu, e no topo), grandes caules vegetais (pteridófitas e espermatófitas) na fácies Ibicatu, crustáceos (conchostráceos e fragmentos indeterminados) ocorrem na fácies síltica, escamas, dentes e partes ósseas de peixes ósseos na fácies siltica e topo da Formação Tatuí. O Membro Taquaral é reconhecido por duas fácies e dois paleoambientes de salinidade variável. A fácies basal, composta de arenitos finos a conglomeráticos, granulometria irregular horizontal e verticalmente e com ictiofósseis, é interpretada como depositada em ambiente raso dominado por ondas. A segunda fácies, folhelhos sílticos, é típica de paleoambientes mais calmos, provavelmente com menor salinidade. Os fósseis da base arenosa do Membro Taquaral são peixes, representados por Chondrichthyes sob a forma de dentes cladodontes, espinhos de Euselachii (Amelacanthuse Iratiacanthus), espinhos Ctenacanthiformes (Sphenacanthus sanpauloensis eS. sp.), dentes de Xenacanthiformes, Diplodoselachidae (Taquaralodus albuquerquei) e Xenacanthidae, dentes de Orodontiformes, (Orodus ipeunaensis), Petalodontiformes (Itapyrodus punctatus eI. sp.) e Holocephali indeterminados. A fauna de Osteichthyes é a mais abundante em número de espécimes, sendo composta, predominatemente, de dentes e escamas paleoniscóides, raras escamas de Coelacanthimorpha, partes ósseas e dentes labirintodontes, estes atribuídos a Osteolepiformes e a tetrápodes Temnospondyli. Os fósseis estão normalmente dispersos e desarticulados e os elementos ósseos fragmentados e desgastados. O conteúdo fóssil da fácies folhelho síltico do Membro Taquaral é raro, os mais comuns são crustáceos, principalmente do gênero Clarkecaris, e restos muito fragmentados de Coelacanthimorpha e Palaeonisciformes.<br>The following Paraná Basin, Late Paleozoic lithoestratigraphic units, the upper part of the Tatuí Formation, located under the lower partof the Irati Formation, Taquaral Member are cropping out at center-eastern State of São Paulo, Brazil, between Rio das Pedras and Leme. The lithologies, fossil contents and taphonomy ofthese units are studied through stratigraphic sections, allowing the formulations of paleoecological and paleoenvironmental hypothesis. Four facies were recognized at the top of the Tatuí Formation stratigraphic sections which were interpreted as following; the basal an uncertain paleoenvironment of deposition, two paleoenvironmental contexts; mostly continental and one under deposits marine influence. The two facies interpreted as mostly continental are respectively, sandy-siltstones facies with freshwater fossils and coarse to conglomeratic sandstone, Ibicatu facies, locally with log plants. The top facies, interpreted as under a marine influence, is characterized by deposits of fine sandstones, occasionally with large cross beds, hummockies, and, locally, tidal deposits, suited for a large body, of saline water. The fossil content of Tatui Formation include three kinds of trace fossils in three different facies (basal, Ibicatu and top respectively), large stem plants (Pterydophyta and Spermatophyta) in the Ibicatu deposit, with indeterminated fragments of crustaceans and conchostraceans, found out in the siltstone facies and scales, teeth and bone pieces, found out in siltstone and of the top facies. Two facies were recognized at the Taquaral Member. The basal are fine to conglomeratic sandstone with irregularly grain size both horizontal and vertically, with ichthyofossils. Itis interpreted as laid down in a salty shallow water dominated by waves. The second are silty shale laid down in low saline water. The fossils of the sandy facies are Chondrichthyes: cladodontes teeth, Euselachii finspines (Amelacanthus and Iratiacanthus santamariaensis), Ctenacanthiformes finspines (Sphenacanthus sanpauloensisand S.sp.), Xenacanthiformes teeth, Diplodoselachidae (Taquarodus albuquerquei) and Xenacanthidae, Orodontiformes: Orodus ipeunaensis, Petalodontiformes (Itapyrodus punctatus andI. sp.) and undetermined Holocephali. The fauna of Osteichthyes, the most abundant in number of specimens are predominantly paleoniscoid teeth and scales, rare Coelacanthimorpha scales, labyrinthodonts bones and teeth, assigned to Osteolepiformes and tetrapods Temnospondyli. The fossils are usually scattered, disorganized, fragmented and worn. The fossil content of the Taquaral silty-shale facies is meager, the most common are crustaceans, mainly of the genus Clarkecaris, and very fragmented remains of Coelacanthimorpha and Palaeonisciformes.
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Clark, James Anthony. "Controls on the distribution of upper Jurassic fulmar sandstones on the West Central Shelf, UK Central North Sea." Thesis, Imperial College London, 1999. http://hdl.handle.net/10044/1/8873.
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Saila, Laura K. "Leptopleuron, anomoiodon and the Russian Permian procolophonoids: a study of the interrelationships, evolution and palaeobiogeography of procolophonoidea." Thesis, University of Bristol, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492478.
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The parareptilian group Procolophonoidea has been increasingly studied in recent years, and a high survival rate during the P/Tr extinction event has been estimated tor the ciade. Procolophonoid interrelationships, however, remain poorly known. Here, descriptions of the procolophonids Anomoiodon liliensterni and Leptopleuron lacertinum, and the possible Permian Russian procolophonoids, are provided. Anomoiodon and the genus Kapes were found to be closely related but there is not enough evidence to support the synonymy of the two genera. Leptopleuron is described in great detail, making it one of the most completely knovm procolophonoids. Of the possible Permian Russian procolophonoids, Suchonosaurus minimus was found to be a member of the more inclusive Procolophonidae, whereas Microphon exiguus and Kinelia broomi fall outside of Procolophonoidea. Nyctiphruretus acudens might be the sister taxon of Procolophonoidea but an alternative hypothesis of Nyctiphruretus being more closely related to pareiasaurs and nycteroleterids also received support, A phylogenetic study. including 39 procolophonoid taxa, was conducted. The results suggest novel compositions of the procolophonid clades Leptopleuroninae and Procolopphoninae; the monophyly of the genus Kapes was questioned; the phylogenetic position of Suchonosaurus, Pintosaurus and Phaantosaurus among the other basal procolophonids remains unresolved; and the results cast doubt on Procolophonoidea being divided into the clades Owenettidae and Procolophonidae. The topology with the best stratigraphic fit indicates that only 57% of procolophonoid lineages might have survived through the P/Tr boundary. However, it is also possible that up to 80% lineages crossed the boundary but this requires a scenario that maximizes the number of ghost lineages. A stratigraphical analysis supports separate Owenettidae and Procolophonidae.
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Foster, William J. "Palaeoecology of the late Permian mass extinction and subsequent recovery." Thesis, University of Plymouth, 2015. http://hdl.handle.net/10026.1/5467.
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Climate warming during the latest Permian is associated with the most severe mass extinction event of the Phanerozoic, and the expansion of hypoxic and anoxic conditions into shallow shelf settings. Our understanding of the magnitude, pattern and duration of the extinction event and subsequent recovery remains equivocal. Evidence suggests that the action of waves provided an oxygenated refuge, i.e. ‘habitable zone’, above wave base that may be limited to high latitudes, in association with a faster pace of recovery. In addition, advanced recovery faunas have been documented from the Induan and there is evidence from the pelagic realm that further biotic crises may have delayed the recovery of benthic organisms coinciding with large carbon isotope perturbations at the Lower Triassic sub-stage boundaries. To test these hypotheses, novel palaeoecological data was collected from localities in Hungary, northern Italy, and Svalbard. To understand better the ecological impact of the extinction, a database of all known benthic marine invertebrates from the Permian and Triassic periods was created, with each taxon assigned to a functional group based on their inferred lifestyle. This study found that the skeletal and ichnofaunal assemblages consistent with advanced ecological recovery are limited to settings aerated by wave activity, which supports the habitable zone hypothesis. In the western Palaeotethyan sections it was found that the proximal end of the ‘habitable zone’ was limited by persistent environmental stress attributed to increased runoff that resulted in large salinity fluctuations, increased sedimentation rates and eutrophication creating an environment only favourable for opportunistic taxa. In the Tirolites carniolicus Zone, however, the ‘habitable zone’ expands into more proximal and offshore settings. This is associated with climate cooling in the late Spathian. The data also demonstrate that despite the taxonomic severity of the extinction, only one mode of life went extinct and only one subsequently evolved in the aftermath. Functional diversity was, however, reduced in particular regions and environmental settings, and recovery varied spatially and temporally. In western Palaeotethys, benthic communities record evidence for biotic crises, such as reduced tiering in the Smithian, associated with Early Triassic carbon isotope excursions, but, until the Spathian there was no significant change in the composition of the benthic faunas.
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De, Blanger Keith. "The effect of the Permian mass extinction on shark faunas." Thesis, University of Bristol, 2005. http://hdl.handle.net/1983/98e915c9-71a4-4dd4-b66c-9d8a266abf3f.
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Platt, Jacqueline D. "The diagenesis of early Permian Rotliegend deposits from northwest Germany /." [S.l.] : [s.n.], 1991. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Tarailo, David A. "Diversity and dispersal trends following the latest-permian mass extinction." Diss., University of Iowa, 2018. https://ir.uiowa.edu/etd/6649.
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The latest-Permian mass extinction was the greatest biotic crisis of the Phanerozoic. The extinction decimated both marine and terrestrial communities, and changed the evolutionary trajectory of multicellular life on the planet. The unique nature of the extinction’s aftermath has prompted attention from paleontologists seeking to understand the timing and pattern of the Triassic recovery. With this dissertation I have sought to shed additional light on the terrestrial side of the extinction by examining different patterns by which its survivors responded to the extinction.
Temnospondyl amphibians were one of the few tetrapod clades that were able to take advantage of the extinction to expand their diversity. In Chapter 1 I examine the relationship between taxonomic and ecological diversity of temnospondyls across the Permian-Triassic (P-Tr) boundary in the Karoo Basin of South Africa. Ecomorphological diversity, as implied by differences in cranial shape, was incorporated into the study by the use of a landmark-based geometric morphometric analysis. Both taxonomic diversity and cranial disparity were low during the Permian and increased across the Permian-Triassic boundary. Taxonomic diversity was stable through the Triassic, but disparity showed subsequent increases during the Olenekian and Anisian. Temnospondyls were restricted in size immediately following the extinction, but size range fully rebounded by the Olenekian. Tests of phylogenetic signal demonstrate that cranial shape was heavily influenced by phylogenetic relatedness, and the observed increases in disparity may be partly the result of decreases in the net relatedness of coeval Karoo stereospondylomorph temnospondyls in younger faunas. The increase in community-level taxonomic diversity for temnospondyls in the Karoo following the latest-Permian mass extinction was likely facilitated by an influx of distantly related and ecologically distinct species from other parts of Pangea.
