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1
Keatings, Kevin William. "The basis for ostracod shell chemistry in palaeoclimate reconstruction." Thesis, Kingston University, 1999. http://eprints.kingston.ac.uk/20651/.
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This project examined the trace-element and stable-isotope composition of non-marine ostracod shells and their use in Holocene palaeoclimate reconstruction, with particular reference to mid-latitude shallow carbonate lakes. Controls on the chemical composition of shells from such environments were studied. Results were used to test the application of ostracod shell chemistry data to palaeoclimate reconstruction. Selected techniques were applied to a high resolution study of Holocene lake marl sequence. The project investigated influences on shell chemistry during formation, sedimentary deposition and extraction. A core covering approximately 9,450 to 5,800 Cal. Yr BP was taken from Cunswick Tarn, Cumbria, yielding ostracod faunal and shell chemistry data used to produce a palaeoclimate interpretation for the early Holocene. This interpretation agreed with studies showing a warm, dry early Holocene and a cooler, wetter mid-Holocene. Seasonal sampling of water and ostracods at Cunswick Tarn provided a modern analogue for the core material. Species-specific fractionations of stable isotopes were similar to findings from ponds in Greywell, Hampshire. There were seasonal variations in the trace-element composition of shells, which may reflect: seasonal fluctuations; shell growth following initial calcification; and cleaning problems. Monthly sampling of water and ostracods was performed at carbonate ponds near Greywell. Species-specific fractionations of oxygen isotopes were observed. Compared to theoretical equilibrium calcite, all species exhibit [delta][sup]18 O values more positive than expected, while [delta][sup]13 C values equal equilibrium values. Variations in shell trace-element composition was greater than that of the water. This result may be related to animal physiology and the water’s low trace-element content. Ostracods collected from additional sites with elevated Mg/Ca[sub](water) ratios showed the best correlation between the Sr/Ca ratio of the water and the Sr/Ca of the shell. Effects of established cleaning techniques on shell chemistry were investigated. Whenever possible, only brush cleaning with deionised water should be used. Sodium hypochlorite is recommended for any further cleaning. An investigation of the effect of partial dissolution on shell chemistry demonstrated that even extremely degraded Cypretta brevisaepta shells have similar trace-element and stable-isotope ratios to unaltered shalls. However, dissolution may alter shell chemistry, and whenever possible, pristine shells should be used. Pseudocandona rostrata specimens from Greywell were grown in vitro. Adults had low weight with low M/Ca ratios. The Sr/Ca[sub](ostracod) ratios were negatively correlated with weight, while M/Ca[sub](ostracod) ratios were weakly positively correlated with M/Ca[sub](water), Sr/Ca[sub](water), and temperature. The research shows that a knowledge of the life-history and ecology of ostracods, together with the chemical signals recorded in their shells, can provide an effective tool for the interpretation of palaeoclimatic events.
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Ingram, Caroline S. "Ostracod palaeoecology and biogeochemistry of marine and estuarine interglacial deposits in North West Europe." Thesis, Bangor University, 1999. https://research.bangor.ac.uk/portal/en/theses/ostracod-palaeoecology-and-biogeochemistry-of-marine-and-estuarine-interglacial-deposits-in-north-west-europe(4cd7fd25-815b-4e1d-aebb-cada60a3d9b4).html.
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Ostracods were obtained from two cores in the southern North Sea area: the Sand Hole and Swarte Bank Formations of Tappin (1991) in BGS borehole 81/52A, cored from the Inner Silver Pit, southern North Sea, and a core from Shoeburyness in Essex, borehole S 1. The faunal assemblages in 131-181/52A were dominated by Sarsicytheridea punctillata, Elo/sonella concinna and Acanthocvthereis clunelmnensis. The assemblages recovered reflect a transition from glacio-marine conditions in the Swarte Bank Formation up into a cold-temperate marine environment in the Sand Hole Formation with deteriorating temperatures indicated at the top of the interval studied. In BHSI a freshwater to brackish transition occurred in the core, the freshwater section being dominated by Darwinula slevensoni and llyocypris spp., and the brackish section by Cyprideis torosa and C ytheromor pha fiiscata. The palaeoecology of the ostracod assemblages recovered is compared to other palaeoecological data from the same sections in each core and to ostracod data from other Hoxnian/l lolsteinian sites in north western Europe. These data are also discussed in the light of evidence indicating that there was a barrier across the southern North Sea when the sediments examined were deposited. Sarsicytheridea spp. and (yprideis terosa were used for trace element (Mg: Ca, Sr: Ca) and stable isotope (cS'"O, ö'3C) analyses. A calibration equation for the calculation of temperature from Mg: Ca ratio was successfully established from analysis of modern Sarsicytheridea. Modern Sr: Ca data could not be used to establish a calibration for salinity since there was too much scatter in the data. (' prideis torosa has been used for trace element and stable isotope work by other authors who have published relationships between ('yprideis and the water chemistry. Ostracods were also analysed down core to examine the changing ratios of Mg and Sr as a proxy for temperature and salinity changes in the I-loxnian of the southern North Sea. In BH81/52A, Mg: Ca data indicated a deterioration in temperature from 36.20 m to the top of the section studied of 9°C. Oxygen stable isotopic analyses from the same species, measured through the same core intervals, did not exhibit a trend, but their values were indicative of normal marine salinities. Carbon stable isotope analyses, performed at the same time as the oxygen analyses, indicate that there may have been high productivity in the region of deposition of the Sand Hole Formation, implying deposition in a region of freshwater influence. However, C/N analyses indicated that the sediments in the Inner Silver Pit were deposited under fully marine conditions. In III ISI, both the Mg: Ca and Sr: Ca data suggested that salinity had increased upcore. Ilowever, there was a lot of scatter in the data, indicating that the estuarine environment, under which the palaeoecology suggests the sediments were deposited, was a highly fluctuating one. These data compare favourably with previously published records. Published partition coefficients were used to compare the trace element data obtained to mean river and seawater values.
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White, Tom Samuel. "Late middle Pleistocene molluscan and ostracod successions and their relevance to the British Paleolithic record." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648393.
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Gaiger, Frances Jean. "Mid-Pleistocene Extinction of Deep-Sea Ostracoda?" Thesis, University of Canterbury. Geological Sciences, 2006. http://hdl.handle.net/10092/1349.
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A global extinction event has been documented in protozoan foraminifera in the late Pliocene to Pleistocene. The timing of the extinction event varied depending on location, however for Ocean Drilling Project Site 1125, disappearances occurred between 2.5 and 0.57 Ma, with the major decline approximately 1.1 Ma. In order to determine if this event affected benthic organisms other than protozoans, this study was undertaken to determine how podocopid ostracods (Crustacea) recovered Ocean Drilling Program Site 1125 responded. The present study was hindered by the small number of valves recovered; the fact that a large proportion of taxa found were undescribed and new to science; and the current state of taxonomic scheme that is under significant revision. These factors meant that a comprehensive comparison could not be achieved. Despite this, counts of ostracod valves and assessments of diversity from this study reveal a significant increase in both parameters from approximately 900-600 ka. Three possible causes were investigated to account for this increase, sediment type and sample size; affects of taphonomy, mainly dissolution; or an actual biotic 'event'. Statistical analyses showed that although sample size did have some effect, it was not the sole reason for the increase in ostracod numbers. Dissolution had an expected affect on the percentage of juveniles but no correlations were found with other sample characteristics. Sedimentation rate was investigated but this also proved unrelated. Therefore, it is suggested that the increase in total ostracod valves and diversity which occurs between 900 and 600 ka was in fact a natural, biotic 'event'. This preliminary evidence suggests that an oceanographic event that has negatively impacted on the foraminifers has had the reverse affect on the ostracod assemblage, in the sense that both population size and diversity increase during that time.
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Davies, Miles. "Ostracod assemblages and paloeoenvironments of a purported cold water section of the Mannum Formation, Devon Downs, South Australia /." Title page, contents and abstract only, 1995. http://web4.library.adelaide.edu.au/theses/09S.B/09s.bd2561.pdf.
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Thesis (B. Sc.(Hons.))--University of Adelaide, Dept. of Geology and Geophysics, 1996.Australian National Grid reference S1/54 Renmark sheet 1:250000. Includes bibliographical references (leaves 37-43).
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Mohibullah, Mohibullah. "The taxonomic, palaeoecologic and biogeographic importance of the Late Ordovician Laurentian ostracod fauna of the Girvan District, SW Scotland." Thesis, University of Leicester, 2012. http://hdl.handle.net/2381/11032.
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Ostracods form a numerically important component of certain Late Ordovician faunas of the Girvan district, southwest Scotland. Fifty-two ostracod taxa are identified, including twenty-three discussed in open nomenclature, and seventeen species that are considered as nomen dubia. The fauna reveals new and important data bearing on the biostratigraphic, palaeogeographic and palaeoecologic significance of the Girvan Lower Palaeozoic succession. Much of the Ordovician ostracod fauna of the Girvan district preserved in clastic deposits represents transported material. However, those ostracods from the early Katian Craighead Limestone Formation define shallow marine and open marine faunas respectively. The Girvan ostracods include many short-ranging species which are useful for inter-regional correlation of the Late Ordovician succession of Scotland and North America; these include Hippula ventrospinosa, Balticella deckeri, Eurychilina sunbloodensis and Baltonotella parsispinosa which characterize Sandbian age strata, and Kinnekullea comma which is typical for the Katian (anceps graptolite Biozone). Biogeographically most of the Girvan fauna is typically of North American aspect at the species level but from the early Katian onwards shows generic links with Baltica and Avalonia. The spatial and temporal distribution patterns of the Girvan Late Ordovician ostracod fauna are assessed in the context of the entire Late Ordovician Laurentian ostracod assemblage particularly for the Sandbian interval, where ostracod diversity was highest at species and genus level. Multivariate analysis demonstrates that geography had the strongest control on the global distribution of Ordovician benthic ostracods. Within Laurentia Sandbian ostracods show striking inter-basinal endemism at species level, ranging from 25% endemic in the Foxe Basin of the Franklin district, Canada to 75% in the Michigan basin. This pattern of endemism is common in other benthic groups such as brachiopods, and may indicate rapid speciation in microhabitats. Despite the strong overprint of local endemism, pan-continental faunal differences are noticed between the midcontinent and marginal Laurentian ostracod assemblages that are confirmed by multivariate analysis, and these allow the demarcation of a ‘Midcontinent’ and a southern ‘Marginal’ province for the Sandbian. Ostracod assemblages of the two provinces appear to have been controlled by physical parameters such as temperature and salinity which are related to water depth and latitude.
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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 observésOstracods, 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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Morais, Anderson Luiz Martins de. "Ostracodes (Crustacea, Ostracoda) das praias rochosas de Santa Catarina, Brasil." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/153380.
