Dissertationen zum Thema „Oxfordium“
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Rais, Pauline Sophie Claudine. „Evidence for a major paleoceanographic reorganization during the Late Jurassic : insights from sedimentology and geochemistry /“. Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=16932.
Der volle Inhalt der QuelleReyle, Michael. „Fazies- und Beckenentwicklung im Oxfordium (Oberjura) des zentralen Lusitanischen Beckens (Portugal)“. [S.l. : s.n.], 2004. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11103981.
Der volle Inhalt der QuelleLaternser, Ralf. „Oberjurassische Korallenriffe von Nordostfrankreich (Lothringen) und Südwestdeutschland“. [S.l. : s.n.], 2001. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB9372874.
Der volle Inhalt der QuelleCäsar, Sebastian [Verfasser], und Christian [Akademischer Betreuer] Betzler. „Sedimentologie und Sequenzstratigraphie oberjurassischer Karbonate von Norddeutschland (Oxfordium, Kimmeridgium, Niedersächsisches Becken) / Sebastian Cäsar. Betreuer: Christian Betzler“. Hamburg : Staats- und Universitätsbibliothek Hamburg, 2012. http://d-nb.info/1025150937/34.
Der volle Inhalt der QuelleCäsar, Sebastian Verfasser], und Christian [Akademischer Betreuer] [Betzler. „Sedimentologie und Sequenzstratigraphie oberjurassischer Karbonate von Norddeutschland (Oxfordium, Kimmeridgium, Niedersächsisches Becken) / Sebastian Cäsar. Betreuer: Christian Betzler“. Hamburg : Staats- und Universitätsbibliothek Hamburg, 2012. http://nbn-resolving.de/urn:nbn:de:gbv:18-57862.
Der volle Inhalt der QuelleMahjoub, Mohamed. „Modélisation du couplage endommagement-perméabilité dans les géomatériaux anisotropes. Application aux ouvrages souterrains du site de Bure“. Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLEM043/document.
Der volle Inhalt der QuelleThis thesis aims to introduce a new hydromechanical constitutive model taking into account both initial and induced anisotropies and the impact of the mechanical damage on the permeability. To build this model, a new modeling approach is developed allowing the extension of mechanical behavior laws from isotropic materials to transversely isotropic materials. This approach is used, within the framework of continuous media with internal variables, to propose an elasto-viscoplastic behavior law that distinguishes between compressive and tensile loading regimes. A second order tensor is introduced to describe the induced anisotropy due to tensile loadings, and a scalar internal variable is employed to account for hardening and softeningof the material due to compressive loadings. Under complex loadings, these two mechanisms are coupled, and the effect of cracks closing/reopening is taken into consideration. The damage-permeability coupling is modeled by the introduction of a phenomenological law linking the material intrinsic permeability to the mechanical internal variables.The developed model is applied to the case of the underground drifts of Bure site in order to better understand the mechanisms of hydromechanical properties alteration, around drifts and storing cells. Not only the impact of the excavation operations is considered but also the consequences of the overpressures caused by the produced hydrogen due to the corrosion of the metallic parts of nuclear waste containers
Collin, Pierre-Yves. „Environnements, géochimie et processus de formation de séries condensées au Callovo-Oxfordien : du Bassin de Paris à des considérations globales“. Dijon, 2000. http://www.theses.fr/2000DIJOS092.
Der volle Inhalt der QuelleMélendez, Hevia Guillermo. „El Oxfordiense en el sector central de la Cordillera Ibérica, provincias de Zaragoza y Terúel /“. [Zaragoza] : [Terúel] : Institución Fernando el Católico ; Instituto de estudios turolenses, 1989. http://catalogue.bnf.fr/ark:/12148/cb35702465f.
Der volle Inhalt der QuelleMahjoub, Mohamed. „Modélisation du couplage endommagement-perméabilité dans les géomatériaux anisotropes. Application aux ouvrages souterrains du site de Bure“. Electronic Thesis or Diss., Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLEM043.