In Chapter 2, I discuss the merits of different potential methods for quantifying rates of dispersal within clades. I then apply some of these methods to two very different scenarios, first the dispersal of crocodylians across oceanic barriers during the Late Cretaceous and Cenozoic, and second the dispersal of different groups of tetrapods across Pangea during the Permo-Triassic interval. For crocodylians, because they were dispersing across substantial geographic obstacles, I opted for a direct measurement approach utilizing the optimization of discrete dispersals onto phylogenies. I examined the history of crocodylian biogeography using both parsimony and maximum likelihood on three distinct topologies with several different methods for estimating branch lengths. Across all analyses, members of the clade Alligatoroidea consistently dispersed across oceanic barriers less frequently than did non-alligatoroids. This is consistent with the hypothesis that the greater degree of salt tolerance observed in extant crocodyloids and gavialoids played a role in shaping crocodylian biogeography. The phylogenetic and temporal distribution of high dispersal rates points to an acquisition of greater salt tolerance early in the history of Crocodyloidea and Gavialoidea, potentially near the base of Longirostres if the combined evidence topology is correct. Patterns observed for changes in dispersal rate within individual clades can be largely attributed to changes in global climate and continental configuration over their history.
The greater geographic ambiguity represented by the Permo-Triassic continental configuration makes a direct measurement approach inappropriate. For this study I instead opted for a proxy measurement approach, using the phylogenetic clustering of taxa within a community, measured using the Net Relatedness Index. I examined temporal changes in the phylogenetic clustering of five major tetrapod clades that span the Permian-Triassic boundary (Stereospondylomorpha, Parareptilia, Neodiapsida, Anomodontia, and Eutheriodontia) in order to examine patterns of extinction and origination through time, as well as rates of geographic dispersal. Some clades (Stereospondylomorpha, Parareptilia, and Neodiapsida) show evidence of phylogenetically selective extinction across the boundary, but this is not a universal pattern. Only one clade, Stereospondylomorpha, shows an unambiguous increase in dispersal rate following the mass extinction event. Other clades either show no change in dispersal rate, or have results that are mixed, depending on the parameters used in the analysis. These results show that stereospondylomorph temnospondyls were dispersing between geographical regions at increased rates during the Early Triassic, and this may explain much of their apparent increase in diversity following the latest-Permian mass extinction.
In Chapter 3, I perform a comparison between the timing of the Triassic recovery with that following the Cretaceous-Paleogene (K-Pg) mass extinction. Three terrestrial fossil-bearing successions were examined, the Lower Triassic Beaufort Group in South Africa and Cis-Ural succession in Russia, and the Paleocene faunas of the American northern Great Plains. A comparison of generic diversity of tetrapods through time for the post-extinction intervals reveals a temporal disparity between the length of terrestrial recovery after the latest-Permian and K-Pg extinctions. Both Permo-Triassic successions show a period of low taxonomic richness (4-5Myr) after the extinction event, followed by an eventual rise in richness. The North American K-Pg succession shows a different pattern, with an immediate rise in richness culminating in a plateau shortly after the extinction (1-3 Myr). This disparity in recovery times may result from prolonged deleterious environmental conditions following the P-Tr events, although several important differences exist between these sequential fossil assemblages that may be affecting the apparent speed of recovery.
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Santoso, Binarko. "Petrology of permian coal, Vasse Shelf, Perth Basin, Western Australia." Thesis, Curtin University, 1994. http://hdl.handle.net/20.500.11937/1466.
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The Early Permian coal samples for the study were obtained from the Vasse Shelf, southern Perth Basin, located approximately 200 km south- west of Perth. The selected coal samples for the study were also obtained from the Premier Sub-basin of the Collie Basin and the Irwin Sub-basin of the Perth Basin. The Early Permian coal measures are described as the Sue Coal Measures from the Vasse Shelf, the Ewington Coal Measures from the Premier Sub-basin and the coal measures from the Irwin sub-basin are described as the Irwin River Coal Measures.The Vasse Shelf coal is finely banded and the dominant lithotypes are dull and dull banded types, followed by bright banded and banded types, with minor bright types. The variation of dull and bright lithotypes represents fluctuating conditions of water table level during the growth of peat in the swamp. The maceral composition of the coal is predominantly composed of inertinite, followed by vitrinite and minor exinite and mineral matter. The coal is characterized by very low to medium semifusinite ratio and medium to high vitrinite content, supporting the deposition in anaerobic wet conditions with some degree of oxidation. The coal is classified as sub- bituminous to high volatile bituminous of the Australian classification. In terms of microlithotype group, the predominance of inertite over vitrite suggests the coal was formed under drier conditions with high degree of oxidation during its deposition. On the basis of the interpretations of lithotypes, macerals, microlithotypes and trace elements, the depositional environment of the coal is braided and meandering deltaic-river system without any brackish or marine influence.The maceral composition of the Collie coal predominantly consists of inertinite and vitrinite, with low exinite and mineral matter. The very low to low semifusinite ratio and low to medium vitrinite content of the coal indicate that the coal was formed under aerobic dry to wet conditions with some degree of oxidation. The coal is categorized as sub-bituminous according to the Australian classification. The domination of inertite and durite over vitrite and clarite contents in the coal reflects the deposition under drier conditions with fluctuations in the water table. On the basis of the interpretations of macerals, microlithotypes and trace elements distribution, the depositional environment of the coal is lacustrine, braided to meandering fluvial system, without the influence of any marine influx.The maceral composition of the Irwin River coal consists predominantly of vitrinite and inertinite, and minor exinite and mineral matter. The coal has very low semifusinite ratio and medium to high vitrinite content, suggesting the coal was deposited in anaerobic wet conditions with some degree of oxidation. The coal is classified as sub-bituminous of the Australian classification. The predominance of vitrite and clarite over inertite and durite contents in the coal indicates that the coal was formed in wetter conditions and in high water covers with a low degree of oxidation. Based on macerals and microlithotypes contents, the depositional environment of the coal is braided fluvial to deltaic, which is in accordance with the interpreted non- marine and mixed marine environment of deposition in the sub-basin.The petrological comparisons of Vasse Shelf, Collie and Irwin River coals show that the average vitrinite content of the Irwin River coal is highest (49.1%) and of the Collie coal is lowest (37.3%) of the three. The inertinite content is highest in Collie coal (49.1%), followed by Vasse Shelf (46.4%) and Irwin River (39.2%) coals. The exinite content is low in Irwin River coal (6.3%) as compared with Vasse Shelf (9.0°/,) and Collie (8.3%) coals. The mineral matter content is relatively low for all the three coals. The rank of the Vasse Shelf coal is high as compared with the Collie and Irwin River coals, either due to tectonic uplift after the deposition in post-Permian in the southern Perth Basin, or due to the average depth of burial over Vasse Shelf which is much greater than that of Collie and Irwin River coals.The comparisons of the coal from Western Australia with the selected Gondwana coals show that the predominance of inertinite over vitrinite occurs in the Western Australian coals (Vasse Shelf and Collie Basin). On the other hand, the Brazilian, eastern Australian, Indian and Western Australian (Irwin Sub-basin) coals are dominated by vitrinite over inertinite. The exinite content is highest in the Indian coals and lowest in the eastern Australian coals. The mineral matter content is highest in the Brazilian and Indian coals, and lowest in Western Australian (Vasse Shelf) and eastern Australian (Sydney Basin) coals. The rank of the coals ranges from sub- bituminous to medium volatile bituminous according to the Australian classification.
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Santoso, Binarko. "Petrology of permian coal, Vasse Shelf, Perth Basin, Western Australia." Curtin University of Technology, School of Applied Geology, 1994. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=14920.
Full textAbstract:
The Early Permian coal samples for the study were obtained from the Vasse Shelf, southern Perth Basin, located approximately 200 km south- west of Perth. The selected coal samples for the study were also obtained from the Premier Sub-basin of the Collie Basin and the Irwin Sub-basin of the Perth Basin. The Early Permian coal measures are described as the Sue Coal Measures from the Vasse Shelf, the Ewington Coal Measures from the Premier Sub-basin and the coal measures from the Irwin sub-basin are described as the Irwin River Coal Measures.The Vasse Shelf coal is finely banded and the dominant lithotypes are dull and dull banded types, followed by bright banded and banded types, with minor bright types. The variation of dull and bright lithotypes represents fluctuating conditions of water table level during the growth of peat in the swamp. The maceral composition of the coal is predominantly composed of inertinite, followed by vitrinite and minor exinite and mineral matter. The coal is characterized by very low to medium semifusinite ratio and medium to high vitrinite content, supporting the deposition in anaerobic wet conditions with some degree of oxidation. The coal is classified as sub- bituminous to high volatile bituminous of the Australian classification. In terms of microlithotype group, the predominance of inertite over vitrite suggests the coal was formed under drier conditions with high degree of oxidation during its deposition. On the basis of the interpretations of lithotypes, macerals, microlithotypes and trace elements, the depositional environment of the coal is braided and meandering deltaic-river system without any brackish or marine influence.The maceral composition of the Collie coal predominantly consists of inertinite and vitrinite, with low exinite and mineral matter. The very low to low semifusinite ratio and low to medium vitrinite content of ++<br>the coal indicate that the coal was formed under aerobic dry to wet conditions with some degree of oxidation. The coal is categorized as sub-bituminous according to the Australian classification. The domination of inertite and durite over vitrite and clarite contents in the coal reflects the deposition under drier conditions with fluctuations in the water table. On the basis of the interpretations of macerals, microlithotypes and trace elements distribution, the depositional environment of the coal is lacustrine, braided to meandering fluvial system, without the influence of any marine influx.The maceral composition of the Irwin River coal consists predominantly of vitrinite and inertinite, and minor exinite and mineral matter. The coal has very low semifusinite ratio and medium to high vitrinite content, suggesting the coal was deposited in anaerobic wet conditions with some degree of oxidation. The coal is classified as sub-bituminous of the Australian classification. The predominance of vitrite and clarite over inertite and durite contents in the coal indicates that the coal was formed in wetter conditions and in high water covers with a low degree of oxidation. Based on macerals and microlithotypes contents, the depositional environment of the coal is braided fluvial to deltaic, which is in accordance with the interpreted non- marine and mixed marine environment of deposition in the sub-basin.The petrological comparisons of Vasse Shelf, Collie and Irwin River coals show that the average vitrinite content of the Irwin River coal is highest (49.1%) and of the Collie coal is lowest (37.3%) of the three. The inertinite content is highest in Collie coal (49.1%), followed by Vasse Shelf (46.4%) and Irwin River (39.2%) coals. The exinite content is low in Irwin River coal (6.3%) as compared with Vasse Shelf (9.0°/,) and Collie (8.3%) coals. The mineral matter content ++<br>is relatively low for all the three coals. The rank of the Vasse Shelf coal is high as compared with the Collie and Irwin River coals, either due to tectonic uplift after the deposition in post-Permian in the southern Perth Basin, or due to the average depth of burial over Vasse Shelf which is much greater than that of Collie and Irwin River coals.The comparisons of the coal from Western Australia with the selected Gondwana coals show that the predominance of inertinite over vitrinite occurs in the Western Australian coals (Vasse Shelf and Collie Basin). On the other hand, the Brazilian, eastern Australian, Indian and Western Australian (Irwin Sub-basin) coals are dominated by vitrinite over inertinite. The exinite content is highest in the Indian coals and lowest in the eastern Australian coals. The mineral matter content is highest in the Brazilian and Indian coals, and lowest in Western Australian (Vasse Shelf) and eastern Australian (Sydney Basin) coals. The rank of the coals ranges from sub- bituminous to medium volatile bituminous according to the Australian classification.