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Os ostracodes são microcrustáceos predominantemente bentônicos que deixaram rico registro fóssil, constituindo-se em importante ferramenta para a interpretação paleoambiental e bioestratigráfica. Estudos que tratam dos ostracodes recentes são de grande importância à Paleomicrontologia, pois muitos gêneros e até mesmo espécies do Cenozoico ainda são encontrados nos mares atuais. Diversos estudos versam sobre os Ostracoda na plataforma continental e talude superior no Brasil, mas são raras as pesquisas nas águas mais rasas do infralitoral. O principal objetivo deste estudo foi identificar e ilustrar a riqueza de espécies ao longo de uma ampla área litorânea do sul do Brasil, cuja costa é formada por numerosas pequenas praias guardadas por promontórios rochosos. Discutir aspectos relacionados à zoo- e à paleozoogeografia em especial dos elementos autóctones desta ostracofauna, além de introduzir a discussão sobre a fidelidade composicional entre associação viva e morta na área de estudo, estão entre os objetivos subsequentes.Dezoito famílias, 33 gêneros e 46 espécies foram identificados nesse estudo. A família Hemicytheridae é a mais representativa com 18 espécies, seguida por Cytheruridae com seis espécies. Duas espécies do gênero Xestoleberis Sars foram identificadas como prováveis novos táxons para Xestoleberididae. Preliminarmente, a fidelidade composicional é baixa, com maior riqueza na associação morta, bem como grande dominância e baixa riqueza na associação viva, um padrão esperado para zonas marinhas rasas como o infralitoral.Ostracoda are microcrustaceans with predominantly benthic habit which exhibit an abundant fossil record and constitute an important tool for paleoenvironmental and biostratigraphic studies. Research about recent ostracodes are extremely relevant to Paleomicrontology since many genera and even species from Cenozoic are still found nowadays. Several studies on Ostracoda from Brazil have focused on continental shelf and upper slope. The present work aims to identify and illustrate the species richness over a broad coastal area from southern Brazil, which coast is represented by numerous small sandy beaches guarded by rock promontories. Also, discuss zoo- and paleozoogeographic aspects, mainly related to autochthonous elements of this ostracofauna, and to introduce the discussion of compositional fidelity between living and dead ostracode assemblages, are among the subsequent objectives. Eighteen families, 33 genera and 46 species were identified. The family Hemicytheridae is the most representative with 18 species followed by Cytheruridae with six species. Two Xestoleberididae species herein identified are probably new taxa. A preliminary analysis showed low compositional fidelity with richness higher in death than in living assemblages. The living assemblage showed high dominance and low richness. This pattern is common for shallow marine zones such the infralittoral.
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Taha, Zardasht Ahmed. "The taxonomic, biogeographical, palaeogeographical and palaeoecological significance of the Late Ordovician Ostracod fauna of the Ellis Bay Formation, Anticosti Island, eastern Canada." Thesis, University of Leicester, 2018. http://hdl.handle.net/2381/42160.
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Ostracods form a significant component of the Late Ordovician fossil fauna of the Ellis Bay Formation, Anticosti Island, Canada. Sixty-two ostracod species are identified, belonging to 36 genera. These include 14 species described as new, and 13 species described in open nomenclature. The ostracod fauna reveals new and important data bearing on the biostratigraphical, palaeogeographical and palaeoecological significance of the Ellis Bay Formation. The stratigraphic distribution of the ostracods permits the recognition of four successive intervals: (A) the Longiscula subcylindrica Biozone, (B) the Eurychilina erugoface Biozone, (C) the Tetradella anticostiensis Biozone and (D) an Interregnum. Stratigraphical intervals A, B and D can be related to Copeland’s (1973) ostracod biozonation for the Ellis Bay Formation. Biozone C is equivalent to three of Copeland’s (1973) ostracod sub-zones. Presence/absence analysis of the ostracod distribution patterns in the Ellis Bay Formation identifies two palaeoecologically discrete assemblages: an open marine assemblage characterises most of the formation (lithostratigraphical members 1 to 6); whilst a lower diversity assemblage typifies the uppermost Member 7. Biogeographically, the Ellis Bay Formation ostracod fauna is typically North American (Laurentian), but also shares affinities with the Late Ordovician ostracod assemblages of palaeocontinental Baltica and Avalonia.
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Arenz, Alexis. "Behavioral Patterns of Blinded vs. Mock-blinded Male Individuals in the Presence of Females: Analysis of the Role of Eyes in Euphilomedes carcharodonta Mating." Scholarly Commons, 2018. https://scholarlycommons.pacific.edu/uop_etds/3108.
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Sexual dimorphism is exhibited throughout various organisms and takes an extensive variety of forms, although rarely does it take the form of eye-reduction within a population. This poses the question of whether this dimorphism arises due to sexual selection in order to increase reproductive success or rather from ecological selection as a result of sex-specific niche partitioning. In this case, we study an organism that displays a drastic form of sexual dimorphism, in that the males have large complex lateral eyes whereas the females lack eyes and merely have rudimentary lateral eye-spots. Euphilomedes carcharodonta is a small crustacean native to the coast of California. Studies on the dimorphism between these individuals have mainly been related to genetics and embryology. However, minimal studies have been performed questioning the evolutionary driving force behind their dimorphism. One study suggests that this driving force is ecological selection, more specifically, predator evasion as a result of the reproductive role hypothesis. In this study, we focus on sexual selection as a driving force and ask whether the eyes play a role in the ability of males to find mates. We blinded and mock-blinded male individuals, placed them in tank settings with females in the absence of predators, and observed their behavior. If sexual selection is involved in the eye development of males, we expected to see changes in male and/or female behavior in response to obstructing the vision of the males. We did not see changes in behavior of the males or the females. This leads us to conclude that the development of complex eyes in male Euphilomedes carcharodonta arises from ecological selection rather than sexual selection. With the previous work on predator evasion, these experiments and findings are the first to experimentally test the reproductive role hypothesis and are the beginning steps for further behavioral studies of these organisms and in discovering more about the unique dimorphism exhibited by Euphilomedes carcharodonta.
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Ferdinando, Darren. "Ostracode and foraminiferal taxonomy and palaeoecology of the Fossil Cliff Member of the Holmwood Shale, northern Perth Basin, Western Australia." University of Western Australia. Dept. of Geology and Geophysics, 2001. http://theses.library.uwa.edu.au/adt-WU2003.0019.
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The Sakmarian (Cisuralian, Permian) Fossil Cliff Member of the Holmwood Shale is situated in the northern Perth Basin, Western Australia, and consists of alternating beds of shale and silty calcarenite forming three parasequences. Within this member a diverse fauna of ostracodes and foraminifera are present. During the Cisuralian the northern Perth Basin formed part of the Gondwanan supercontinent and was linked to Greater India via an epeiric sea that opened to the north. The ostracode fauna is restricted to the calcareous beds of the member and consists of a diverse benthic fauna comprising 31 new species and 13 previously recorded species. Species from the Healdioidea, Bairdioidea, Youngielloidea, and Thlipsuroidea dominate the assemblage and suggest a normal-marine environment during the period represented by the calcareous beds, with an overall shallowing trend up the sequence. The fauna shows some similarity to faunas from the Tethyan deposits of North America and the Boreal deposits of Russia during the Late Carboniferous and Cisuralian. Twenty-eight species of foraminifera were recorded from the Fossil Cliff Member and underlying Holmwood Shale and comprise two distinct faunas, an agglutinated benthic foraminiferal fauna found within the shale beds and a calcareous benthic foraminiferal fauna present in the calcarenite units. The agglutinated foraminifera are inferred to represent deposition in dysoxic to suboxic (0.1-1.5 mL/LO2;), poorly circulated bottom waters below wave base. The calcareous foraminifera are inferred to represent deposition in normal-marine conditions. Both foraminiferal assemblages show a shallowing trend in their distribution that matches the trend identified in the ostracode fauna. Based upon the palaeoecology of the ostracode and foraminiferal faunas, the depositional environment for the Fossil Cliff Member is inferred to have been within shallow water in an epeiric basin during an overall marine regression that is overprinted by eustatic and isostatic oscillations resulting from deglaciation that occurred during the early Sakmarian (Cisuralian). These sea-level oscillations raised and lowered the oxic surface waters of the epeiric sea above and below the substrate resulting in a sparse agglutinated foraminiferal fauna or an abundant and diverse ostracode and calcareous foraminiferal fauna respectively.
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Utida, Giselle. "Fósseis em micritos quaternários da Serra da Bodoquena, Bonito-MS e sua aplicação em estudos paleoambientais." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/44/44141/tde-08062009-163642/.
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O município de Bonito e arredores em Mato Grosso do Sul apresentam atrações turísticas relacionadas a diversos tipos de depósitos carbonáticos quaternários, que formam cachoeiras, barragens naturais e tornam as águas de turbidez quase nula. A área está inserida no Parque Nacional da Serra da Bodoquena e na Reserva da Biosfera do Pantanal (UNESCO). As tufas calcárias são rochas porosas formadas pela precipitação do carbonato de cálcio em água doce e podem conter diversos tipos de fósseis. Apresentam-se sob a forma de cachoeiras, barragens e sedimentos lacustres que formam depósitos micríticos inconsolidados, descritos dentro da Formação Xaraiés. Os micritos são extensos e relativamente espessos em toda a região. Contudo, a maior parte das ocorrências está intemperizada, parcialmente erodida e distribuída em áreas limitadas. O presente estudo foca a caracterização paleontológica, granulométrica e geoquímica (elementos maiores, menores, traços e isótopos de carbono e oxigênio), através de levantamento de detalhe dos micritos da área da Mineração Calcário Xaraés, em Bonito (MS). As amostras foram obtidas por furo de trado, coleta de amostras superficiais e de bloco decimétrico orientado para estudo tafonômico, complementado com investigação de campo e amostragem de algumas áreas na Serra da Bodoquena, Pantanal e Corumbá. Os micritos da Mineração Calcário Xaraés, são depósitos lacustres e podem ser descritos em três eventos: 1: base afossilífera, oncólitos, argilominerais e dados isotópicos marcam um período de maior umidade; 2: ostracodes, algas caráceas e gastrópodes fósseis que colonizaram este estágio e a baixa variação dos dados isotópicos sugerem um período estável; 3: gastrópodes de água doce resistentes a ressecamento colonizaram esta etapa, em associação com os dados isotópicos sugerem processos alternados de evaporação e umidade. O topo da seção estudada é marcada por evaporação total da água do lago, morte em massa do gastrópode Biomphalaria e instalação do gastrópode Idiopyrgus. A ausência de estruturas sedimentares, orientação, seleção e fragmentação dos bioclastos e o empacotamento fraco a disperso e feições de alteração dos bioclastos por tempo de exposição na interface água-sedimento denotam condições estáticas do ambiente durante o processo final de deposição. Estas características também sugerem abastecimento do lago por águas subterrâneas, pois produzem menor taxa de alteração dos bioclastos e manutenção das condições químicas da água, como demonstrado pela homogeneidade dos dados geoquímicos. Outros depósitos estudados de micritos também apresentam resultados semelhantes. Há forte presença de indivíduos do gênero Biomphalaria e da Família Hydrobiidae nos depósitos. Dados de campo mostram os depósitos de tufas calcárias na região com extensão maior que as registradas, ocorrendo principalmente próximos aos leitos dos rios atuais, que os dissolvem nos períodos chuvosos. Os depósitos de tufas calcárias da Serra da Bodoquena, principalmente os micríticos, provavelmente foram formados nos últimos 10.000 anos, indicando período mais quente e seco que o atual. Os últimos 2.700 na região podem ser caracterizados por aumento da umidade, extinção dos depósitos micríticos e instalação dos depósitos de tufas de cachoeira e barragens.Bonito town and surrounding areas in Mato Grosso do Sul state are tourist attractions related with many quaternary carbonate deposits which form waterfalls, dams and render almost zero turbidity waters. That area is part of the National Park of Bodoquena Range and Pantanal Biosphere Reserve (UNESCO). Calcareous tufa are porous rocks formed by calcium carbonate laid down in freshwaters containg a great variety of fossils. They were presented in form of waterfalls, dams and lacustrine sediments, forming unconsolidated micritic deposits, being part of the Xaraés Formation. Micritic deposits are extensive and thick in whole area. Most of the deposits are weathered, partly eroded and distributed in restricted areas. The present study focuses on paleontological, granulometric, and geochemical (major, minor and trace elements, carbon and oxygen isotopes) data. The micritic deposits of Calcário Xaraés Mine in Bonito (MS) are detailed studied. Samples were obtained by auger drilling, also in outcrops area and one orientated centimetric indeformed block for taphomic study. The research was complemented with field study and sampling in the Bodoquena Range, Pantanal and Corumbá. Calcário Xaraés Mine micrites are lacustrine deposits. We described through three events: 1: their base does not contain fossils, but bears oncoids, clayminerals. Isotope data point to a wetter period, 2: ostracods, charophytes and gastropods fossils colonized this episode and homogeneity of isotope data suggest a stable event, 3: freshwater gastropods endured scarce water conditions so colonized the area. The isotope data then was varied suggesting alternated periods of evaporation and humidity. Total water lake evaporation resulted in the mass death of the Biomphalaria gastropod and consequent with diffusion of Idiopyrgus gastropod. Absence of sedimentary structures, bioclastic orientation, selection and fragmentation, weak to dispersal packing bioclast and bioclastic alteration features, are indications of long durantion in the water-sediment interface. These features suggest environmental static conditions during the final deposition. These features also suggest groundwater supplies to the lake, leading to less bioclastic alteration, and maintaing chemical water conditions, such as homogeneity of geochemical data. Other studied micritic deposits show almost the same results. There is strong presence of gastropod Biomphalaria and Hydrobiidae Family on these deposits. Field data show calcareous tufa deposits with an extension larger than the studied area, occurring mainly next to the rivers, which dissolve micritic in the rainy period. Bodoquena Range calcareous tufa deposits, mainly micritic sediments, probably were formed in the last 10.000 years, indicating a hotter and drier period than nowadays. The last 2.700 years in this region can be characterized by humidity increase, micritic deposits extinctions and installation of waterfalls and dams tufa depositions.