Der volle Inhalt der QuelleThis thesis aims to introduce a new hydromechanical constitutive model taking into account both initial and induced anisotropies and the impact of the mechanical damage on the permeability. To build this model, a new modeling approach is developed allowing the extension of mechanical behavior laws from isotropic materials to transversely isotropic materials. This approach is used, within the framework of continuous media with internal variables, to propose an elasto-viscoplastic behavior law that distinguishes between compressive and tensile loading regimes. A second order tensor is introduced to describe the induced anisotropy due to tensile loadings, and a scalar internal variable is employed to account for hardening and softeningof the material due to compressive loadings. Under complex loadings, these two mechanisms are coupled, and the effect of cracks closing/reopening is taken into consideration. The damage-permeability coupling is modeled by the introduction of a phenomenological law linking the material intrinsic permeability to the mechanical internal variables.The developed model is applied to the case of the underground drifts of Bure site in order to better understand the mechanisms of hydromechanical properties alteration, around drifts and storing cells. Not only the impact of the excavation operations is considered but also the consequences of the overpressures caused by the produced hydrogen due to the corrosion of the metallic parts of nuclear waste containers
Aburto, Mardones Danitza. „Filtrage géostatistique de données géophysiques en vue de la cartographie de l’impédance d’une formation argileuse : exemple du Callovo-Oxfordien de Meuse“. Thesis, Paris, ENMP, 2012. http://www.theses.fr/2012ENMP0012/document.
Der volle Inhalt der QuelleIn the framework of researches carried out by ANDRA (the French agency for nuclear waste), which aim at evaluating the feasibility of creating a repository of radioactive waste in the Callovo Oxfordian clay formation. This thesis studies two key steps to obtain a 3D image of the formation: its geometry and its internal heterogeneity. The geometry of the sedimentary formation is determined from seismic time picking along profiles. These profiles are oriented along two main directions. At the intersections, the values registered by two profiles are different. The low number of intersections does not allow a precise study of the spatial behavior of these differences; they are analyzed via the pseudo-cross-variogram. The variography analysis allows the choice of a coherent model for all the profiles, from which an estimation of the corrected time is presented. The internal heterogeneity is performed through the study of the impedance, a variable linked to the intrinsic properties of the rock. Two types of measurements are available. On one hand, the seismic impedance resulting from the geophysical inversion of the amplitude recorded along seismic reflection profiles is densely distributed in the area of interest. On the other hand, the impedance log, resulting from the product of rock density and P wave velocity, is known at only few wells. Bivariate spatial behavior along the vertical direction has allowed the formulation of the following hypothesis: each impedance measurement can be decomposed into a sum of a variable Z (common to both measures) and a residual specific to each measure. Under certain supplementary hypotheses, it is possible to estimate the common component along the seismic sections. Some complements to these studies are mentioned, for example the correspondence between geophysical and geostatistical methods or the consideration of uncertainty in the amplitudes
Guayacan, Carrillo Lina María. „Analysis of long-term closure in drifts excavated in Callovo-Oxfordian claystone : roles of anisotropy and hydromechanical couplings“. Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1120/document.