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Granmayeh, Assadollah. "Petrology and provenance of Permian glaciogenic sediments of southern Australia /." Title page and table of contents only, 1994. http://web4.library.adelaide.edu.au/theses/09PH/09phg759.pdf.
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Rey, Kevin. "Thermophysiologie des thérapsides et changements climatiques du Permien et du Trias (300-200 Ma)." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1089/document.
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Les thérapsides se diversifient au cours du Permien et du Trias partout à la surface de la Pangée mais sans être épargné par la crise de la fin du Permien, extinction de masse la plus meurtrière de tous les temps. Ils représentent un groupe de transition entre les reptiles permiens et les premiers mammifères et sont le centre de plusieurs questions lié aux différences entre ces deux grands groupes. Cette thèse s'intéresse à la question de l'apparition et du développement de l'endothermie dans ce groupe, ainsi que les conditions environnementales présentes à cette époque. Pour répondre à ces questions, plusieurs espèces, provenant des grands groupes de vertébrés de l'époque (thérapsides, diapsides, parareptiles, stéréospondyles et dipneustes) ont été analysés pour leurs compositions en isotopes de l'oxygène et du carbone.Ces données ont permis de montrer que l'endothermie serait apparu au moins dans le groupe des Kannemeyeriiformes + Lystrosauridae ainsi que dans le groupe des Eucynodontia, deux lignés de thérapsides, la seconde ayant donnée les mammifères actuels. Temporellement, ces deux mises en place de l'endothermie se sont produites dans un intervalle de temps autour de la limite Permo-Trias, certainement avant celle-ci pour le groupe Kannemeyeriiformes + Lystrosauridae. Ce qu'il se passe climatiquement à cette période a été déterminé avec des espèces provenant exclusivement du bassin du Karoo en Afrique du Sud. D'après les résultats, à la fois les variations des isotopes de l'oxygène et du carbone se corrèlent avec celles observées dans le milieu marin et les valeurs obtenues à partir de matériel continental est tout autant pertinent à utiliser que celles provenant de matériel marin.Ces données appuient l'hypothèse d'un intense réchauffement et le quantifient à environ +16 °C au moment de la crise puis continua d'augmenter pendant le Trias Inférieur.Bien que les données ne permettent pas de le prouver, il est possible que l'endothermie ait permis à ces groupes de survivre ces variations de températures et de pouvoir se rediversifier par la suite<br>Therapsids diversified during the Permian and the Triassic all around the world on the supercontinent, Pangea, where they were not spared by the end-Permian crisis, the most destructive mass extinction of all time. The represent a transitional group between the Permian reptiles and the first mammals, and therefore are in the middle of several questions link to the difference between those two groups. This thesis focuses on the question of the emergence and development of the endothermy within this group, and the climate conditions of this period. To answer those questions, several species from the different groups of vertebrates (therapsids, diapsids, parareptiles, stereosponyls and lungfish) have been analyzed for their oxygen and carbon isotopes compositions.Such data showed that the endothermy seemed to appear within the group of Kannemeyeriiformes + Lystrosauridae as well as the Eucynodontia group, two therapsids groups with the latter being the ancestors of the extant mammals. Those two emergences of the endothermy occurred within a small timespan around the Permo-Triassic boundary, much more certainly before for the Kannemeyeriiformes + Lystrosauridae. What happened during this short period has been estimated with species from the Karoo Basin in South Africa only.According to the results, both variations in oxygen and carbon isotopes fit with those observed in marine data and therefore, values from continental material can be used, same as marine material.Those data support the hypothesis of an intense warming and quantify it to +16 °C during the end-Permian crisis and continue to increase during the Lower Permian.Even if the data don’t allow proving it, it is possible that the endothermy made those groups able to survive through such temperature variations and to diversify after
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Badaro, Victor Cezar Soficier. "Paleobiologia e contexto deposicional de microbialitos silicificados da formação Teresina (Permiano, Bacia do Paraná) no centro do Estado de São Paulo." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/44/44141/tde-13112013-155421/.
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Microbialitos são depósitos biossedimentares formados a partir do aprisionamento, aglutinação e/ou precipitação de sedimentos por intermédio de microbiotas bentônicas, geralmente cianobacterianas. Ocasionalmente, esses depósitos podem preservar suas microbiotas formadoras, especialmente quando apresentam silicificação precoce, antes da degradação total de sua matéria orgânica. Organismos alóctones, como formas planctônicas decantadas e outras trazidas pelas correntes também costumam se preservar, ainda que em número muito menor. Microbialitos são elementos comuns dos depósitos permianos do Grupo Passa Dois na Bacia do Paraná, onde ocorrem em diversos níveis e em uma área geográfica ampla, apresentando também diversidade e abundancia consideráveis, com alguns exemplos silicificados. Todavia, os microbialitos e microbiotas associadas do Grupo Passa Dois são pouco conhecidos. Este estudo consiste em uma análise de microbialitos silicificados e suas microbiotas dos afloramentos da Formação Teresina no Km 168 da Rodovia Presidente Castelo Branco, no sudoeste do Município de Porangaba, centro do Estado de São Paulo. Foram encontrados abundantes oncólitos e também raros representantes de uma nova categoria, denominada estromatoncólito. Esta nova categoria é caracterizada por uma estrutura interna oncolítica que serviu de base para um crescimento estromatolítico em seu topo. A presença destes dois morfotipos de microbialitos é indicativa da mudança no nível de base. A preservação de uma microbiota abundante e relativamente bem preservada indica que a silicificação ocorreu eodiageneticamente. A assembleia microfossilífera é formada quase exclusivamente por formas filamentosas, com raros palinomorfos e espículas de esponjas depositadas entre as tramas microbialíticas. A ausência de descrições detalhadas de microbialitos e microbiotas permianas da mesma unidade impossibilitou a comparação em grande escala, mas pode-se afirmar que os filamentos aqui descritos se assemelham taxonômica e tafonomicamente àqueles associados a estromatólitos da Formação Teresina em Angatuba, Estado de São Paulo. Isto encoraja a prospecção e descrição de novas ocorrências, visando melhor entendimento da paleobiologia e paleoambiente da Bacia do Paraná durante o Permiano.<br>Microbialites are biosedimentary deposits formed through the trapping, binding and/or precipitation of sediments by benthonic microbiotas, composed mainly of cyanobacteria. The microbialite-building organisms can be preserve within microbialites, especially when, in eodiagenesis, silicification occurs before the complete organic matter degradation. Planktonic and other allochthonous organisms decanted on microbial mats can also be preserved, although they occur in smaller numbers. Microbialites are common elements of the Permian Passa Dois Group of the Paraná Basin. They occur in several levels and over a large area, showing great diversity and abundance; silicified specimens also appear in these beds. The Passa Dois Group microbialites and associated microbiota were barely studied before and are, therefore, poorly known. The present study analyzes silicified microbialites and their associated microbiota in the outcrops of the Teresina Formation at the Km 168 of the Presidente Castelo Branco Highway, southwestern Porangaba County, center of São Paulo State. Abundant oncolites and rare specimens of a new category, designated stromatoncolites, were found. Stromatoncolites are characterized by an oncolitic internal structure which served as a foundation for a stromatolitic development on its top. The presence of these two kinds of microbialite morphotypes indicates base level changes. The well-preserved, abundant microbiota indicates that the silicification occurred during eodiagenesis. The microfossil assemblage is composed almost exclusively of filamentous forms, with rare palynomorphs and sponge spicules deposited within the microbialitic fabrics. The lack of detailed descriptions of other Permian microbialites and microbiotas of the Paraná Basin prevented major comparisons, but it can be said that the filaments here reported are taxonomically and taphonomically similar to those described for Teresina Formation at the Angatuba County, São Paulo State. Thus, the prospection and description of new occurrences are encouraged, in order to improve paleobiological and paleoenvironmental knowledge of the Paraná Basin during the Permian.
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Silva, Aurélio Fagundes. "Estudo da Bentonita associada com a Formação Irati na região de Aceguá, RS." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/133656.