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Sartori, Lisandra Aparecida Alves. "Variações faunísticas ((Ostracoda) no testemunho G-77, quaternário tardio da Bacia de Campos, Brasil." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/38630.
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Estudos recentes têm demonstrado significativas variações na composição da fauna de ostracodes batiais decorrentes de mudanças climáticas. Visando verificar como esses eventos afetaram a ostracofauna batial da bacia de Campos foram analisadas 15 amostras provenientes de um testemunho a pistão recuperado a 1.287 m de lâmina de água. Espécies alóctones e autóctones foram identificadas sendo apenas as últimas estudadas. A idade das amostras foi obtida com base na análise de isótopos estáveis de oxigênio em testas do foraminífero planctônico Globigerinoides ruber, e os resultados comparados com dados do SPECMAP (Spectral Mapping Project). Foram identificadas 50 espécies autóctones distribuídas em 26 gêneros e 17 famílias. Os gêneros Krithe e Cytheropteron foram os mais diversificados (sete e cinco espécies, respectivamente). A família mais diversificada foi Cytheruridae, corroborando outros estudos paleoceanográficos. Foi estabelecida a idade de 42 ka para a base e 200 anos para o topo do testemunho. A análise de agrupamento por similaridade de Jaccard dividiu as amostras em dois grupos separados na amostra 12 (17,3 ka), no limite Holoceno-Último Máximo Glacial. A diversidade oscilou significativamente entre períodos glaciais e interglaciais, sendo menor no primeiro (3,0 nats/ind-1) e maior no último (3,4 nat/ind-1). Foi observado o predomínio de Argilloecia e Cytheropteron durante a deglaciação, Saida no interglacial, Apatihowella no UMG, Krithe no glacial e Macropyxis durante o UMG e glacial. Xestoleberis, por sua vez, ocorreu com diversidade relativamente constante ao longo de todo o testemunho. A distância taxonômica entre as espécies que ocorrem no glacial e interglacial se mostrou dentro dos limites esperados, com pequena proximidade entre os limites superiores e inferiores, respectivamente. A fauna de ostracodes da Bacia de Campos respondeu às variações climáticas ocorridas no Quaternário, o que reforça seu grande potencial como indicadora de mudanças paleoceanográficas.Present studies have demonstrated significative changes in the composition of bathyal ostracode fauna caused by climatic events. With the objective of assess the influence of these events on the bathyal ostracodes from Campos Basin, 15 samples from a piston core taken at 1,287 m water depth were studied. Both allochthonous and autochthonous species were identified, however, only the latter were analyzed. The age of the samples was determined based on oxygen stable isotope data from tests of the planktonic foraminifer Globigerinoides ruber and compared to SPECMAP (Spectral Mapping Project) ones. Fifty autochthonous species belonging to 26 genera and 17 families were identified. The genera Krithe and Cytheropteron were the more diversified (seven and five species, respectively), while Cytheruridae was the most diversified family, supporting other paleoceanographic studies. The core bottom was dated as 42 ka, and the top 200 years. The Jaccard similarity grouping analysis shared the samples into two groups being the sample 12 (17.3 ka) the limit between them, which corresponds to the Holocene-Last Glacial Maximum transition. The diversity varied significantly between glacial and interglacial periods, being lower in the former (3.0 nats/ind-1) and higher in the latter (3.4 nat/ind-1). The predominance of Argilloecia and Cytheropteron during the deglacial, Saida during the interglacial, Apatihowella during LGM, Krithe on glacial, and Macropyxis during the glacial and LMG was recorded. Xestoleberis was registered with steady diversity values along the core. The taxonomic distances between the species in the glacial and interglacial presented ordinary values, with small distance between the upper and lower limits, respectively. The ostracode faunas from Campos Basin responded to the Quaternary climatic events, reinforcing the use of deep-sea ostracodes changes as a paleoceanographic proxy.
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Machado, Cláudia Pinto. "(Paleo)zoogeografia dos ostracodes holocênicos das regiões leste e nordeste da plataforma continental brasileira." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/132777.
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Os estudos com ostracodes recentes e sub-recentes da plataforma continental do Brasil têmse concentrado, até o momento, principalmente nas plataformas equatorial e sul/sudeste. A região leste/nordeste, localizada entre estas duas áreas, aqui considerada como a área entre o Cabo de São Roque (RN) e Cabo Frio (RJ), não foi devidamente estudada, apresentando diversas lacunas do ponto de vista taxonômico e zoogeográfico. Visando suprir esta carência, o presente trabalho tem por objetivo o estudo da taxonomia dos ostracodes das plataformas leste e nordeste do Brasil, buscando a integração destas informações à compreensão da sua origem e distribuição zoogeográfica. O material de estudo incluiu 102 amostras sedimentológicas, coletadas por amostradores tipo Phipps ou Van Veen, provenientes do projeto REMAC (Reconhecimento Global da Margem Continental), tratos 4 e 7, em profundidades que variaram de 12 a 110 m. Os ostracodes recuperados das amostras foram acondicionados em lâminas de células múltiplas através das técnicas usuais para a preparação e o estudo de carapaças e valvas de ostracodes. Foram reconhecidas 128 espécies não se descartando a possibilidade de espécies novas. A área de estudo é caracterizada por possuir 34% de espécies típicas de águas temperadas, 42% de águas quentes e 5% de espécies euritérmicas. As 19% restantes não puderam ser avaliadas por apresentarem baixa ocorrência. A comparação da distribuição da fauna de águas temperadas com a de águas quentes permitiu a identificação plena dos limites da zona de transição proposta por Coimbra & Ornellas (1989) e modificada por Coimbra et al. (1995). O levantamento total da fauna da porção setentrional da plataforma continental brasileira (entre o Cabo Orange e Cabo Frio) reconheceu 213 espécies, sendo 32% endêmicas. A análise da distribuição da ostracofauna permitiu o reconhecimento de cinco padrões de distribuição da fauna, todos aparentemente limitados por fatores ambientais. Baseado no grau de endemismo, na distribuição da fauna e nas características ambientais da área de estudo, foi proposta uma nova província zoogeográfica, a Província Brasileira, cujo limite sul está em torno das latitudes 15º/16ºS. O limite norte continua em aberto devido à inexistência de trabalhos para Ostracoda na região situada entre a Guiana Francesa e Guiana. Os representantes fósseis da Província Brasileira contam com espécies que ocorrem desde o Terciário. A ostracofauna não endêmica provavelmente teve seu sucesso de dispersão facilitado pelas variações eustáticas que ocorreram ao longo do Neógeno e Quaternário. A presença de massas d’água mais quentes é a característica que melhor explica a distribuição atual dos ostracodes marinhos rasos da porção setentrional da plataforma continental brasileira.The studies concerning Recent and Sub-Recent ostracodes from the Brazilian continental shelf have been so far devoted mainly to the Equatorial and to the South/Southeast shelves. The region between these two shelves, consisting of the area between Cabo de São Roque (RN) and Cabo Frio (RJ), has not been appropriately studied and displays several gaps in Ostracoda taxonomy and zoogeography. In order to improve these deficiencies, the present study approaches the taxonomy of ostracodes form the East and the Northeast Brazilian shelves, aiming at the understanding of its origin and zoogeographical distribution. The 102 samples on which this study is based on were collected by Phillips and Van Veen grabs samplers from Remac Project (legs 4 and 7), at depths that vary from 12 m to 110 m. One hundred twenty-eigth species have been identified, some of which may be new. 34% of the species found in the study area are typical of temperate water, 42% of warm water and 5% are eurythermal. The remaining 13% of the species could not be evaluated due to insufficient occurrence. The comparison of the distribution of the temperate water fauna with the warm water fauna allowed the full identification of the limits of the transition area proposed by Coimbra & Ornellas (1989) and modified by Coimbra et al. (1995). The complete review of the fauna of the northern portion of the Brazilian Continental Shelf from Cabo Orange (AM) to Cabo Frio (RJ) recognized 213 species, 32% of which are endemic. The analysis of the distribution of the ostracode fauna allowed the identification of five distribution patterns, all of which are apparently limited by ambiental factors. A new zoogeographical province (the Brazilian Province) has been proposed. Its southern limit is located in the 15º/16º S latitude. The northern limit remains indeterminate, due to the inexistence of ostracode studies in the region from French Guyana to Guyana. Fossil representatives for the Brazilian Province display specimens that are as old as the Tertiary. The non-endemic ostracode fauna probably has its dispersion success rendered easier by the sea-level fluctuations that occurred in the Neogene and Quaternary. The presence of warmer water masses is the factor that more appropriately explains the present distribution of shallow marine ostracodes in the northern portion of the Brazilian continental shelf.
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Manica, Raquel de Mattos. "Ostracodes eomiocênicos da perfuração 2-RSS-1, Bacia de Pelotas, Atlântico Sudoeste." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/133201.