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A presença de tonsteins e bentonitas dentro da Supersequência Gondwana I no setor sul da Bacia do Paraná não são incomuns e suas ocorrências estão documentadas, especialmente nas unidades Rio Bonito e Rio do Rasto. Embora fosse esperada a identificação de bentonita na Formação Irati devido ao seu posicionamento estratigráfico dentro do Permiano e por estar vinculada a um ambiente que preenche os requisitos para acumular e preservar os eventos de deposição de cinza vulcânica, não são conhecidos trabalhos sistemáticos voltados para a identificação da bentonita na Formação Irati do Rio Grande do Sul. A presença de níveis de bentonita na Formação Irati foi demonstrada a partir de trabalhos realizados no setor norte da Bacia do Paraná. Este artigo tem como objetivo identificar e apresentar argumentos mineralógicos e químicos que demonstram a existência de níveis de bentonitas inseridos na Formação Irati em afloramentos desta unidade situados a leste da cidade de Aceguá, sul do Rio Grande do Sul. Tratam-se de níveis com pequena espessura (em média 4 cm) e grande extensão lateral constituídos de argilitos maciços, com cores branco acinzentadas que em campo contrastam com os folhelhos que compõem a Formação Irati. Para o reconhecimento da bentonita, a técnica empregada na preparação das amostras viabilizou a realização de um estudo detalhado do comportamento mineralógico a partir da divisão das amostras numa fração fina (menor que 2μm) e numa fração maior que 0,025mm. As bentonitas do Irati se caracterizam por serem rochas bimodais compostas predominantemente por Camontmorilonita que formam a matriz fina da rocha onde estão dispersos cristais primários ou magmáticos com tamanho não superior a areia muito fina. Uma característica comum destes cristais e que atestam a origem vulcânica é o hábito idiomórfico, sem indícios de alteração ou de terem sido submetidos a processos de transporte sedimentar, em discordância ao que é observado com os minerais formadores da rocha encaixante representada pelo folhelho Irati. Entre os principais minerais primários identificados e representativos do ambiente vulcânico encontramse paramorfos de quartzo beta, feldspatos tipo sanidina, biotita, zircão, apatita e ilmenita. Baseando-se na geoquímica da rocha e na cristaloquímica da montmorilonita neoformada nos níveis de bentonita infere-se sobre a natureza do vulcanismo precursor. Ambas as metodologias apontam que neste período as cinzas vulcânicas que alcançaram a Bacia do Paraná foram oriundas de um vulcanismo com composição intermediária (andesítica) em concordância ao que é conhecido sobre as manifestações da Província Vulcânica Choiyoi Inferior, sincrônica com a sedimentação da Formação Irati na Bacia do Paraná. A comprovação obtida de que os níveis de argilitos identificados na seção estudada são bentonitas abre a perspectiva de novos estudos em outros campos da geologia, como a calibração da seção estratigráfica e de biozonas através de técnicas de datação absoluta com o uso de minerais, em especial os zircões. Os múltiplos níveis de bentonita identificados ao longo da seção também viabilizam estudos de avaliação do estilo e da história explosiva do vulcanismo, bem como permitirão melhorar as correlações entre diferentes exposições da formação Irati ao longo da Bacia do Paraná.<br>The presence of tonsteins and bentonite within Supersequence I in the southern sector of the Paraná Basin are not uncommon, and their occurrences have been documented, especially in the Rio Bonito and Rio do Rasto units. Although the identification of bentonite in the Irati Formation was expected, due to its stratigraphic position within the Permian and because it is linked to an environment that meets the requirements to accumulate and preserve volcanic ash deposition events, systematic studies aimed at identifying bentonite in the Irati Formation in Rio Grande do Sul are not known. The presence of bentonite levels in the Irati Formation was demonstrated from studies carried out in the northern sector of the Paraná Basin. This article aims to identify and present mineralogical and chemical arguments about the existence of bentonite levels included in the Irati Formation in outcrops of this unit located east of the city of Aceguá, southern Rio Grande do Sul. They are thin levels (on average 4 cm in thickness) and large lateral extension made up of massive claystones, of grayish white colors, which on the field stand out from the shales that compose the Irati Formation. In order to recognize the bentonite, the technique used in preparing the samples made it possible to conduct a detailed study of the mineralogical behavior based on the division of the samples into a fine fraction (less than 2 μm) and a fraction above 0.025 mm. The Irati bentonites are characterized by being bimodal rocks composed predominantly of Ca-montmorillonite which form the fine matrix of the rock where primary or magmatic crystals are dispersed, not larger than very fine sand. A common feature of these crystals that attest to the volcanic origin is the idiomorphic habit, with no signs of alteration or of having undergone sediment transport processes, unlike what is observed with the minerals forming the host rocks represented by the Irati shale. Among the main primary minerals identified and representative of the volcanic environment are the beta-quartz paramorphs, sanidine feldspars, biotite, zircon, apatite and ilmenite. Based on the rock geochemistry and the crystal chemistry of the neoformed montmorillonite in the bentonite levels, the nature of the precursor volcanism is inferred. Both methodologies indicate that in this period the volcanic ashes that reached the Paraná Basin were derived from volcanism of intermediate composition (andesitic) in agreement with what is known about the manifestations of the Lower Choiyoi Volcanic Province, synchronous with the sedimentation of the Irati Formation in the Paraná Basin. The obtained evidence that the claystones identified in the studied section are bentonites unfolds the perspective of new studies in other geology fields, such as the calibration of the stratigraphic section and biozones through absolute dating techniques with the use of minerals, especially zircons. The multiple levels of bentonite identified throughout the section also enable assessment studies of the explosive style and history of the volcanism, and will also improve the correlations between different exposures of the Irati Formation along the Paraná Basin.
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Mert-gauthier, Esra. "Modeling Permian Petroleum System Of Northeast Netherlands: Hydrocarbon Generation And Migration." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612508/index.pdf.
Full textAbstract:
Groningen Gas Field is located within the southern part of the South Permian Basin in
the northeast Netherlands. Since several wells have been producing from the
Carboniferous-Permian Petroleum System, the field is considered as mature for
hydrocarbon exploration. More detailed work is necessary to evaluate further
exploration and development opportunities. Thus, evaluation of the subsurface has been
carried out as part of the petroleum system concept by using the basin modeling.
In this study, seismic interpretation was performed by using 3-dimensional seismic and
borehole data with Petrel software in order to understand stratigraphy and structural
settings of the area. PetroMod basin analysis software has been used for 1-dimensional
and 2-dimensional basin modeling study by integrating interpreted geophysical,
geological and geochemical data.
Results show that the most recognized traps were formed during pre-Zechstein, and the
major generation-migration and accumulation of hydrocarbon commenced during
Middle Jurassic and continues to the present time. Since the timing of main hydrocarbon
generation varies spatially and has begun after trap formation, both early and late
migration enhances the potential of the porous Upper Rotliegend reservoirs. Prospective
hydrocarbon traps may occur in the southwestern regions of the basin due to shallower
depth of burial. On the other hand, all local structural highs that formed as a result of
salt movement create potential traps in the region.
32
Hogan, Ian. "Paleo-fluid migration and diagenesis in the Pennsylvanian-Permian Fountain Formation." Thesis, Colorado State University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1544780.
Full textAbstract:
<p> The Pennsylvanian-Permian Fountain Formation is an arkosic conglomeratic sandstone that was deposited in fluvial environments along the eastern flanks of the ancestral Rocky Mountains. The formation owes its pinkish red color to hematite cement that was precipitated early in its diagenetic history. Within the formation are whitened strata that crosscut laminations and facies boundaries, indicating that they are the result of a post depositional process. Whitened features are seen in core, indicating that they are not caused by modern weathering processes. Whitened strata similar to those present in the Fountain Formation are usually the result of the migration of reducing fluids. These fluids reduce and remove hematite cement leaving the fluid migration pathways whitened. Fluids that can cause large-scale reduction and removal of iron oxides include basinal aqueous brines and hydrocarbons. </p><p> Whitening within the Fountain Formation appears in a predictable stratigraphically-controlled manner and is most common in coarse channel sandstone facies that are adjacent to laterally continuous paleosol mudstones. The predictable distribution of whitened strata in outcrop suggests that fluid followed preferential pathways. Outcrop analysis indicates that these pathways are closely associated with thin paleosol mudstones and overbank deposits that seem to have focused the paleo-fluids that then flowed laterally along them in the coarser channel sandstones. Laterally continuous paleosol mudstones therefore may have played an important role in determining the spatial location of paleo-fluid migration pathways. Fluids moved through the formation as stringers that took up less than 15% of the total rock volume. </p><p> The Fountain Formation has a complex diagenetic history and has undergone multiple stages of cementation. A late stage dolomite cement contains organic matter, hydrocarbon inclusions, and is associated with bitumen. This cement is restricted to whitened strata and likely precipitated from a hydrocarbon-bearing fluid. The hydrocarbon-bearing fluid may have been the fluid that was responsible for whitening sections of the Fountain. Fluid inclusion data indicate that the precipitation of this cement took place after the formation was buried to a depth of at least 1.3km, which would have been during or after Laramide deformation. The presence of bitumen and hydrocarbon inclusions in strata that were not buried to hydrocarbon generating depths indicates that the hydrocarbon-bearing fluid likely migrated through the formation from deeper in the basin. </p><p> The amount of whitening in outcrop decreases in the northern study sites and may be related to a decrease in coarse channel sandstone facies. The lesser abundance of those facies at northern study sites may be because those sites were further from the sources for coarse material and were associated with lower energy environments. Although there is less whitened rock at the northern sites, the amount of fluid that passed through them may have been similar to the amount of fluid that passed through the southern sites. Evidence of this is a higher amount of feldspar alteration in whitened strata in the northern site, which may have been caused by more fluid flow per volume of rock because there were fewer coarse channel facies to act as conduits.</p>
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Becker, Andrew David. "Diagenesis of the Rotliegend Group (Lower Permian) : UK southern North Sea." Thesis, University of Birmingham, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.392626.
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McKeever, Patrick J. "Studies on the sedimentology and palaeoecology of the Permian of Scotland." Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335431.
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Goodall, Ian Geoffrey. "Sedimentology and diagenesis of the Edlington Formation (Upper Permian) of Teesside." Thesis, University of Reading, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328903.
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Alao, Abosede Olubukunola. "Basinfill of The Permian Tanqua depocentre, SW Karoo basin, South Africa." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20277.
Full textAbstract:
Thesis (MSc)--Stellenbosch University, 2012.<br>ENGLISH ABSTRACT: Basin subsidence analysis, employing the backstripping method, indicates that
fundamentally two different basin-generating mechanisms controlled Tanqua depocentre
development in SW Karoo Basin. The subsidence curves display initial dominantly
decelerating subsidence, suggesting an extensional and thermal control possibly in a strikeslip
setting during the depocentre formation; on the other hand, subsequent accelerating
subsidence with time suggests that the dominant control on the depocentre formation in SW
Karoo was flexure of the lithosphere. Based on these observations on the subsidence
curves, it is possible to infer that the first stage of positive inflexion (~ 290 Ma) is therefore
recognised as the first stage of Tanqua depocentre formation.
Petrographic study show that most of the studied sandstones of the Tanqua depocentre at
depth of ~ 7.5 Km were subjected to high pressure due to the overlying sediments. They are
tightly-packed as a result of grains adjustment made under such pressure which led also to
the development of sutured contacts. It is clear the high compaction i.e. grain deformation
and pressure solution occurred on the sediments; leading to total intergranular porosity
reduction of the quartz-rich sediments and dissolution of the mineral grains at intergranular
contacts under non-hydrostatic stress and subsequent re-precipitation in pore spaces.
Furthermore, siliciclastic cover in the Tanqua depocentre expanded from minimal values in
the early Triassic (Early to Late Anisian) and to a maximum in the middle Permian (Wordian
-Roadian); thereby accompanying a global falling trend in eustatic sea-level and favoured by
a compressional phase involving a regional shortening due to orogenic thrusting and positive
inflexions (denoting foreland basin formation). The estimate of sediment volume obtained in
this study for the Permian Period to a maximum in the middle Permian is therefore
consistent with published eustatic sea-level and stress regime data. In addition, this new
data are consistent with a diachronous cessation of marine incursion and closure of Tanqua depocentre, related to a compressional stress regime in Gondwana interior during the late
Palaeozoic.<br>AFRIKAANSE OPSOMMING: Die ontleding van komversakking met behulp van die terugstropingsmetode bring aan die lig
dat die ontwikkeling van die Tankwa-afsettingsentrum in die Suidwes-Karoo-kom hoofsaaklik
deur twee verskillende komvormende meganismes bepaal is. Die versakkingskurwes toon
aanvanklike, hoofsaaklik verlangsaamde versakking, wat daarop dui dat ekstensie- en
termiese beheer gedurende die vorming van die afsettingsentrum plaasgevind het,
waarskynlik in strekkingwaartse opset. Aan die ander kant toon daaropvolgende
versnellende versakking wat mettertyd plaasgevind het dat die vorming van die
afsettingsentrum in die Suidwes-Karoo eerder oorwegend deur kromming van die litosfeer
beheer is. Op grond van hierdie waarnemings met betrekking tot die versakkingskurwes, kan
mens aflei dat die eerste stadium van positiewe infleksie (~ 290 Ma) dus as die eerste
stadium van die vorming van die Tankwa-afsettingsentrum beskou kan word.
Petrografiese studie toon dat die meeste van die sandsteen wat van die Tankwaafsettingsentrum
bestudeer is, op diepte van ~ 7,5 Km aan hoë druk onderwerp was
weens die oorliggende sedimente. Die sandsteen is dig opmekaar as gevolg van die
korrelaanpassing wat onder sulke hoë druk plaasvind, wat op sy beurt ook tot die
ontwikkeling van kartelnaatkontakte aanleiding gegee het. Dit is duidelik dat die sediment
aan hoë verdigting, dit wil sê korrelvervorming en drukoplossing, onderwerp was, wat gelei
het tot algehele afname in interkorrelporeusheid by die kwartsryke sedimente; die
ontbinding van die mineraalkorrels in interkorrelkontaksones onder niehidrostatiese
spanning, en daaropvolgende herpresipitasie in poreuse ruimtes.
Voorts het silisiklastiese dekking in die Tankwa-afsettingsentrum toegeneem van minimale
waardes in die vroeë Triassiese tydperk (vroeë tot laat Anisiaanse tydperk) tot hoogtepunt
in die mid-Permiaanse tydperk (Wordiaans–Roadiaans). Dié ontwikkeling het
gepaardgegaan met algemene dalingstendens in die eustatiese seevlak, en is verder
aangehelp deur saamdrukkingsfase wat gekenmerk is deur regionale verkorting weens orogeniese druk en positiewe infleksies (wat met voorlandkomvorming saamhang). Die
geraamde sedimentvolume wat in hierdie studie vir die Permiaanse tydperk bepaal is, met
die hoogtepunt in die middel van dié tydperk, is dus in pas met gepubliseerde data oor die
eustatiese seevlak en spanningstoestand. Daarbenewens strook hierdie nuwe data met
diachroniese staking van mariene instroming en die afsluiting van die Tankwaafsettingsentrum
wat met spanningstoestand in die Gondwana-binneland gedurende die
laat Paleosoïkum verband hou.
37
Kearsey, Timothy. "Multi-proxy palaeoclimate reconstruction of the Permian-Triassic mass extinction event." Thesis, University of Plymouth, 2009. http://hdl.handle.net/10026.1/2096.
Full textAbstract:
The Permian/Triassic (P/Tr) boundary is widely assumed to have been a time of extreme environmental upheaval and change. In the terrestrial realm, a negative anomaly in 813C isotope values has been reported from organic carbon in Antarctica, Australia, India and Madagascar, and from marine carbonate in the Karoo Basin. However, these sections are all from southern palaeolatitudes. Analysis from the Permian-Triassic terrestrial sedimentary record of the South Urals, in Russia, comprising of many Aridisol and Vertisol horizons has revealed that, like the Southern Hemisphere, there is a dramatic change in paleosol morphology across the P/Tr boundary linked to a shift from meandering rivers to conglomeratic alluvial fans. Most of the paleosols include pedogenic carbonates at different stages of development, both above and below the P/Tr boundary. By the Triassic there is evidence of depressed water tables and increased seasonality. Analyses of the S13Qarba nd S18Ocarbsi gnatures of these pedogenic carbonates have revealed a number of negative excursions in 813Ccarabn d 5180carbin the Late Permian, including a negative excursion in the mid-Changhsingian, the first time such an event has been recorded in a terrestrial environment. Associated with this excursion are indicators of increasing extremes of climate, including pedogenic dolomite, which suggest a dramatic change in climate up to the P/Tr boundary. Equally, there is an increase in the range of precipitation, suggesting that what caused this mid-Changhsingian event also had a profound effect on the atmosphere. There is also evidence, in the form of the 818Ocaeßx, cursion, of a rise in temperaturej ust prior to the onset of the conglomeratic alluvial fan deposits, which mark the P/Tr boundary in Russia. Although in the Russian paleosols this excursion could be explained by a rise in the effect of seasonal rain or atmospheric temperature, estimates from unaltered brachiopods from the Italian Dolomites confirm that there is a rise in temperature and suggests that this is in the region of 7-8°C. These paleosols also record a dramatic rise in pCO2 in the Earliest Triassic similar to what has been recorded in stomatal records across this period suggesting a dramatic input of CO2 in to the atmosphere.
38
Hulett, Sam Rw. "Detrital Zircon Analysis of Permian Victoria Group Sandstones, Transantarctic Mountains, Antarctica." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1355867143.
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Li, Hongqi. "Paleobiology of Gigantopterids from the Upper Permian of Guizhou Province, China /." The Ohio State University, 1996. http://rave.ohiolink.edu/etdc/view?acc_num=osu148793635615897.
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Rader, Dennis Lawrence 1959. "The depositional environment of the Permian Scherrer Formation in southeastern Arizona." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/558045.
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Al-Langawi, Alham Jassim. "Dolomitization of Permian and Triassic shelf carbonates from the Oman Mountains." Thesis, University of Manchester, 1996. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.667747.
Full textAbstract:
This study is based on field, petrographic and geochemical investigations of the Hajar Supergroup autochthonous rocks (Ruus A1 Jibal Group, Musandam Peninsula, and Akhdar Group, Jebel Akhdar, Oman). The petrographic investigations were carried out by using transmission light microscope, scanning electron microscope, and cathodoluminescence. They were supplemented by geochemical analysis, using microprobe, X-ray diffraction, ion chromatography, atomic absorption, stable isotopes, and quantitative analysis by the scanning electron microscope. Field and petrographic evidence indicates that the rocks were deposited in shallow marine environments, particularly tidal flat, lagoon, reef, back-reef, and shoal environments that were part of the Arabian Platform during Permian and Triassic times. However they are almost entirely dolomitized and the rocks show different petrographic texures ranging from perfect preservation of the original texture by mimetic dolomitization to complete obliteration and destruction of the original limestone texture giving rise to inequicrystalline and equicrystalline fabrics. Dolomites were categorised on the basis of textural variations; crystal size, shape and impurity or inclusion distribution within crystals, and whether occurring as rock forming (replacive) or as cements. The dolomite types display variations in stoichiometry, ordering, and trace element concentrations, indicating differences in dolomitizing fluid chemistry and recrystallization stages that prevailed through time. Although dolomitization is pervasive, dolomites are petrographically and chemically immature. The petrographic and geochemical evidence strongly suggests that dolomitization began soon after deposition and that fluids close in composition to seawater were involved. Rocks showing preservation of allochems as well as marine cements by mimetic dolomite crystals, suggest that dolomitization was early (at shallow depth) with very active water circulation and occurred in a relatively short time. In some cases, there is evidence of meteoric water diagenesis which is clearly visible within dolomitized bioclasts and ooids that underwent a dissolution event and cementation prior to dolomitization. Petrographic and geochemical evidence from crystalline dolomites indicates several crystallisation events at shallow burial depths, under marine waters modified by increased temperature and mixing probably with evaporitic brines. Oxygen isotopes indicate baroque dolomite samples to have formed under shallow-burial, which were marked by elevated geothermal gradient, rather than under deep burial conditions. A recently proposed technique for analysing dolomites by the ion chromatography (Staudt et al., 1993) was found to give results which are nearly consistent with the rest of the petrographic and geochemical evidence, but stressed the idea of non-evaporitic related dolomitization. The only fluid capable of early dolomitization in the case of the Oman Mountains dolomites was warm seawater from the Tethys Ocean which was circulating in the subsurface.
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Zazzali, Sindbad. "Paléobiodiversité des ostracodes à la limite Permien moyen - Permien supérieur." Electronic Thesis or Diss., Paris 6, 2016. http://www.theses.fr/2016PA066111.