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Ostracodes são microcrustáceos que possuem uma carapaça bivalve constituída por quitina e carbonato de cálcio, que vivem em ambientes marinhos e não-marinhos. São amplamente utilizados em estudos paleoceanográficos e paleoclimáticos, sendo bons indicadores batimétricos, de salinidade e de temperatura. Nas bacias brasileiras, os ostracodes têm larga aplicação bioestratigráfica, especialmente em intervalos não marinhos cretáceos. Por sua vez, os ostracodes marinhos têm se destacado pelos bons resultados paleoceanográficos em bacias marginais, entre elas a Bacia de Pelotas. Este trabalho propõe novas espécies eomiocênicas da família Cytherellidae e do gênero Actinocythereis. A partir do estudo taxonômico discutem-se implicações paleozoogeográficas de eventos como o estabelecimento da Corrente Circumpolar Antártica e da Corrente das Malvinas, cuja ação influenciou a dispersão dos ostracodes ora registrados na Bacia de Pelotas. A partir da análise do intervalo testemunhado 1300 m-1318 m do poço offshore 2-RSS-1 coletado pela Petrobras na década de 1970, são registradas cinco espécies da família Cytherellidae, duas das quais aqui descritas, como segue: Inversacytherella atlantica sp. nov., Cytherella pelotensis sp. nov., Cytherella sp. 1, Cytherella sp. 2 e Grammcythella? sp. É também proposta Actinocythereis imbeensis sp. nov., a qual constitui a segunda espécie descrita para o gênero no Brasil. São ainda registradas, Krithe coimbrai, Krithe gnoma e Henryhowella kempfi, atribuídas em trabalhos anteriores ao estabelecimento de massas de água frias na costa Sul-Brasileira. As ocorrências de Inversacytherella e Grammcythella, por sua vez, constituem evidências para o intercâmbio faunístico entre a América e a Oceania decorrentes de mudanças hidrológicas no Oceano Austral ao longo do Neogeno. O Apêndice 1 apresenta a lista e a documentação fotográfica das demais espécies registradas.Ostracods are microcrustaceans with a bivalve carapace composed by chitin and calcium carbonate, living in both marine and non-marine environments. They are broadly used in paleoceanographic and paleoclimatic studies as indicators of bathymetry, salinity and temperature. In the Brazilian sedimentary basins the ostracodes have biostratigraphic importance, mainly in Cretaceous non-marine sections. The marine species, on the other hand, supply good paleoceanographyc data in marginal basins, including Pelotas Basin. In this work new Early Miocene species of the family Cytherellidae and the of genus Actinocythereis are proposed. Based on this taxonomic study some paleozoogeographic remarks are made, linking to the inception of the Antarctic Circumpolar Current and the Malvinas Current, to the dispersal of the ostracodes recorded in the Pelotas Basin. From the analysis of the core section 1300 m-1318 m of the offshore well 2-RSS-1 drilled by Petrobras in the 1970 decade, five species of cytherellids are recorded, two of them herein described, as follows: Inversacytherella atlantica sp. nov., Cytherella pelotensis sp. nov., Cytherella sp. 1, Cytherella sp. 2 and Grammcythella? sp. It is also proposed Actinocythereis imbeensis sp. nov., which constitutes the second species described for the genus in Brazil. Moreover, Krithe coimbrai, Krithe gnoma and Henryhowella kempfi, assigned in previous studies to the inception of cool water masses in Southern Brazilian coast, are recorded. The presence of Inversacytherella and Grammcythella, supply additional evidence for the faunal interchange between America and Oceania influenced by hydrological events in Southern Ocean along the Neogene. The Appendix 1 features the list and photographic documentation of other species registered.
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Wood, Roland Neville. "Ecology of Lake District Ostracoda." Thesis, University of Greenwich, 1992. http://gala.gre.ac.uk/6348/.
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Freshwater ostracods are potentially useful for environmental monitoring and, since their calcified valves may be preserved in lake sediments, are also valuable in palaeolimnological studies of environmental pollution such as eutrophication and surface water acidification. To establish a data-base of ostracod ecology, biannual survey work in 1989-1990 was performed in 75 lakes and tarns of a wide range of physico-chemical characteristics in the Lake District in Cumbria, ranging from large eutrophic lakes such as Windermere and Ullswater to tiny, upland acidic tarns. pH ranged from 4.3 (Black Pool) to 8.0 (Browns Tarn). Littoral margin samples were taken from all 75 sites and yielded 31 ostracod species, of which 8 were new to the Lake District fauna. The collection of multiple littoral samples from two sites demonstrated that a single sample produced an adequate faunal representation if it encompassed a variety of microhabitats. Statistical analysis, incorporating a multistage, multivariate technique, has shown that 18 species make up over 99% of the data set, and that 5 species, Cvpria ophthalmica, Cvclocypris ovum. Metacvpris cordata. Candona Candida and Cvpridopsis vidua. dominate the community in 71% of the sites containing ostracods, forming eight distinct assemblage groups. No ostracods were found in 13 of the 75 sites, 11 of which were acidic, having a pH of below 5.7. Equations were derived to predict both species distribution and diversity. Important predictors of community structures were shown to be pH, [Ca] 2+ , [Mg] 2+ , substrate, lake size and altitude. The equations were tested by further sampling of additional sites in the Lake District. Predictions of total species number and density generally provided an excellent fit to the observed data, although individual species predictions were poorer, especially in alkaline conditions. Substrate was not included in the analysis, due to quantitative difficulties, but this factor must be included in future predictive models as it was shown to be an important parameter in determining distribution. Deep-water sampling was carried out in 6 lakes. 10 species were collected, including Candona necrlecta, which was absent in the littoral samples. 9 species contributed to over 99% of the data set, and 2, Cypria ophthalmica and Candona Candida dominated the community in 75% of the sites containing ostracods. Community structure was predominantly determined by water depth (together with the associated temperature effect) and substrate. The sex ratio of Cyclocvpris ovum was shown be biased towards the female only at high alkalinities. Other species had sex ratios biased towards the male or female, the values independent of water quality. Large, swimming ostracod species were absent in sites containing fish. A series of laboratory experiments using three species of Ostracoda, (Cvpria ophthalmica. Cvpricercus fuscatus. and Eucvpris virens), and a predator (Gasterosteus aculeatus) correlated increasing ostracod size with an increased rate of predation, suggesting that predation could limit ostracod distribution. From the results of principal component analysis, it was concluded that the main characteristics that chemically differentiate the sites are calcium, magnesium, hydrogen and sodium ion concentrations. Toxicity tests were used to expose selected species to a wide range of calcium, magnesium, sodium and aluminium concentrations, at both neutral and acidic pH levels. Aluminium was selected as it has been highlighted as a major factor in the toxicity of acid waters. All species tolerated a wider spectrum of ionic concentrations than those in which they were recorded in the field, although the order of species survival in the experiments was similar to that found in the Lake District. It is suggested that whilst adult Ostracoda do not suffer from the acute toxicity of pH or aluminium, they may be unable to successfully reproduce in harsh environmental conditions. The waters of the English Lake District are not particularly species-rich due primarily to low alkalinity and low levels of dissolved cations, but also because they are cold. Only in small, ion-enriched pools is ostracod density sufficiently high to warrant their consideration as important detritivorous contributors in the cycling of nutrients. The Lake District fauna is compared with those recorded in other parts of Britain and Europe.
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Caputo, Clementina. "Ermeneutica e semiotica in archeologia : per una nuova interpretazione culturale della ceramica vascolare nell’Egitto greco-romano." Thesis, Poitiers, 2014. http://www.theses.fr/2014POIT5028/document.
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Cette recherche de doctorat concerne l’étude des fragments céramiques utilisés comme supports pour l’écriture dans l'Égypte gréco-romaine, c'est-à-dire les ostraca. Les deux groupes d'ostraca, objet de cette analyse, proviennent des fouilles archéologiques modernes effectuées dans deux sites qui se trouvent dans le désert occidental égyptien : Dime es-Seba/Soknopaiou Nesos (Fayoum) et Amheida/Trimithis (Dakhla). Le deux sites sont respectivement fouillés par la Mission archéologique du Centro di Studi Papirologici dell'Universita del Salento-Lecce (2003-2012) et de l’Université de New York -ISAW (2004-2013). Les aspects liés à la matérialité des ostraca (des fragments de récipients en céramique utilisés généralement pour écrire des textes en grec et démotique) ont été complètement ignorés par le passé en faveur de l’étude du texte. La raison principale de cette négligence est liée à la qualité médiocre du matériel céramique, considéré sans valeur. Par ailleurs, les études de céramologie en Égypte ainsi que l’étude des circuits économiques dans lesquels la poterie était utilisée sont très récents. En outre, il est communément admis que les scribes ramassait les fragments de céramique au hasard dans des dépotoirs et que n’y avait pas de sélection dans le choix des supports. Notre recherche démontre que ce concept est une fausse supposition, au moins pour ce qui concerne les deux groupes d'ostraca examinés. En revanche, il est clair que les scribes faisaient un choix sélectif des tessons selon leurs besoins et que, dans certains cas, il y avait une fragmentation ultérieure des morceaux. Rien a été laissé au hasard: le contenu des textes était strictement adapté à la nature de tessons utilisés comme support. De plus, la classification de la céramique des deux sites a été un point essentiel pour mettre en rapport la culture matérielle et l’organisation de la société égyptienne qui l’a produite entre le IIIe siècle av. J.-C. et le IVe siècle apr. J.-CThis doctoral dissertation focuses on the study of the pottery sherds that were used as writing surfaces for painted texts in Greco-Roman Egypt, called ostraka. Two groups of ostraka found in two modern excavations, Dime es-Seba/Soknopaiou Nesos (Fayyum), and Amheida/Trimithis (Dakhla Oasis) are the main subjects of the investigation. The two archaeological sites are under excavation by, respectively, the Centro di Studi Papirologici dell’Università del Salento-Lecce (2003-2012), and New York University-ISAW (2004-2013).Both settlements are located in the Western Desert of Egypt, in areas far from the Nile Valley and the main centers of power. The ostraka, which are re-used broken fragments of ceramic vessels with texts in Greek and Demotic, have been in the past seldom considered as archaeological objects because of the predominant importance of their texts. The material part of the ostraka being made from pottery vessels generally unrefined and of poor quality, have deterred most scholars from studying them accurately. Moreover, ceramological studies in Egypt and the interest towards the economy of the pottery manufacture and re-use are very recent. Finally, it is commonly believed that scribes collected the ceramic fragments to be used as ostraka randomly from open-air dumps. This research proved that this concept has to be considered as a wrong assumption, at least for the two groups of ostraka examined. On the contrary, it is very clear that the ancient scribes made a proper selection of the sherds they needed for specific purposes and that in some cases they reworked the sherds. It seems clear that nothing was left to the chance: the content of the texts and their use is strictly related to the kind of potsherds used to hold it. Additionally, the study of the ceramic types used in both settlements, analyzed as signifiers of the cultural environments for which they were produced, has shed light to the complex society of Egypt between the third century BCE and the fourth century CE
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Reeves, Jessica Marie. "The use of ostracoda in the palaeoenvironmental reconstruction of the Gulf of Carpentaria, Australia, from the last interglacial to present." Access electronically, 2004. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20050111.153534/index.html.
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Wood, Adrian Mark. "Recent Ostracoda and Mid-Pilocene global warming." Thesis, Aberystwyth University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496746.
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Ceolin, Daiane. "Ostracodes do cretáceo-paleógeno inferior da Bacia de Pelotas." Universidade do Vale do Rio dos Sinos, 2010. http://www.repositorio.jesuita.org.br/handle/UNISINOS/3084.
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CNPQ – Conselho Nacional de Desenvolvimento Científico e Tecnológico
O presente trabalho consiste no estudo taxonômico dos ostracodes marinhos da bacia de Pelotas e os respectivos aspectos paleoecológicos da assembléia no intervalo Cretáceo e Cretáceo – Paleógeno Inferior. Foram analisadas 479 amostras de calha, provenientes dos cinco poços 1-RSS-2, 1-RSS-3, 2-RSS-1, 1-SCS-3B e 1-SCS-2. A fauna registrada totalizou 98 espécimes, distribuídos em nove famílias, 21 gêneros, 34 espécies. Dois gêneros e duas espécies foram mantidos como táxons indeterminados. As espécies identificadas foram: Cytherella cf. C. araucana Bertels, 1974; Cytherelloidea spirocostata Bertels, 1973; Bairdoppilata triangulata Edwards, 1944; Actinocythereis indígena Bertels, 1969; Brachycythere gr. sapucariensis Krömmelbein, 1964; Wichmannella araucana Bertels, 1969 e Wichmannella meridionalis Bertels, 1969. Os gêneros mais diversificados foram Cytherella e Paracypris com sete e quatro espécies, respectivamente. O intervalo Turoniano foi o mais abundante, com a significativa presença dos gêneros Brachycythere e Cytherella . A família mais abundante foi a Trachyleberididae, com oito gêneros e 12 espécies, seguida da família Cytherellidae com dois gêneros e oito espécies. A passagem do limite Cretáceo – Paleógeno Inferior (K– Pg) na bacia de Pelotas foi marcada por uma mudança faunística com o desaparecimento dos gêneros, therelloidea, Argilloecia, Cythereis, Brachycythere, Pondoina e Rostrocytheridea, e o aparecimento de Neonesidea, Bairdoppilata, Ambocythere, Buntonia, Langiella?, Trachyleberis e Krithe . A associação dos ostracodes cretácicos na bacia de Pelotas sugere um ambiente marinho nerítico com águas quentes.