Full textAbstract:
Les ostracodes, microcrustacés (Arthropoda), sont relativement abondants dans les archives paléontologiques. Sensibles aux variations paléoenvironnementales, la composition des assemblages et leur diversité sont d’excellents marqueurs des changements qui affectent le benthos marin néritique. Leur diversité est connue pour être fortement affectée par la crise biologique marquant la limite Permien-Trias, mais leur histoire à la fin du Permien moyen reste peu documentée.Près de 10 Ma avant la limite Permien-Trias, à la fin du Permien moyen, un important épisode d’extinction intervient, préfigurant le déclin de la biodiversité à la fin du Paléozoïque.L’étude systématique des échantillons prélevés le long des coupes de Chaotian (province du Sichuan, Chine) et de Penglaitan (province du Guangxi, Chine) a permis l’identification de 115 espèces d’ostracodes, dont 7 nouvelles. Le travail réalisé sur ces coupes constitue la toute première étude des événements de la fin du Permien moyen et du début du Permien supérieur s’appuyant sur l’observation des assemblages d’ostracodes. L’état de conservation des carapaces d’ostracode, étudié lors de ce travail, enregistre les effets de la fin d’un épisode de régression et le début d’un épisode de transgression au sommet du Permien moyen à Penglaitan. Les résultats s’avèrent en accord avec les données lithologiques et paléontologiques présentées dans la littérature, un modèle de reconstitution paléoenvironnementale basé sur les données de préservation des ostracodes est proposé.Une analyse critique de la qualité du jeu de données a permis d’évaluer l’influence des biais d’échantillonnage sur la représentativité du matériel fossile dans les études sur la paléobiodiversité et la paléoécologie. Les biais peuvent être corrigés par un traitement méthodologique approprié qui rend valide la comparaison des données de biodiversité. La richesse générique et spécifique décroît sensiblement au cours du Capitanien. Le passage du Permien moyen au Permien supérieur enregistre une augmentation de la richesse spécifique, malgré une faible diversité générique. L’ordre des Palaeocopida apparait ici affecté par une baisse de diversité générique et spécifique au Wuchiapingien inférieur. Si ces résultats ne permettent pas pour l’iPermiannstant de caractériser un événement global de renouvellement des communautés d’ostracodes, l’étude de matériel fossile provenant d’autres régions du monde permettra de définir l’ampleur des phénomènes observés<br>Ostracods, microcrustaceans (Arthropoda), are quite abundant in the fossil record. Highly dependent to palaeoenvironmental conditions, their diversity and the assemblages’ composition are good indicators of changes affecting neritic marine benthos. Ostracods are known to be deeply affected by the Permian-Triassic crisis, but their history is poorly documented for the end of Middle Permian.About10 My before the Permian-Triassic boundary, the end of Middle Permian is characterized by a major extinction episode, which could be the first step of end-Palaeozoic biodiversity drop.Systematic study carried out on Chaotian section (Sichuan Province, P.R. China) and the Penglaitan section (Guangxi Province, P.R. China) samples allowed the identification of 115 species, including seven new species. The work carried out on these two sections provides the first study of end-Middle Permian extinction event, based on the observation of ostracod assemblages.Study of carapace preservation at Penglaitan section, highlighted the end of a regression phase and the beginning of a transgression phase at the top of Middle Permian. These results are relevant with lithologic and palaeontological data from literature. Thus, a palaeoenvironmental reconstruction model has been proposed, based on ostracod preservation data.An estimation of sampling bias consequences on fossil dataset representativeness in palaeobiodiversity and palaeoecology studies was realised. These biases could be corrected by an appropriate methodology allowing comparisons of biodiversity datum. Biodiversity data reveals a decrease of generic and specific richness during Capitanian. Specific richness increased passing the Middle-Upper Permian boundary. Palaeocopida order seems here affected by a generic and specific richness decline at basal Wuchiapingian. If these results do not allow for the time being to characterize a global ostracod turnover, further studies on material from other regions in the world will allow defining the extent of the observed phenomena
43
Sanders, Margaret McPherson. "GEOCHEMISTRYAND PETROGRAPHY OF THERMALLY METAMORPHOSED ANTARCTIC COAL: IMPLICATIONS FOR 13C -DEPLETED METHANE RELEASE." OpenSIUC, 2012. https://opensiuc.lib.siu.edu/theses/821.
Full textAbstract:
Large δ13C excursions present at the Permian-Triassic boundary are thought to indicate a considerable release of isotopically light carbon into the atmosphere (Retallack and Jahren, 2008). The largest of these excursions (-22.2 ‰) was measured in organic matter from Antarctica (Retallack and Jahren, 2008). Antarctic coals are known to be heavily intruded by Jurassic dikes and sills, and the δ13C values of the organic matter may have been influenced by later thermal alteration. In order to evaluate the influence of rank and maceral content on isotopic composition, a total of 335 samples described as Permian-age "coal" were obtained primarily from the United States Polar Rock Repository. Most of the organic matter from Permian coal seams in Antarctica has been extensively altered after burial by localized high heat flow and, in some cases, contact metamorphism associated with dikes and sills; this thermal alteration has likely changed the δ13C values of the organic matter. The rank of the samples prior to intrusion is estimated to be medium to high volatile bituminous. The majority of the samples analyzed (96%) have been altered to above low volatile bituminous rank based on vitrinite reflectance, most (83%) are semi- to meta-anthracites, and a few have been altered to anisotropic cokes. The samples do not follow the typical burial maturation geochemical track, as they are higher in volatile matter (%, daf) and O (%, dmmf), and lower in H (%, dmmf) than coals of the same rank that have undergone normal burial maturation. Carbon stable isotopic data indicate a weak correlation with coal rank as well as with the amount of pyrolitic carbon. Although the isotopically lightest samples measured in this study are located within what is interpreted to be the Permian-Triassic boundary, the effects of thermal alteration of organic matter on δ13C values must be considered in any interpretation of Permian-Triassic atmospheric conditions.
44
Forte, Giuseppa. "An Integrated Study on Late Cisuralian (Early Permian) Palaeoenvironments and Palaeoclimate of Southern Alps." Doctoral thesis, Università degli studi di Padova, 2018. http://hdl.handle.net/11577/3421836.
Full textAbstract:
The transition from ice-house to green-house conditions that characterized the Permian (289–252 million years ago) climate passed through several glacial and interglacial phases and an increase of aridity, which affected the palaeoequatorial regions. The causes behind this increase, which led to several important changes within the terrestrial ecosystems, are still poorly understood. During the Permian, extrabasinal floras, mainly composed of drought-tolerant plants such as conifers and other gymnosperms, started to spread and move into the lowlands, progressively replacing the hygrophytic lowland floras that characterized the Carboniferous peat-forming forests. These climate changes and terrestrial biotic turnover left an important imprint in the carbon stable isotopic composition of the atmospheric CO2, and consequently, of the terrestrial organic matter. However, the step-wise nature of the Permian palaeofloristic transition and the low-resolution of δ13C data on the terrestrial organic matter make it difficult to clearly reconstruct what happened to the Permian palaeoequatorial ecosystems. A palaeoenvironmental and palaeoclimate reconstruction of the Kungurian (Cisuralian, early Permian) Tregiovo Basin (NE-Italy) is here provided. A multidisciplinary study has been carried out, through which two sections of the Tregiovo Formation, respectively “Le Fraine” and Tregiovo village sections, have been investigated for sedimentology, geochemistry, palaeobotany and palynology. The taxonomical study on the two rich palaeobotanical assemblages of the “Le Fraine” section revealed a very diverse and abundant flora, composed of sphenophytes (Annularia), ginkgophytes (?Sphenobaiera), pteridosperms (Peltaspermum), conifers (e.g., Hermitia, Feysia, Quadrocladus, Dolomitia) and taxa with uncertain botanical affinity like taeniopterids (Taeniopteris), sphenopterids (Sphenopteris) and two incertae sedis “morphotypes”. The palaeobotanical and palynological study indicates a xerophytic character for the Tregiovo flora, mainly dominated by conifers and sphenopterids. A thorough taxonomical study on these two plant groups showed a remarkable diversity, which allowed to pre-date the first appearance of genus Dolomitia to be moved back to the Kungurian, and to identify a new sphenopterid species, Sphenopteris valentinii. Sedimentological studies from the two sections indicate a playa-lake environment alternating with stable lacustrine conditions. Lake phases are indicated by common microbial carbonates, whereas playa-lake phases are indicated by the occurrence of mud-cracks and tetrapod footprints. Stable isotopic analyses on bulk organic carbon and conifer coalified tissues from the two Tregiovo sections highlighted a distinct negative shift of the δ13C curve on the terrestrial organic carbon within the Tregiovo Formation, well-constrained to the middle Kungurian by radiometric data, that correlates very well with the negative shift recorded by other authors for the Kungurian. This work represents a contribution to the comprehension of the complex picture of Permian palaeoenvironments and palaeoclimate, filling a gap on the knowledge about the early Permian eastern palaeoequatorial ecosystems.<br>Il Permiano (289–252 milioni di anni) rappresenta un periodo di transizione da condizioni di ice-house a condizioni di green-house, avvenuto attraverso diverse fasi glaciali e interglaciali. Questo cambiamento è stato caratterizzato da un incremento di aridità che interessò le regioni paleoequatoriali della Pangea. Le cause principali di questo incremento e di altri importanti cambiamenti che hanno interessato gli ecosistemi terrestri sono ancora poco chiare. Nel Permiano, le flore che occupavano le aree al di fuori dei bacini, costituite soprattutto da conifere ed altre gimnosperme che meglio tollerano periodi di aridità, cominciarono a migrare all’interno dei bacini, rimpiazzando progressivamente le flore più igrofitiche che avevano caratterizzato le foreste pluviali Carbonifere. Tali cambiamenti, sia climatici che relativi al biota terrestre, lasciarono un’impronta considerevole sulla composizione isotopica della CO2 atmosferica, e di conseguenza, della materia organica terrestre. La natura discontinua della transizione paleofloristica Permiana e la scarsa risoluzione dei dati riguardanti il δ13C della materia organica terrestre, rendono difficile una chiara visione di quello che accadde agli ecosistemi Permiani paleoequatoriali. In questa ricerca, viene proposta una ricostruzione paleoclimatica e paleoambientale del bacino Kunguriano (Cisuraliano, Permiano inferiore) di Tregiovo (NE-Italia). Attraverso uno studio multidisciplinare, le due sezioni di “Le Fraine” e del villaggio, appartenenti alla Formazione Tregiovo, sono state investigate dal punto di vista sedimentologico, geochimico, paleobotanico e palinologico. Lo studio tassonomico sui due depositi a piante di “Le Fraine” ha rivelato una flora molto ricca e diversificata, composta da sfenofite (Annularia), ginkgofite (?Sphenobaiera), pteridosperme (Peltaspermum), conifere (e.g., Hermitia, Feysia, Quadrocladus, Dolomitia) e taxa con affinità incerta come taeniopteridi (Taeniopteris), sfenopteridi (Sphenopteris) e due morfotipi incertae sedis. Gli studi paleobotanico e palinologico indicano un carattere xerofitico per la flora di Tregiovo, dominata da conifere e sfenopteridi. L’approfondito studio tassonomico di questi due gruppi ha svelato una notevole diversità, ha permesso di retrodatare al Kunguriano la prima comparsa del genere Dolomitia, e ha consentito di identificare una nuova specie di sfenopteride, Sphenopteris valentinii. Gli studi sedimentologici su entrambe le sezioni hanno indicato un’alternanza tra condizioni di playa-lake e lacustri stabili. Le fasi di playa-lake sono indicate dalla presenza di mud-cracks ed impronte di tetrapodi, mentre quelle lacustri stabili sono indicate dalla presenza abbastanza comune di carbonati microbiali. Le analisi isotopiche sul carbonio stabile contenuto nel bulk e nei tessuti carbonificati provenienti dalle due sezioni, hanno evidenziato uno shift negativo della curva del δ13C della Formazione di Tregiovo. Quest’ultima, radiometricamente datata Kunguriano medio, è molto ben correlabile con lo shift negativo registrato da altri autori per il Kunguriano. Il presente lavoro rappresenta un notevole contributo alla comprensione del complesso, e tuttora incompleto, quadro degli ecosistemi e del clima Permiani, che va a colmare una lacuna nelle conoscenze riguardante gli ecosistemi paleoequatoriali Permiani della Pangea orientale.
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Shi, Xiao. "Fossil plants and environmental changes during the Permian-Triassic transition in Northwest China." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066588/document.
Full textAbstract:
La transition Permien – Trias est une période importante dans l’histoire de la Terre. L’extinction en masse de la fin du Permien est l’événement d’extinction le plus sévère de l’histoire de la vie sur Terre. Les études précédentes se sont principalement focalisées sur les événements biotiques en milieux océaniques. Récemment, de plus en plus de nouvelles recherches se sont développées sur les événements en milieu continental.Les bassins de Junggar et de Turpan en Chine du Nord, présentent une opportunité unique d’étudier la limite Permien – Trias en milieu continental grâce à de nombreux affleurements avec des séries continues.Les facies continentaux de la coupe de Dalongkou sur le flanc sud du bassin de Junggar et de la coupe de Taoshuyuan sur le flanc nord du basin de Turpan, ont été sélectionnés pour cette thèse. Les niveaux de l’intervalle de transition Permien – Trias correspondent aux formations “Wutonggou”, “Guodikeng” et “Jiucaiyuan”. D’abondants bois fossiles et empreintes de plantes ont été découverts dans ces coupes. Des logs sédimentaires détaillés ont été levés. L’approche utilisée ici est pluridisciplinaire pour reconstruire les Paléoenvironnements avec les bois fossiles et les plantes, les patrons des cernes croissance des bois et l’analyse des microfaciès sédimentaires.Cinq genres et six espèces de bois fossiles ont été découverts. Nous établissons trois nouveaux genres: Junggaropitys, Xinjiangoxylon et un nouveau genre (soumis pour publication). La courbe CSDM (Cumulative Sum of the Deviation from Mean diameter) a été utilisée pour analyser les cernes de croissance dans le but de déterminer les conditions d’intersaisonnalité et la longévité des feuilles des arbres. Nous avons déterminé que Junggaropitys dalongkouensis est une espèce à feuilles persistantes avec les feuilles à longévité de 3 à 6 ans; le XTT-C-4 gen. et sp. nov. est également à feuilles persistantes mais avec une longévité des feuilles de 3 à 15 ans.Septomedullopitys, Junggaropitys, Xinjiangoxylon et XTT-C-4 gen. nov. montrent tous un xylème secondaire de type Protophyllocladoxylon. En accord avec l’analyse paléobiogéographique, les bois de type Protophyllocladoxylon sont principalement distribués dans une zone climatique tempérée froide dans l’hémisphère sud, dans des zones climatiques variables dans l’hémisphère nord et dans la zone équatoriale au Paléozoïque supérieurLes résultats obtenus sur les bois fossiles montrent que le climat sur la région de Junggar devait être, à la limite Permien – Trias, chaud et humide, avec des températures et une humidité restant relativement stables.Il n’existe pas de période de forte sécheresse au Trias basal. Les méga-moussons de la Paléo-Téthys n’ont pas d’influence sur la région de Junggar sur la côte est de la Pangée aux latitudes moyennes. Combiné avec les résultats précédemment obtenus, nous montrons que le climat n’a pas subit de très fortes variations entre le Permien moyen et le Trias basal.L’analyse des plantes fossiles montre que le nombre de genres et d’espèces diminue progressivement de 26 genres et 53 espèces connues dans le Wuchiapingien à 10 genres et 15 espèces dans le Changhsingien et seulement 6 genres et 7 espèces dans l’Induen. La tendance à la réduction des assemblages floristiques dans les bassins de Junggar et Turpan semble montrer que le processus d’extinction est long et graduel et a débuté bien avant la limite Permien – Trias. Durant la période de récupération post-crise des flores, les lycopsides (Annalepis) et les fougères (Neocalamites et Pecopteris) ont joué un rôle d’espèces pionnières. Trois logs stratigraphiques ont été levés pour l’analyse des facies sédimentaires. Quatre principaux environnements de dépôts ont été reconnus dans la coupe de Dalongkou. Les séries de la Formation Wutonggou se sont déposées dans un environnement de rivières en tresse et de systèmes fluviaux éphémères ou d’étangs et de plaines alluviales<br>Permian-Triassic transition is an important period in the Earth’s history. The end-Permian mass extinction is the Earth's most severe known extinction event. Previous studies mainly focused on the biotic events in the ocean. Recently more and more researches on the terrestrial events during the Permian-Triassic transition attracted many attentions. The Junggar and Turpan basins of Northwest China command a unique and significant position in the study of terrestrial Permian-Triassic boundary (PTB) events as it contains well and continuously exposed PTB sections. The lithostratigraphy, biostratigraphy, and cyclostratigraphy have been well established in the two basins. The problem we are trying to solve, based on paleobotanical studies associated with sedimentological analyses, is the environmental changes during the Permian-Triassic transition in the research area.The terrestrial facies in the Dalongkou section on the south flank of Junggar Basin and the Taoshuyuan section on the north flank of Turpan Basin have been selected as the researching ones for this thesis. The Permian-Triassic transition strata have been included in the “Wutonggou”, “Guodikeng” and “Jiucaiyuan” formations. Abundant fossil woods and plant impressions have been discovered and collected in these sections. Detailed sedimentary logs of the sections were drawn. The approach that we adopt to recognize the environmental changes is the fossil wood and plant impression species, growth-ring pattern, and sedimentary facies analysis.Five genera and six species of fossil woods were discovered. We establish three new genera: Junggaropitys, Xinjiangoxylon and a new genus (submitted for publication). The CSDM (Cumulative Sum of the Deviation from Mean diameter) curve was used to analyse the growth rings to determine the intraseasonal conditions and leaf longevity patterns of the trees. We recognise that Junggaropitys dalongkouensis is evergreen, and the leaf longevity may be 3–6 years; XTT-C-4 gen. et sp. nov. is evergreen too, and the leaf longevity may be 3 to 15 years. Septomedullopitys, Junggaropitys, Xinjiangoxylon and XTT-C-4 gen. nov. all show a Protophyllocladoxylon-type secondary xylem. According to palaeobiogeographic analysis, the Protophyllocladoxylon-type woods distributed mainly in the cool temperate climate zone of the southern hemisphere, various climate zones of the northern hemisphere and equatorial zone during the Late Paleozoic. The results of fossil woods analysis obtained in this research shows the climate in the Junggar terrane around the PTB was warm and humid and the temperature and precipitation remained relatively stable. It did not exist a heavy dryness in the earliest Triassic. Meanwhile, the Palaeo-Tethys megamonsoons did not influence the Junggar terrane along the east coast of mid-latitude Pangaea. Combined with the previously reported fossil woods, it shows that the climate had no prominent change from the Middle Permian to earliest Triassic.Plant fossil analysis show that the numbers of plant genera and species gradually decreased from 26 genera and 53 species in the Wuchiapingian, to 10 genera and 15 species in the Changhsingian, and only 6 genera and 7 species in the Induan. The trend in the plant assemblage reduction in the Junggar and Turpan basins appears to be indicative of a long, protracted extinction process that may have started well before the Permian-Triassic boundary. During the plant recovery period, the lycopsids (Annalepis) and ferns (Neocalamites and Pecopteris) played roles of pioneer species during the plant recovery period<br>二叠-三叠纪之交是地球历史上的关键时期。发生在二叠纪末期的大灭绝事件是最严重的生物灭绝事件。前人对此次灭绝事件的研究主要集中于海洋生物的变化，近年来越来越多的研究开始关注于这一时期陆地生态系统的变化。 位于中国西北部的准噶尔盆地和吐鲁番盆地出露了完整的陆相二叠-三叠系界线附近地层，因此在这一研究方面具有独特的优势。前期研究中在这一个地区建立了良好的岩石地层，生物地层和旋回地层格架。本文将集中解决二叠-三叠纪之交研究区的环境变化问题。我们选择了位于准噶尔盆地南缘的大龙口剖面和吐鲁番盆地北缘的桃树园剖面，两个陆相地层剖面作为论文的研究对象。在这一区域，二叠-三叠系之交地层是由梧桐沟组，锅底坑组和韭菜园组组成。我们在大龙口剖面和桃树园剖面二叠-三叠系地层中发现了大量木化石和植物印模化石，对剖面绘制了详细的地层柱状图。我们鉴定了木化石和植物印模化石种属,木化石年轮类型，分析了沉积相变化，进而用来识别研究区的环境变化。 我们对所采集到的130块木化石进行了切片，通过生物显微镜对其解剖结构进行研究，共发现了木化石5属6种，包括建立的三个新属：Junggaropitys，Xinjiangoxylon和 XTT-C-4 gen. nov.（还在审稿中）。这三个属均具有内始式的初生木质部和Protophyllocladoxylon 型次生木质部，其中Junggaropitys具有同质但异细胞的髓部；Xinjiangoxylon拥有具薄壁细胞和分泌管的髓部；XTT-C-4 gen. nov.的髓部中具有独特的板状支撑结构。我们应用CSDM曲线（平均值偏差累计曲线）分析木化石的年轮用以识别其生长季的条件和叶的寿命。CSDM曲线分析表明Junggaropitys dalongkouensis为一种常绿植物，叶的寿命为3-6年；XTT-C-4 gen. et sp. nov.也为常绿植物，叶的寿命3-15年。Septomedullopitys, Junggaropitys, Xinjiangoxylon和XTT-C-4 gen. nov.四个属的木化石均展示出Protophyllocladoxylon型次生木质部。我们对晚古生代全球发现的具有Protophyllocladoxylon型次生木质部的木化石进行了生物古地理分析，我们发现，在晚古生代，具有Protophyllocladoxylon型次生木质部植物，在南半球仅分布在冷温带地区；而在北半球和赤道地区，其分布在不同的气候带。对木化石的分析显示准噶尔地块在二叠-三叠系界线附近古气候温暖湿润，温度和降雨量相对稳定；古特提斯洋巨季风没有影响到东岸的泛大陆中纬度地区。结合前人对这一地区其他木化石研究，我们认为研究区的古气候自中二叠世至早三叠世早期没有显著的变化。植物化石分析显示，植物种属由吴家坪期的26属53种逐渐减少到长兴期的10属15种再到早三叠世印度期的6属7种。在准噶尔盆地和吐鲁番盆地，二叠-三叠系之交，植物显示了一个长时间的逐渐灭绝的过程。通过对比白垩纪-第三纪植物灭绝事件和现代恶劣环境下植物恢复的实例，我们发现石松类（脊囊属）和蕨类（新芦木属和栉羊齿属）在植物复苏阶段扮演着先驱分子的角色。我们对大龙口剖面，桃树园A和C剖面进行了沉积相分析。在大龙口剖面我们识别出4个主要的沉积相。梧桐沟组上部主要由辫状河相，短暂的河流系统或湖和冲积平原相组成。锅底坑组为湖（或池塘）相和洪泛平原相沉积。韭菜园组主要由冲积平原和湖（或池塘）相沉积组成。在桃树园地区，梧桐沟组上部至锅底坑组底部的一套地层主要是湖（或池塘）相和洪泛平原相沉积。锅底坑组下部为一套辫状河沉积。而锅底坑组上部为冲积平原和湖（或池塘）相沉积。韭菜园组主要为辫状河和洪泛平原沉积。对碎屑岩的样品岩相学分析显示跨越二叠-三叠系界线，沉积物物源一致。其中火山碎屑物来源于多个火山源。大龙口剖面和桃树园剖面在界线附近沉积物的物源保持一致，这说明，这两个剖面在二叠-三叠系之交时期处于同一个盆地，而博格达山隆起晚于这一时间。灰岩样品指示了湖泊环境的沉积。二叠纪末期的植物灭绝降低了河岸的强度，增加了坡地的沉积物的提供，进而增加了河道中沉积物的卸载。这导致了研究区在吴家坪期和长兴期界线附近和早三叠世的两次沉积相的改变。
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Laurini, Carolina Rettondini. "Elasmobrânquios fósseis da Serra do Cadeado, Estado do Paraná (formação Rio do Rasto, permiano superior)." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/59/59139/tde-02102015-113833/.