The taxonomic study of marine ostracods from Pelotas Basin and the respectives paleoecological assemblages aspects in the Cretaceous and Cretaceous – Lower Paleogene interval were studied. 479 cutting samples from wells 1-RSS-2, 1-RSS-3, 2-RSS-1, 1-SCS-3B e 1-SCS-2 were analized. 98 specimes belonging to 9 families, 21 genera and 34 species. 2 genera and 2 species were supported as undetermined taxon. The species identified were: Cytherella cf. C. araucana Bertels, 1974; Cytherelloidea spirocostata Bertels, 1973; Bairdoppilata triangulata Edwards, 1944; Actinocythereis indígena Bertels, 1969; Brachycythere gr. sapucariensis Krömmelbein, 1964; ichmannella araucana Bertels, 1969 and Wichmannella meridionalis Bertels, 1969. The most diversified genera were Cytherella and Paracypris with 7 and 4 species, respectively. The Turonian was the most ostracodes-rich interval with significant presence of the genera Brachycythere and Cytherella. The most abundant families were Trachyleberididae and Cyther ellidae with 2 genera and 8 species. The K – Pg boundary in the Pelotas basin is marked by a faunal change which disappearance the genera Cytherelloidea, Argilloecia, Cythereis, Brachycythere, Pondoina and Rostrocytheridea, and the first occurrence of Neonesidea, Bairdoppilata, Ambocythere Buntonia, Langiella?, Trachyleberis and Krithe. The Cretaceous ostracods association in Pelotas Basin sugest a neritic marin e environment with warm water temperatures.
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Toth, Emoke. "Changements paléoenvironnementaux dans la Parathéthys Centrale pendant le Samartien (Miocène moyen) : étude paléontologique de microfaunes et analyses géochimiques." Phd thesis, Université Claude Bernard - Lyon I, 2009. http://tel.archives-ouvertes.fr/tel-00843092.
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Les changements paléoenvironnementaux se produisant pendant le Sarmatien dans la Paratéthys Centrale ont été reconstitués par l'étude des foraminifères (36 espèces) et des ostracodes (28 espèces) de deux forages, combinée à une analyse géochimique de leurs squelettes calcitiques, des coquilles aragonitiques de gastéropodes et des dents phosphatiques de rongeurs.La composition de la microfaune indique que la connexion entre la Paratéthys et la Méditerranée est interrompue ou réduite à la base du Sarmatien mais qu'un bras de mer persiste entre Paratéthys Centrale et Paratéthys Orientale jusqu'à la fin du Sarmatien. Le Sarmatien inférieur est caractérisé par des eaux saumâtres peu profondes (maximum 80 m), bien ventilées, des températures stables (~ 15°C), un riche couvert végétal (algues et/ou phanérogames) et des efflorescences phytoplanctoniques périodiques. Un événement transgressif y est observé (TST de 3ème ordre; TB 2.6 du cycle global). Les changements faunistiques qui se produisent à la limite entre Sarmatien inférieur et moyen sont expliqués par un évènement de type HST accompagné de conditions dysoxiques. A la fin du Sarmatien moyen, une baisse du niveau marin relatif d'environ 50 m se produit et des eaux tempérées chaudes, plus saumâtres (17-23‰) et bien ventilées se mettent en place. Après un court épisode régressif, une connexion est rétablie entre la Paratéthys et la Méditerranée au début du Sarmatien supérieur. Des eaux chaudes (15-21° C), bien ventilées, correspondant à des lagunes marines et des marécages avec de fortes variations de la salinité (15-43 ‰) s'installent alors avant un isolement ultime de la Paratéthys qui se produit à la fin du Sarmatien.
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Larwood, Jonathan G. "Tertiary to recent evolution of Ostracoda on seamounts." Thesis, Cardiff Metropolitan University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400645.
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Frewin, J. "Palaeogene ostracods from the South African continental shelf." Master's thesis, University of Cape Town, 1987. http://hdl.handle.net/11427/17003.
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Bibliography: pages 147-155.92 cytheracean species, representing 44 genera are recorded from the Palaeogene Agulhas Bank and west coast margin of South Africa. 11 genera and 3 species are common with the Upper Cretaceous faunas. 12 genera (18 species) are left in open nomenclature. The following genera are represented:- Bythoceratina, Incongruellina, Ruggieria, Eucythere, Krithe, Parakrithe, Eucytherura, Cytheropteron, Ambostracon, Urocythereis, Muellerina, Leguminocythereis, Loxoconcha, Schlerochilus, Poseidonamicus, Bradleya, Agrenocythere, Australileberis, Chrysocythere, Costa, Echinocythereis, Haughtonileberis, Henryhowella, Parvacythereis, Phacorhabdotus, Soudanella, Stigmatocythere, Togoina, Trachyleberis, Veenia, Atlanticythere, Xestoleberis. Data on South African Cretaceous and Palaeogene ostracod faunas are discussed in terms of: faunal associations for the South African Palaeogene JC-1, Agulhas Bank and west coast provinces; characteristic species of Upper Eocene and Upper Eocene to Oligocene strata; generic variations across the Cretaceous/Tertiary boundary. Palaeo-environmental trends from a Cytheracea, Cypridacea + Bairdiacea, Cytherellidae (CCBC) plot indicate a sea level change from <100m (Palaeocene- Eocene), to shallower water with restricted circulation (Upper Eocene) to moderate depth, 100 - 200m (Lower Oligocene). South African faunas are compared with those from adjacent Palaeogene ostracod faunal provinces. Strong generic links occur with West Africa (8 genera in common) and Pakistan (9 genera in common) with only 3 genera in common with Australia and 3 with Argentina.
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Pollicott, Paul D. "The Silurian Ostracoda of the Oslo region, Norway." Thesis, University of Leicester, 1987. http://hdl.handle.net/2381/34940.
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A study of the ostracode fauna from the Silurian of Norway has been undertaken. All of the taxa recoverd and described are from the Llandovery and Wenlock Series; one species from the topmost part of the Ordovician of the Oslo region is also figured. Research has concentrated particularly upon the Palaeocopa Henningsmoen, 1954, but also includes the Leperditicopida Scott, 1961. The 'non-palaeocopes', because of particular problems related to preservation and taxonomy, are not treated as extensively. Primary revision has been made wherever possible. Such work has been augmented by studies of extensive new collections made from throughout the Oslo region, particularly from the Ringerike, Oslo-Asker and Holmestrand districts. This study has concentrated firstly on the taxonomy of the fauna. There are chapters on the Leperditicopa, Palaeocopa and 'non-palaeocopes'. Other chapters deal with the palaeoecology, biostratigraphy and correlation and affinities of the fauna. A full faunal and associated locality list, together with information on regional stratigraphy, is also presented. The fauna is 26 genera (2 new), 43 named species (14 new) and 15 other forms are described under open nomenclature. The Silurian ostracode fauna of Norway is mostly endemic (at specific level) but does have affinities with Gotland, Siberia and Britain. Ostracode potential for correlation between various districts of the Oslo region is best realised in the Steinsfjorden Formation. Standard micropalaeontological techniques have been used throughout, with most material being prepared by 'Vibrotool', and photographed on the Scanning Electron Microscope.
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Gammudi, Amar Mohamed. "Lower Palaeogene ostracoda from the Sirt Basin of Libya." Thesis, University of Glasgow, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299742.
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Medeiros, Caio Gurgel de. "Ostracodes da Formação Solimões, Brasil : contribuição à bioestratigrafia do Neógeno da Amazônia." reponame:Repositório Institucional da UnB, 2017. http://repositorio.unb.br/handle/10482/23710.
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Dissertação (mestrado)—Universidade de Brasília, Instituto de Geociências, Programa de Pós-Graduação em Geologia, 2017.Submitted by Raquel Almeida (raquel.df13@gmail.com) on 2017-06-20T20:32:49Z No. of bitstreams: 1 2017_CaioGurgeldeMedeiros.pdf: 3878046 bytes, checksum: b71e584315979e5bdda2c93c79ee65eb (MD5)
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A Formação Solimões compreende uma sucessão siliciclástica intercalada por níveis linhíticos, carbonáticos e ferruginosos, distribuindo-se espacialmente pelo noroeste do Brasil, sudeste da Colômbia e nordeste do Peru. O intervalo sedimentar estudado restringe-se ao Mioceno, sendo atribuído a uma sedimentação fluvial à fluvio-lacustre. A análise do material recuperado da sondagem 1-AS-33-AM, proveniente do Município de Atalaia do Norte, Estado do Amazonas, permitiu a identificação de 12 espécies de ostracodes e um nível de ocorrência de foraminíferos: Cyprideis aff. amazonica, Cyprideis caraionae, Cyprideis aff. graciosa, Cyprideis inversa, Cyprideis machadoi, Cyprideis multiradiata, Cyprideis pebasae, Cyprideis simplex, Cyprideis sulcosigmoidalis, Alicenula olivencae, Rhadinocytherura amazonensis e Perissocytheridea sp. A. Apesar do endemismo das espécies analisadas, foi possível a proposição de um zoneamento bioestratigráfico local em que os 404,15 metros da sondagem foram compartimentados em três biozonas e uma subzona: Biozona Cyprideis caraionae, Biozona Cyprideis multiradiata e Biozona Cyprideis sulcosigmoidalis, além da Subzona Rhadinocytherura amazonensis, inserida na Biozona Cyprideis multiradiata, de posição intermediária. O nível de ocorrência de foraminíferos assinala um evento ecológico local em que se observa o desaparecimento de seis espécies de ostracodes e uma visível alteração no sistema deposicional. Além da análise bioestratigráfica, dados geofísicos e petrográficos foram utilizados na compreensão deste episódio paleoambiental, interpretado como uma mudança ambiental provocada por uma incursão marinha no sistema fluvio-lacustre que dominou a atual região da bacia hidrográfica do rio Amazonas durante Mioceno. A correlação cronoestratigráfica foi realizada com base nas propostas de zoneamento efetuadas com base no material coletado na região fronteiriça entre Brasil, Colômbia e Peru.
The Solimões Formation comprises a siliciclastic succession with intercalated lignite, carbonate and ferruginous levels, spatially distributed throughout the northwest region of Brazil, southeast of Colombia and northeast of Peru. The studied sedimentary interval is restricted to the Miocene, being attributed to fluvial to fluvio-lacustrine sedimentation. The analysis of the material recovered from the 1-AS-33-AM core-drilling, from the Municipality of Atalaia do Norte, State of Amazonas, allowed the identification of 12 species of ostracode and one level of occurrence of foraminifera: Cyprideis aff. amazonica, Cyprideis caraionae, Cyprideis aff. graciosa, Cyprideis inversa, Cyprideis machadoi, Cyprideis multiradiata, Cyprideis pebasae, Cyprideis simplex, Cyprideis sulcosigmoidalis, Alicenula olivencae, Rhadinocytherura amazonensis and Perissocytheridea sp. A. The endemism of the analyzed species allowed the proposal of a local biostratigraphic zonation, in which the 404.15 meters of the core-drilling were compartmentalized in three biozones and one subzone: Cyprideis caraionae biozone, Cyprideis multiradiata biozone and Cyprideis sulcosigmoidalis biozone, in addition to the Rhadinocytherura amazonensis subzone, inserted in the Cyprideis multiradiata biozone, the intermediated one. The level of occurrence of foraminifera indicates a local ecological event in which the disappearance of six species of ostracods and a visible change in the depositional system are observed. In addition to the stratigraphic analysis, geophysical and petrographic data were used to recognize this palaeoenvironmental episode, interpreted as an environmental shift caused by a marine incursion into the fluvio-lacustrine system that dominated the region of the Amazon river basin during Miocene. The chronostratigraphic correlation was performed based on the zoning proposals made based on the material collected in the border region between Brazil, Colombia and Peru.
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Ben, Rouina Soumaya. "Reconstitution des paléoenvironnements et des évènements extrêmes au cours du Quaternaire à l'oued El Akarit (Golfe de Gabès, Sud de la Tunisie)." Thesis, Perpignan, 2016. http://www.theses.fr/2016PERP0036/document.
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Trois carottes de 5 à 6 m de profondeur ont été prélevées tout au long de l’oued El Akarit (Golfe de Gabès, Sud tunisien) : deux sur la rive Nord et une à l’embouchure. L’étude sédimentologique (granulométrie), minéralogique (minéraux argileux) et micropaléontologique (ostracodes, foraminifères et charophytes) et leur étude quantitative et qualitative ainsi que le calcul des indices de diversités de Shannon et d’équitabilité nous a permis de reconstituer l’évolution des paléo-environnements succédés depuis le Pléistocène dans la région El Akarit. La carotte à l’embouchure de l’oued El Akarit (carotte AK1), nous a permis de dater avec précision les dépôts étudiés et de reconstituer la chronologie des évènements ayant contrôlé la sédimentation. La phase pléistocène (>45000 ans B.P), milieu continental estuarien évoluant vers unevaste lagune très ouverte à la mer lors de la transgression marine pléistocène (MIS5e), par la suite l’installation d’un cordon sableux isole cette lagune de l’environnement marin. Les dépôts holocènes inférieurs et moyens sont absents dans l’embouchure de l’oued El Akarit à cause d’une émersion et non dépôt et/ou d’une érosion des dépôts. La phase Holocène supérieur (derniers 3000 ans B.P), se caractérise par la succession de trois épisodes d’évènements extrêmes (crues et tempêtes). A 1 et 2 km du rivage actuel (carotte AK2 et AK3 respectivement), les dépôts généralementcontinentaux montrent des intercalations des dépôts marins et des niveaux à galets enregistrant des évènements extrêmes. Les dépôts de ̴ 8000ans B.P de la poche à « Cardium » à 9 m d’altitude de la mer actuelle, montrent une influence marine (abondance des foraminifères planctoniques), il s’agit évidemment d’un évènement extrême exceptionnel qui provoquerait le transport des foraminifères planctoniques à l’intérieur de la lagune El AkaritThree cores varying from 5 to 6 m of depth were taken throughout in the El Akarit River (Gulf of Gabes, south of Tunisia): two on the left river bank and the last at the mouth. The study of the sedimentology (particle size), mineral (clay minerals) and micropaleontology (quantitative and qualitative study of ostracods, foraminifera, charophytes and the calculation of the Shannon / equitability diversity index) deposits content allowed us to reconstruct the paleoenvironments evolution since the Pleistocene in this region. The mouth core (AK1), permitted us to date precisely the studied deposits and reconstruct the events chronology controlling the sedimentation. The Pleistocene phase (> 45 000 years BP) shows a continental estuarine environment evolving toward a vast open lagoon during the Pleistocene marine transgression (MIS5e). Then, the formation of a sand bar isolates the lagoon from the marine environment. The lower and middle Holocene deposits are absent in the mouth deposits. This could be interpreted by the emersion of the zone or by the erosion of deposits. The late Holocene (last 3000 years B.P) phase is characterized by the succession of three extreme events (floods and storms) episodes. At 1 and 2 km from the current shoreline (AK2 and AK3 cores respectively), the continental deposits show an intercalation of marine deposits and pebble levels suggestive of an extreme events occurrence. The existence of the 8000 yr BP deposits "Cardium pocket” at 9 m of the current sea, show a marine influence (planktonic foraminifera abundance). It is apparently an exceptional event that would cause extreme transport of planktonic foraminifera inside the El Akarit lagoon
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Viehberg, Finn Andreas. "Quantitative paleoenvironmental studies using freshwater ostracods in northeast Germany." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=984425667.
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Syme, Anna. "A systematic revision of the cylindroleberididae (Crustacea Ostracoda Mydodocopa) /." Connect to thesis, 2007. http://eprints.unimelb.edu.au/archive/00002921.
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Galoukas, Stylianos Filippos. "Late Cenozoic ostracoda of Cyprus and their palaeoenvironmental interpretation." Thesis, University College London (University of London), 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283679.
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Slipper, Ian Jeffrey. "Turonian (Late Cretaceous) Ostracoda from Dover, south-east England." Thesis, University of Greenwich, 1997. http://gala.gre.ac.uk/6302/.
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Ostracod assemblages from samples collected through the Turonian Stage of the Late Cretaceous from Dover, Kent, south-east England, consist of one hundred and three species group taxa. These are described and illustrated. This represents a significant increase in the knowledge of the Turonian fauna, since previous estimates of the number of species present during the Turonian are less than thirty. This improvement has been brought about by the selection of an appropriate processing method. Freeze-thaw processing is recommended for chalks and hardgrounds which comprise much of the Turonian Stage. The white spirit, solvent method is shown to be preferable for marls. Nineteen species and six subspecies are here described as new: Polycope lunaplena sp. nov, Cytherella truncatoides sp. nov., Cytherella vulna sp. nov., Cytherella weaveri sp. nov., Cytherelloidea granulosa parca ssp. nov., Cardobairdia longitecta sp. nov., Bairdoppilata turonica sp. nov., Pontocyprella robusta cometa ssp. nov., Pterygocythereis (Diogmopteron) carolinae sp. nov., Bythoceratina (Bythoceratina) saxa sp. nov., Bythoceratina (Bythoceratina) staringi conmacula ssp. nov., Monoceratina minangulata sp. nov., Patellacythere weaveris sp. nov., Schulerides langdonensis sp. nov., Karsteneis nodifera tabasca ssp. nov., Karsteneis oculocosta sp. nov., Karsteneis petasus petasus sp. et ssp. nov., Karsteneis petasus antecursor sp. et ssp. nov., Karsteneis praekarsteni sp. nov., Idiocythere carburnensis sp. nov., Isocythereis postelongata sp. nov., Mauritsina? paradordoniensis sp. nov., Rehacythereis stellatus sp. nov., Rehacythereis venticursus venticursus sp. et ssp. nov., Rehacythereis venticursus patbrowni sp. et ssp. nov., and one new name, Bythoceratina (Bythocertatina) antetumida nom. nov. is introduced for a secondary junior homonym. By comparison with faunas from Devon and the Czech Republic, the biostratigraphical analysis is shown to only have only local significance due to diachronism of Ostracoda. This diachronism is used to explore migration pathways which suggest that the origin of the Turonian ostracod fauna may have had more than one source. A model relating ostracod diversity inversely to sea-level is given for the Cenomanian to Santonian stages of the Late Cretaceous which suggests that the sea-level at Dover during the Turonian was greater than previously thought, given its marginal setting.
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Gause, Austin. "Paleoenvironmental Reconstruction of Quaternary Saltville, Virginia, using Ostracode Autecology." Digital Commons @ East Tennessee State University, 2020. https://dc.etsu.edu/etd/3783.
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The Saltville valley in southwestern Virginia is home to Quaternary localities containing paleontological and archaeological remains. Historically the valley has been mined for salt and the small lakes, ponds and springs along the valley floor have a brackish signature. A preliminary report on the site’s ostracode fauna suggested that the site’s water was not always saline. This study analyzed modern and Quaternary ostracodes to understand the valley’s hydrologic and chemical evolution. Sediments contained primarily freshwater species, including the environmentally sensitive Candona crogmaniana. The presence of Pelocypris tuberculatum and a new Fabaeformiscandona species throughout a vertical section spanning the latest Pleistocene and Holocene suggests that ephemeral pools were being fed by freshwater springs throughout the latest Quaternary. Climate ranges, estimated through species autecology and MOTR, reveal that the site’s mean annual temperature was between 0 - 19.1℃. Ostracode salinity tolerances suggest that the site was fresh during the sampled record.
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Michelson, Andrew V. "Ecological, Taphonomic, and Paleoecological Dynamics of an Ostracode Metacommunity." University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1341597923.
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Orr, Robert James. "Upper Ordovician Ostracodes from Portrane, eastern Ireland." Thesis, Queen's University Belfast, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317101.
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Williams, Mark. "Ostracoda (Arthropoda) of the middle Ordovician Simpson Group , Oklahoma, USA." Thesis, University of Leicester, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315262.
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Barili, Giovani Manica. "SisAC - Sistema de Auxílio à Classificação. Estudo de caso: Ostracode." Universidade do Vale do Rio dos Sinos, 2011. http://www.repositorio.jesuita.org.br/handle/UNISINOS/4565.
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CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
O constante aumento no volume de informações em diversas áreas do conhecimento, via produção de material bibliográfico, multimídia e web, fruto dos avanços de pesquisas e estudos científicos, tem gerado um problema que é o gerenciamento e integração da informação de diferentes fontes. Com isso, a busca desses conhecimentos acaba tornando-se complexa e custosa, visto o volume de informações em alguns domínios de conhecimento. No entanto, esse conhecimento é de grande importância aos especialistas para raciocinar e chegar a conclusões que são utilizadas em tomadas de decisão ou como meio de solucionar problemas do domínio. Com base nessas necessidades, essa dissertação propõe um sistema de auxílio à classificação que tem como meta, oferecer funcionalidades que permitam aos usuários especialistas realizar a manutenção de informações de um domínio na base de conhecimento e a disseminação dela entre os usuários do sistema, por meio de consultas e/ou sugestões acerca do conhecimento resultante. Onde os resultados apresentados pelo sistema, gerados por meio de um motor de inferência, são baseados em Sistemas Especialistas, que busca construir raciocínios a partir de informações que o usuário possui sobre as observações do cenário do domínio. Juntamente com o sistema de inferência é proposto a associação de imagens relacionadas ao conhecimento, como forma de ilustrar as informações e descrições, e algoritmos de Processamento de Imagens para a redução da subjetividade nos casos de dúvida em relação às características visuais do estudo de caso, visto a falta de definições discretas de algumas informações que descrevem o conhecimento. Como estudo de caso para demonstrar a aplicabilidade do sistema proposto, o trabalho foi focado no domínio da paleontologia, mais especificamente na classificação de espécies de Ostracodes, organismos que representam grande importância para a identificação de fontes petrolíferas. Como resultado do trabalho obteve-se um sistema robusto e genérico, permitindo o armazenando de um grande volume de informações, separado pela área do conhecimento e subdividido por domínios de trabalho. Avaliações realizadas com usuários demonstram a efetividade da ferramenta e apontaram para a evolução de funcionalidades.