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Os Chondrichthyes são gnastotomados não-tetrapodos com esqueleto interno essencialmente cartilaginoso. Fortes evidências sugerem que o grupo seja monofilético, estando dividido em dois grupos irmãos, Elasmobranchii e Holocephali. Os Chondrichthyes são componentes comuns das faunas aquáticas do Paleozóico, mas a preservação de esqueletos parciais é rara devido à natureza cartilaginosa do mesmo. Assim, o registro paleontológico é composto basicamente pelas mais partes mineralizadas, tais como dentes, dentículos dérmicos e espinhos de nadadeira. Dentes isolados de tubarões paleozóicos ocorrem em depósitos marinhos e continentais ao redor do mundo, sendo o registro mais antigo datado do Devoniano. Eles são compostos por tecidos mineralizados por hidroxiapatita, sendo constituídos por orto ou osteodentina e recobertos por enameloide. Os dentes cladodontes tratados aqui são provenientes de rochas do Permiano Superior (Formação Rio do Rasto, Bacia do Paraná), da Serra do Cadeado, norte do Estado do Paraná. Eles consistem no primeiro registro do grupo para a região, que possui importantes afloramentos de rochas paleozóicas e mesozóicas incluídas no contexto das unidades litoestratigráficas que compõem a Bacia do Paraná. Após a preparação mecânica e química do material, oito dentes praticamente completos e dez fragmentos, além de aproximadamente 100 dentículos dérmicos foram recuperados. Os dentes são osteodontes, multicuspidados, com as cúspides dispostas em linha e levemente comprimidas lábio-lingualmente. As coroas são ornamentadas com linhas bem marcadas. As bases são mesio-distalmente alongadas, com uma expansão lingual e numerosas perfurações. Levando-se em conta a problemática existente na classificação e atribuição de elementos esqueletais isolados a táxons extintos, tentou-se resolver a afinidade taxonômica dos espécimes tratados aqui até o nível taxonômico menos inclusivo possível, com base tanto na comparação da anatomia dentária com materiais depositados em coleção e dados disponíveis na literatura, quanto em variadas metodologias para a análise ultra-estrutural e histológica. O estudo comparativo dos dentes indica que o material pode ser atribuído a um Euselachii, relacionado à Hybodontiformes.<br>Isolated shark teeth are found worldwide in both marine and continental rocks dating as far back as the lower Devonian (Lochkovian), some 409 mya. They are important as palaeoenvironmental proxies and provide valuable biostratigraphic data for global correlation. Teeth are the main record of fossil chondrichthyans, because they are composed of mineralized tissues with hydroxyl-apatite. Most shark teeth are basically made up of enameloid and ortho- and/or osteodentine. The chondrichthyan teeth dealt here were collected in Late Permian rocks of the Serra do Cadeado area in north of Paraná, Brazil, in the litoestratigrafic context of the Rio do Rasto Formation (Paraná Basin). These remains represent the first record of Chondrichthyans in the area, where there are important outcrops of Paleozoic and Mesozoic rocks, providing a important paleontological window to the Late Permian of South America. Following mechanical preparation of the collected samples eight nearly complete teeth and ten tooth fragments were isolated. In addition, some 100 dermal denticles were recovered after chemical preparation. The teeth show a Cladodont morphology, including a mesio-distally elongated multicusped crown with a central main cusp. The cusp and cusplets are disposed in line, some of which are slightly labio-lingually compressed. The crowns are ornamented with strong, straight to slightly curved ridges. Tooth bases are mesiodistally elongated, and there is a lingual torus at the base. Numerous small foramina form a row right below the crown-base junction, while irregular, large pores perforate the basal surface of the tooth base. Various methodologies were used to study the specimens, including thin sections, scanning electronic microscopy and CT-scan. The crow and base morphology of these teeth are reminiscent of those ascribed to hibodontiform sharks.
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Costa, Victor Eduardo Pauliv Cardenes da. "Sphenacanthidae e xenacanthidae (chondrichthyes: elasmobranchii) da formação Rio do Rasto no estado do Paraná." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/72173.
Full textAbstract:
As estruturas com maior possibilidade de fossilização do esqueleto dos Chondrichthyes são aquelas mais mineralizadas, tais como dentes, escamas, espinhos cefálicos e de nadadeiras. Na Formação Rio do Rasto, os Chondrichthyes estão representados predominantemente por dentes e espinhos de nadadeiras. Na presente dissertação, foram estudados espécimes coletados em um afloramento do Membro Serrinha da Formação Rio do Rasto próximo ao quilômetro 20 da BR-153 no Município de Jacarezinho, Estado do Paraná, Brasil. O material corresponde a dois conjuntos, um representado por dois espinhos de nadadeira e o outro por vários dentes, todos depositados no Museu de Ciências Naturais do Setor de Ciências Biológicas da Universidade Federal do Paraná. No primeiro conjunto as características apresentadas pelos espinhos permitiram atribuí-los a uma nova espécie de Sphenacanthidae, enquanto que as características do segundo conjunto permitiram atribuir os dentes a uma nova espécie de Xenacanthidae. A associação fóssil na localidade-tipo e no mesmo horizonte estratigráfico da Formação Rio do Rasto indica que estas ocorrências de tubarões podem representar mais um registro de água doce para os xenacantídeos e esfenacantídeos.<br>The chondrichthian skeletal structures with greater potential of fossilization are the most mineralized such as teeth, scales, fin spines and cephalic spines. In the Rio do Rasto Formation the Chondrichthyes are represented by fin spines and teeth. The studied material came from an outcrop of Serrinha Member of the Rio do Rasto Formation, close to km 20, by the road BR-153 in the city of Jacarezinho, State of Paraná, Brazil. The studied material are two sets, one represented by two fin spines and the other by several teeth, all housed in the “Museu de Ciências Naturais do Setor de Ciências Biológicas da Universidade Federal do Paraná” - UFPR Natural Sciences Museum. In the first set, the features shown allow to ascribe the finspines to a new species of Sphenacanthidae, while the features of the second set allow to ascribe the teeth a new species of Xenacanthidae. The fossil association in the type locality and in the same stratigraphical horizon in the Rio do Rasto Formation indicates that these shark occurrences could represent another freshwater record for the xenacanthids and sphenacanthids.
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Sigurdsen, Trond. "The lower permian dissorophoid «doleserpeton» (temnospondyli), and the evolution of modern amphibians." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86879.
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The origin and evolution of modern amphibians is still a subject of controversy. The amphibamid temnospondyl Doleserpeton has often been suggested as a close relative of modern amphibians, but the skeletal morphology of this important taxon has never been fully described. In this thesis, a study of the skeletal anatomy of Doleserpeton is presented, and the interrelationships of dissorophoids are discussed. The relationships of modern amphibians and Paleozoic tetrapods are studied using phylogenetic analyses based on both Bayesian inference and parsimony. The skull of Doleserpeton is preserved in such detail that it allows the first description of the inner ear of an amphibamid temnospondyl. It is found to house a posteriorly positioned perilymphatic duct, a feature which is today restricted to amphibians. Evidence for the presence of a frog-like tympanic annulus is also described. During the studies of the limb skeleton of Doleserpeton, it was realized that important features of the forelimb of modern salamanders were misinterpreted in previous anatomical descriptions. Comparisons of the forelimbs of salientians (frogs), caudates (salamanders) and the Lower Jurassic caecilian Eocaecilia reveal important shared derived traits that are also found in Doleserpeton. Humeral evidence also indicates that saltation was an important part of the locomotion of the Lower Triassic salientian Triadobatrachus. Previous phylogenetic analyses are reexamined and numerous problems in previous character coding are revealed. An analysis of the new data collected suggests that modern amphibians may be a monophyletic group closely related to dissorophoid temnospondyls.<br>L'origine des amphibiens modernes reste un sujet de controverse. Doleserpeton a longtemps été suggéré comme un proche parent des lissamphibiens, mais l'anatomie de ce spécimen important n'avait toujours pas été complètement décrite. La présente thèse porte sur ce spécimen énigmatique en comparant sa morphologie aux amphibiens modernes et fossiles. Ceci nous nous informe sur les liens phylogénétiques entre les amphibiens modernes et ceux datant du Paléozoique en utilisant des analyses basées sur la parcimonie ainsi que sur l'inférence bayésienne. Les conditions de préservation du crâne de Doleserpeton sont telles qu'elles permettent la première description de l'oreille interne d'un membre de ce groupe. Ceci a permis de trouver la présence de conduits périlymphatiques, un trait généralement réservé aux lissamphibiens. Les structures tympaniques rappellent aussi celles des anoures. Ces nouvelles études comparatives ont permis de corriger certaines informations au sujet de l'anatomie des membres supérieurs des salamandres. Les comparaisons anatomiques entre les anoures, les salamandres et le fossile Eocecilia datant du Jurassique présentent de nombreux caractères communs qui permettent de mieux situer les caractéristiques de Doleserpeton. Les données provenant de l'observation de l'humérus ont permis d'établir que la saltation était présente chez Triadobatrachus. De nouvelles analyses phylogénétiques ont été effectuées afin de rectifier les stades des caractères utilisés. Ces nouvelles analyses suggèrent une descendance commune des amphibiens modernes à partir d'un groupe relié aux temnospondyles dissorophoides.
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Jenkins, Ian. "Cranial form and function in some Permian carnivorous synapsid (mammal-like) reptiles." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.407427.
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Hollingworth, N. T. J. "Palaeoecology of the Upper Permian Zechstein Cycle 1 reef of N.E. England." Thesis, Durham University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375050.
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