The constant increase in the volume of information of several areas of knowledge, through the production of bibliographic, multimedia and web material, is a result of advancements of research and scientific studies, and has led to issues regarding the management and integration of it. Therefore, the search for this knowledge becomes complex and difficult, considering the amount of information in some domains. However, this knowledge shows great importance to experts, who can analyze this information and use it to reach conclusions that are used in decision making or as a way for solving specific problems. Based on these requirements, this dissertation proposes a system to aid classification task, aiming to provide functionalities that allow the expert to maintain domain information in a knowledge base. Also, it is possible to disseminate this information to the others users through searches and/or suggestions, presenting information about the resulting knowledge. The results presented by the system are generated by an inference engine based on Expert Systems, which seeks to produce reasoning from users information about the domain. Along with the inference system is proposed a combination of images related to the knowledge as a way of illustrating the information and descriptions. Also, Image Processing algorithms are employed to reduce subjectivity in cases of uncertainty, regarding the visual characteristics of the case of study, considering the lack of discrete definitions for some information that describe the knowledge. A system was proposed for integrating the Expert Systems and Image Processing techniques. As a way to demonstrate the system applicability, a pertinent problem of paleontology domain focused in classification of Ostracodes species, which have great importance to petroleum exploration, was developed. The system was validated with users and experts that highlight its contribution: able to concentrate and store a big volume of information of many domains, incorporating support decision by image processing, and to be precise to map the expert knowledge. The experts cited as a major contribution that the system represents an application destined to inexperienced users, like students and novice researchers, used in the learning/training process.
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Smith, Robin James. "Biology and ontogeny of Cretaceous and Recent Cyprididae Ostracoda (Crustacea)." Thesis, University of Leicester, 1998. http://hdl.handle.net/2381/30470.
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Study of the biology and ontogeny of Cretaceous and Recent ostracods shows that the family Cyprididae exhibits conservative evolution over the last 100 million years. The Cretaceous cypridid ostracod Pattersoncypris micropapillosa Bate, 1972, with preserved appendages, is described and details of the limbs of its adults and juveniles are compared with Recent Cyprididae. A detailed study of the ontogeny of the Recent Cyprididae ostracod Eucypris virens Jurine, 1820) reveals that, with the exception of the last podomere on the antennules, the chaetotaxy (distribution pattern of setae) shows continual development on all podomeres of the limbs. Cyprididae ostracods have a pediform limb in the posterior part of the body, presumably to help them to attach to substrates; this is reflected by the pediform nature of one limb in all ontogenetic stages. This study has also shown that the fifth limb is more probably of thoracic origin and, hence, ostracods have only one pair of maxillae. The upper lip and hypostomes of 23 species of Cypridoidea (Podocopina) ostracods were studied and significant variation noted in morphology between species, genera and subfamilies. Several features of the upper lip and hypostome are described for the first time. The morphology of the upper lip can be used to identify species, but it cannot be used to diagnose genera or subfamilies. Spherical objects recovered from acetic acid preparation residues of vertebrate fossils from the Lower Cretaceous Santana Formation of north-east Brazil are postulated to be the eggs of the ostracod Pattersoncypris micropapillosa Bate, 1972. These spheres are phosphatized, range in diameter from 85 to 110 m, and are comparable in many respects to the eggs of several Recent ostracod species.
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Sáňka, Robert. "Novostavba věznice s ostrahou v Brně." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-227105.
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The subject of the diploma thesis is to architectural study of new security prison in Brno. Prisons are devices filling the disqualification of persons who have committed anti-social acts of a society that considers freedom and freedom of movement for one of the highest social values. The site is located in Propojený obrázek nelze zo brazit. Příslušný soub or byl pravděpodobně přesunut, přejmenován nebo odstraněn . Ověřte, zda propojení odkazuje na sp ráv ný so ubor a umístění. the outskirts of Brno, Brno-Slatina. The main idea is to use clear communication connections between the buildings, which are structured according to the appropriate method of use; its structurally functional organization and clearly indicate its operating mode. Harmony of the whole is then expressed by a suitable composition of objects and surfaces areal vegetation, where the area according to the scheme uniformly distributed and completed at the close of the outdoor sports area.
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Cartier, Rosine. "Trajectoires des écosystèmes lacustres alpins depuis 13 500 ans dans les Alpes méditerranéennes (massif du Mercantour, France) : entre forçage climatique et pression anthropique plurimillénaire." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4342.
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Ce travail de thèse a permis de reconstituer la dynamique à long terme de deux écosystèmes lacustres alpins dans les Alpes du sud grâce à l’étude (1) de la variabilité tardi-holocène des paramètres physico-chimiques de l’eau, des niveaux lacustres et des dynamiques de communautés aquatiques, et (2) des types de réponse de ces environnements à des perturbations externes en lien avec les changements du bassin versant et du climat. Les deux séquences sédimentaires prélevées par carottage au lac d’Allos et au lac Petit (Massif du Mercantour, 2200 m) ont permis de reconstituer en détail l’évolution des écosystèmes lacustres depuis les derniers 13,500 cal. BP grâce à trois grands volets : (1) l’étude de fossiles d’espèces aquatiques indicatrices des conditions de vie dans le milieu lacustre (les diatomées et les ostracodes) ; (2) l’analyse des isotopes de l’oxygène contenus dans ces mêmes fossiles afin de reconstituer un signal paléohydrologique ; (3) une comparaison multi-proxy permettant de mettre en lien les changements de l’écosystème lacustre avec les dynamiques du bassin versant. Les résultats obtenus et leur confrontation à un cadre multidisciplinaire très documenté ont permis d’évaluer l’importance première des processus érosifs et des modifications du couvert végétal sur la dynamique lacustre, au travers de changements majeurs dans les communautés aquatiques et les niveaux trophiques. Enfin, les données isotopiques mesurées sur les fossiles de diatomées et d’ostracodes ont mis en évidence des variations paléohydrologiques inédites pour la région : cette approche, novatrice ouvre la perspective d’une reconstitution paléoclimatique de référence pour les Alpes du sudThe thesis is devoted to the reconstruction of long-term changes in two lacustrine ecosystems in the Southern Alps. This study aims at assessing (1) the lateglacial-holocene variability of water physico-chemistry, lake levels and aquatic species dynamics; and (2) the environmental responses of the lacustrine ecosystem to external forcing (watershed and climate changes), with the study of Lake Allos and the Lake Petit (Mercantour National Park, 2200 m a.s.l). The two sedimentary cored profiles provided a detailed record of the past lacustrine dynamics since 13.500 cal. BP. An integrative approach was carried out including (1) the study of fossils of aquatic bioindicators species (diatoms and ostracods) informing about changes in lacustrine living conditions ; (2) the analysis of oxygen isotopes recorded by these aquatic fossils tracing a palaeohydrological signal ; (3) a multiproxy comparison linking the aquatic environment with changes in watershed dynamics. These results integrated into a rich multidisciplinary framework evidenced the major role of erosion processes and changes in vegetation cover as factors triggering lake responses to disturbance, with concomitant changes in aquatic communities and trophic levels at several timescales. The different geological settings and lake morphologies have also played a significant role, modulating changes in benthic and planktonic aquatic communities over long time periods. Finally, oxygen isotopes records allow to trace for the first time palaeohydrological changes in the region: this innovative approach represents an original outcome for reconstructing a reference past climate for the Southern Alps
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Pereira, Elise Vargas. "Taxonomia e ocorrência das espécies do gênero bromelícola Elpidium (Crustacea: Ostracoda) em áreas de mata atlântica no estado de Santa Catarina, Brasil." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/41/41133/tde-22102013-154642/.
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Trabalhos recentes realizados no Brasil apresentaram pelo menos 5 espécies do gênero Elpidium, ostrácode de fitotelmata de bromélia, embora o trabalho de revisão desse gênero propusesse apenas a espécie tipo, E. bromeliarum, com registros do Rio Grande do Sul ao Espírito Santo. No presente trabalho, foram descobertas novas espécies de Elpidium, em amostras coletadas em 2009, em um transecto sul-norte no estado de Santa Catarina, incluindo regiões próximas à localidade tipo de E. bromeliarum. Os animais foram coletados com pipeta e conservados em álcool 70%; as valvas, fotografadas ao microscópio eletrônico de varredura e armazenadas em lâminas micropaleontológicas; os apêndices corporais, dissecados sob estereomicroscópio e transferidos para meio CMC-9AF. Ilustrações dos apêndices das espécies foram realizadas sob câmara clara, sendo que as características diferenciais para cada uma se localizaram no apêndice sexual masculino. Os 4.116 espécimes inventariados, foram contados por sexo, idade e espécie. Mensurações do comprimento, largura e altura das carapaças de 235 espécimes foram realizadas, resultando em 705 medidas. Foram encontradas três espécies de Elpidium: E. bromeliarum e mais duas espécies novas (E. fritzmulleri e E. coimbrai). Diferenças visualizadas nas abas terminais dos apêndices sexuais e tamanhos de carapaças para alguns espécimes de E. bromeliarum foram consideradas como variações intraespecíficas. Um indivíduo que na verdade pertence a E. fritzmulleri sp. n., encontrada em Araranguá, Laguna e Botuverá, havia sido registrado como E. bromeliarum, em Torres, Rio Grande do Sul, em um trabalho anterior. A segunda espécie nova foi encontrada em Içara e Imbituba. Foi elaborada uma chave dicotômica de identificação para as espécies formalmente descritas e nomeadas de Elpidium. As mensurações das carapaças das espécies novas revelaram diferentes tamanhos preferenciais entre as espécies, classificados como grande, médio e pequeno, variando entre 50 a 120 μm. As variáveis ambientais não interferiram de forma determinante na ocorrência das espécies encontradas.Recent studies conducted in Brazil have shown at least 5 species of Elpidium, ostracod from bromeliad phytotelmata, although the work of revision of this genus propose only the type species, E. bromeliarum, with records from Rio Grande do Sul to Espírito Santo. In the present work, were inventoried new species of Elpidium, obtained in samples collected in 2009, in a south-north transect in the state of Santa Catarina, including regions near the type locality of E. bromeliarum. The animals were collected with a pipette and preserved in 70% alcohol; valves were photographed under a scanning electron microscope and stored on micropaleontological slides; appendages were dissected on slides with glycerin under a stereomicroscope and transferred to CMC-9AF mounting medium. Illustrations of the appendages were performed under camera lucida, and the differential characteristics for each were located in the male sexual appendage. The 4.116 specimens inventoried were counted by sex, age and species. Measurements of length, width and height of the shell of 235 specimens were performed, resulting in 705 measures. Three species of Elpidium were recovered: E. bromeliarum and two new species (E. fritzmulleri e E. coimbrai). Differences seen in the end flap of the sexual appendages and sizes of shells of some specimens of E. bromeliarum were considered as intraspecific variation. An individual who actually belongs to E. fritzmulleri sp.n., found in Araranguá, Laguna and Botuverá, was recorded as E. bromeliarum in Torres, Rio Grande do Sul, in a previous work. The second new species was found in Içara and Imbituba. An dichotomous key for identification of species formally described and named of Elpidium was created. Measurements of shells of the new species revealed different preferred sizes between species, classified as large, medium and small, ranging from 50 to 120 μm. Environmental variables did not interfere significantly in the occurrence of species found.
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Pereira, Margarida Jorge Simões. "Ostracodos da sondagem de Belverde (Miocénico da Bacia do Baixo Tejo)." Master's thesis, Universidade de Évora, 2014. http://hdl.handle.net/10174/13043.
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Os ostracodos (Crustacea: Ostracoda) são organismos ecologicamente muito sensíveis que fossilizam com facilidade, preservando as estruturas da carapaça. O estudo das associações de ostracodos fósseis, em sucessões estratigráficas, permite inferir os paleoambientes (de água doce, salobra, litoral, infralitoral e circalitoral) e registar a evolução dos mesmos.
Esta tese retoma o estudo deste grupo, com a revisão e síntese dos principais resultados de sistemática, biostratigráficos e paleoecológicos, e tentando enquadrá-los no actual quadro cronostratigráfico para o Miocénico Inferior da bacia do Baixo Tejo (BBT). Efectuou-se o estudo preliminar dos ostracodos obtidos na Sondagem de Belverde (Península de Setúbal, 38º 35’ 34,1’’/9º 8’ 24,7’’) pertencentes ao Miocénico da parte distal da BBT.
Foram identificados os paleoambientes do Miocénico Inferior da BBT e correlacionados com os ciclos eustáticos. A análise das diferentes associações de ostracodos, correspondentes a diferentes profundidades, permitiram reconstituir paleoambientes de águas salobras, como estuários e lagoas, aquando das regressões ocorridas e, paleoambientes tipicamente marinhos consequentes das transgressões ocorridas; Ostracods from Belverde Borehole (Miocene of the Lower Tagus Basin)
Abstract:
Ostracods (Crustacea: Ostracoda) are organisms ecologically very sensible that fossilize easier, preserving the whole carapace characteristics. The study of the ostracod fossil assemblages, in the stratigraphic sequences, allows us to infer palaeoenvironments (freshwater, brackish, and marine) and record their evolution.
This dissertation resumes the study of this group, with the review and summary of the main results in systematic, biostratigraphy and paleoecology, and attempt to frame them in the recent chronostratigraphical scenario of the Lower Miocene of the Lower Tagus basin (LTB). It was done the preliminary study of the ostracods of the Belverde Borehole (Setúbal peninsula, 38º 35’ 34,1’’/9º 8’ 24,7’’) belonged to the Miocene distal part of the BBT.
It has been identified the palaeoenvironments of the Lower Miocene of BBT and correlate with the eustatic cycles. The analysis of the different associations, which correspond to different depths, enabled the reconstruction brackish water palaeoenvironments, like estuaries and lagoon, when the regressive episodes occurred, and typical marine environments consequent of transgressions.
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El-Waer, Ahmed Ammar. "The Upper Cretaceous and Lower Tertiary Ostracoda from northwestern offshore Libya." Thesis, University of Hull, 1990. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420751.
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Trubee, Kenton J. "Ostracode community response to anthropogenic modification of estuaries in southwestern Florida." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1366807735.
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Dickson, Carol Paula. "Quaternary ostracoda from the Celtic and Irish seas : a palaeoenvironmental study." Thesis, Aberystwyth University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.603582.
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Somasundaram, Ramanathan, and Ramanathan Somasundaram. "Ostracode Taphonomy from Modern Shell Beds in Lake Tanganyika, East Africa." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/626607.
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Lake Tanganyika (LT), in the East African Rift, contains extensive shell beds that are noteworthy because the gastropods composing most of the LT shell beds are absent from the living in-situ assemblages of organisms hosted by the shell bed substrate. Understanding the geologic and biologic processes that formed these beds has the potential to improve our understanding of fossil shell beds in East Africa. The shell beds may also record recent lake-wide environmental change from climate or watershed impacts, which may be evident through community and taphonomic changes in the populations of shelly invertebrates and so the research seeks to examine whether shell bed substrates have experienced significant anthropogenic impacts that have altered the living assemblages. We investigated total abundance and taphonomic properties of ostracode fossils from shell beds at two sites in LT, one near the Luiche River Delta (a highly deforested site along the northern Tanzanian coast) and another near the Mahale Mountains National Park, an area of substantially lower human population density, 157 km to the south of the Luiche site. In laymen terms, ostracods are microscopic crustaceans that thrive in lacustrine environments and serve as very good indicators for past paleo-environmental and paleochemical reconstructions (Cohen, Nielsen 1986). We studied ostracode assemblage because of its sensitivity to chemical and physical changes in the environment. Ostracods indicate changes in shell beds. The analysis was done by sampling each site along 8 depth transects at the Luiche site and 7 transects at the Mahale site at water depths of 3, 6, 9, 12, 15, 20, 30, 40, 50, and 60 meters. We analyzed total abundance, %valves vs. carapace, % adult vs. juvenile, % carbonate coated, reduction stained, oxidation stained, and %broken vs intact valves for ostracode shells. Results of LT show that there is a decrease in proportion of broken valves, slight decrease in carbonate staining, and an increase in reduction staining and proportion of whole carapaces with increasing water depth. Results of MT show that there is a decrease in broken valves and whole carapaces and an increase in adults, carbonate coated and reduction stained ostracodes with depth. The implications of this study towards paleo-limnology is that the pattern and post-mortem alterations record environmental conditions in shell bed area which can be used to further research in the study of ostracods and environmental changes.
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Salel, Tiphaine. "Dynamique des environnements fluvio-lagunaires du Narbonnais à l'Holocène (Golfe du Lion, France)." Thesis, Montpellier 3, 2018. http://www.theses.fr/2018MON30083.
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Le paysage littoral de la basse vallée de l’Aude est composé d’une mosaïque de milieux laguno-deltaïques mobiles à l’échelle des derniers millénaires. Du fait de cette mobilité et de l’ancienneté de l’occupation humaine, continue depuis le Néolithique, la compréhension des dynamiques environnementales passées constitue une problématique incontournable de la recherche archéologique narbonnaise. Le travail que nous présentons vise à identifier et expliquer les transformations de ce paysage fluvio-lagunaire à l’Holocène, à partir de l’analyse sédimentologique et micropaléontologique des enregistrements sédimentaires datés au radiocarbone. Dans un premier temps, une étude de la répartition spatiale actuelle des ostracodes des lagunes et embouchures fluviales modernes est proposée en vue d’utiliser cette microfaune comme bioindicateur privilégié des conditions environnementales passées dans la zone d’étude. Elle repose sur le prélèvement d’une soixantaine d’échantillons de sédiments de surface provenant de différents complexes paraliques de Méditerranée nord-occidentale. Les assemblages d’ostracodes actuels permettent de caractériser différents stades d’isolement des bassins, des lagunes complètement fermées jusqu’aux baies largement ouvertes sur la mer, ainsi que la variabilité intra-lagunaire des milieux en relation avec la proximité des embouchures et des graus. La base de données présentée peut être utilisée, à titre comparatif, pour reconstituer les dynamiques géomorphologiques littorales holocènes, telles que la mobilité deltaïque et l’évolution des systèmes barrières-lagunes, dans le golfe du Lion. Dans un second temps, l’étude des enregistrements sédimentaires a permis d’appréhender l’évolution du littoral narbonnais à l’Holocène. Elle repose sur neuf sondages carottés répartis sur les deux branches deltaïques, méridionale et orientale, de l’Aude. Les résultats obtenus permettent de proposer un scénario paléogéographique reconstituant la dynamique des environnements de la basse vallée depuis 9500 ans cal. BP, en même temps qu’ils renseignent le contexte local de la remontée du niveau marin holocène dans l’intervalle 9500-6000 ans cal. BP. Plusieurs problématiques sous-jacentes à l’évolution des paléoenvironnements littoraux narbonnais sont discutées. Elles concernent les modalités de la transgression holocène dans les lagunes du golfe du Lion, l’enregistrement d’un événement marin extrême en fond de ria vers 5200-5000 ans cal. BP, et le rythme de progradation accéléré du delta de l’Aude durant le dernier millénaire. L’identification de deux périodes d’enrichissement en plomb cohérentes avec les principaux pics d’exploitation minière connus en Languedoc à la charnière du changement d’ère et au début du Moyen-âge classique suggère un enregistrement de la fluctuation historique des activités métallurgiquesThe present day Aude valley’s coastal landscape is the result of unstable lagoonal and deltaic environments during the last millennia. The understanding of past environmental dynamics is a key issue of the local ar-chaeological research, because since the Neolithic period human beings have settled in this area. This work aims to identify and explain the fluvio-lagoonal landscape’s evolution in the Narbonne region during the Holocene by using sedimentology, micropalaeontology and radiocarbon sediment datations. First, we analysed the present ostracods spatial distribution in modern lagoons and river mouths in order to use this microfauna as a bioindicator of past environmental conditions in the study area. Various aquatic envi-ronments (60) from the NW Mediterranean coastline were studied. The present ostracod assemblages characterize different stages of isolation, from completely closed lagoons to widely open marine bays, as well as intra-lagoonal environmental variability in relation to the inlets and river mouth proximities. The proposed database can be used to reconstruct coastal geomorphologies and dynamics, such as the holocene evolution of delta and barrier-lagoon systems in the Gulf of Lion. Second, sedimentary recording studies have been used to analyse the Narbonne’s coastal evolution. This study is based on nine cores distributed over the southern and eastern deltaic branches of the Aude river. With theses results, it is possible to propose a palaeogeographic scenario associated with the environmental dynamics of the lower valley since 9500 years cal. BP. This same data informs us about the local context of the Holocene sea level rise during the 9500-6000 years cal. BP. Several issues are discussed such as : the Holocene’s transgressions of the Gulf of Lion’s lagoons, the extreme marine event near the bay head delta around 5200-5000 years cal. BP, and the Aude delta’s rapid progradation during the last millennium. Additionally, we identified two periods of lead enrichment; which are consistent with the major mining peaks known in Languedoc (beginning of the first century AD - beginning of the classical Middle ages) and suggest a record of fluctuating metallurgical activity
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Dojen, Claudia. "Early Devonian ostracods from Celtiberia (NE Spain) taxonomy, palaeoecology, biostratigraphy, and biogeography /." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=97774082X.
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Wells, Kathryn J. "Paleoecology of Beringian Lacustrine Deposits as Indicated by Northern Hemisphere Ostracode Biogeography." Kent State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=kent1318855400.
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Bridgwater, N. D. "Non-marine ostracods as indicators of Holocene environmental change in central Mexico." Thesis, Kingston University, 1995. http://eprints.kingston.ac.uk/20581/.
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A late Holocene palaeolimnological record for Central Mexico has been obtained from Lake Pátzcuaro, using recent and fossil ostracods. Lake Pátzcuaro (19[degrees]35' N-19[degrees]45t N,lOI °32' W-lOl [degrees]43' W) is a closed-basin lake which responds rapidly to changes in the ratio of precipitation/evaporation in the region. The waters of Lake Pátzcuaro are of Na-HC03 type and are currently close to the branchpoint for calcite precipitation. The records from four lake-sediment cores, dated by AMS radiocarbon methods, cover the last 3,650 years. Work on the sediment cores involved ostracod faunal palaeoecology coupled with analysis of the trace-element (Mg/Ca and Sr/Ca) and stable-isotope (180/160 and 13C/12C) composition of ostracod valves. The faunal distribution is determined by the presence or absence of aquatic vegetation and, to a lesser extent, salinity. The 180/160 and 13C/12C ratios in ostracod calcite show good agreement with palaeolimnological inferences from the faunal assemblages, primarily recording changing precipitation/evaporation and primary productivity levels, respectively. The trace-element chemistry of ostracod valves shows poor agreement with the faunal and isotope records and appears to be dependent on a number of complex factors, such as the changing solute composition of surface runoff, which is, in tum, dependent on the degree of weathering of the regolith through which the water has passed. This study shows that wetter conditions existed in Central Mexico between approximately 3,650-2,300, 1,300-800 and 500-300 yr BP, characterised by fluctuating lake levels. Catchment stability was associated with the onset of these wetter conditions, which ultimately increased primary productivity in the lake, owing to reduced turbidity. Each wet phase was separated by a prolonged dry period, during which time, the lake level was relatively stable. The good agreement between the findings of this study and those elsewhere within the Neotropics suggests that these abrupt climate changes occurred on at least a regional scale.
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De, Deckker P. "Australian Quaternary studies : a compilation of papers and documents submitted for the degree of Doctor of Science in the Faculty of Science, University of Adelaide /." Title page, contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09SD/09sdd299.pdf.
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