Der volle Inhalt der QuelleThe French National Radioactive Waste Management Agency (Andra) began in 2000 the construction of an Underground Research Laboratory (URL) with the main goal of demonstrating the feasibility of a geological repository in Callovo-Oxfordian claystone. Several research programs have taken place to improve the knowledge of the rock properties and its response to the excavation progress. A network of experimental drifts has been constructed with variations on: excavation method, structure geometry, supports system and orientations with respect to principal stresses’ directions. In each drift different sections have been instrumented to monitor the hydro-mechanical behavior of the rock mass formation. Continuous monitoring of the excavated zone around the drifts in the main level (-490 m) revealed the development of a fractured zone (extensional and shear fractures) induced by the excavation. The extent of this fractured zone depends on the drift orientation regarding the in-situ stress field. Accordingly, the convergence measurements showed an anisotropic closure which depends also on the drifts’ orientations. Moreover, marked overpressures and an anisotropic pore pressure field around the drifts have been also observed.The approach proposed in this work is mainly based on a direct analysis of the convergence measurements, for studying the anisotropic response of the rock formation during and after excavation. The convergence evolution is analyzed on the basis of the semi-empirical law proposed by Sulem et al. (1987) [Int J Rock Mech Min Sci Geomech Abstr 24: 145–154]. The monitoring and analysis of convergence data can provide a reliable approach of the interaction between rock mass and support. Therefore, the anisotropy and the variability of the closure are analyzed taking into account different field cases: drifts excavated in two different orientations (i.e. influence of the initial stress state), different methods, sizes and rates of excavation and different supports systems with different conditions of installation. This broad range of cases permits to refine the analysis for reliable predictions of the convergence evolution in the long term. This approach can thus be used for the design of various types of support and the evaluation of its performance in the long term.On the other hand, the pore pressure evolution induced by excavation of drifts as recorded in situ has been analyzed. The anisotropic response observed in-situ suggests that the intrinsic anisotropy of the material plays a key role in the response of the rock formation. To understand these phenomena, an anisotropic poroelastic analysis of the pore pressure evolution induced by the drift excavation is performed. The main goal is to simulate the main trends of the pore pressure evolution with a simple model taking into account the inherent anisotropy of the material. Finally, an analysis of the onset of failure shows the key role of the hydro-mechanical coupling on the extension of the failed zone around the drifts
Bonnot, A. „Les aspidoceratidae (ammonitina) en Europe occidentale au callovien supérieur et à l'oxfordien inférieur“. Dijon, 1995. http://www.theses.fr/1995DIJOS057.
Der volle Inhalt der QuelleAburto, Mardones Danitza. „Filtrage géostatistique de données géophysiques en vue de la cartographie de l’impédance d’une formation argileuse : exemple du Callovo-Oxfordien de Meuse“. Electronic Thesis or Diss., Paris, ENMP, 2012. http://www.theses.fr/2012ENMP0012.
Der volle Inhalt der QuelleIn the framework of researches carried out by ANDRA (the French agency for nuclear waste), which aim at evaluating the feasibility of creating a repository of radioactive waste in the Callovo Oxfordian clay formation. This thesis studies two key steps to obtain a 3D image of the formation: its geometry and its internal heterogeneity. The geometry of the sedimentary formation is determined from seismic time picking along profiles. These profiles are oriented along two main directions. At the intersections, the values registered by two profiles are different. The low number of intersections does not allow a precise study of the spatial behavior of these differences; they are analyzed via the pseudo-cross-variogram. The variography analysis allows the choice of a coherent model for all the profiles, from which an estimation of the corrected time is presented. The internal heterogeneity is performed through the study of the impedance, a variable linked to the intrinsic properties of the rock. Two types of measurements are available. On one hand, the seismic impedance resulting from the geophysical inversion of the amplitude recorded along seismic reflection profiles is densely distributed in the area of interest. On the other hand, the impedance log, resulting from the product of rock density and P wave velocity, is known at only few wells. Bivariate spatial behavior along the vertical direction has allowed the formulation of the following hypothesis: each impedance measurement can be decomposed into a sum of a variable Z (common to both measures) and a residual specific to each measure. Under certain supplementary hypotheses, it is possible to estimate the common component along the seismic sections. Some complements to these studies are mentioned, for example the correspondence between geophysical and geostatistical methods or the consideration of uncertainty in the amplitudes
Baron, Louise. „Sea level changes in the Oxfordian stage of Britain and France“. Thesis, Imperial College London, 1997. http://hdl.handle.net/10044/1/7899.
Der volle Inhalt der QuelleScholtus, Nicolas. „Altération pédogénétique des argilites du Callovo-Oxfordien soumises à la végétalisation“. Vandoeuvre-les-Nancy, INPL, 2003. http://www.theses.fr/2003INPL056N.
Der volle Inhalt der QuelleHe, Zheng. „Quelques contributions à la modélisation micromécanique de l’argilite du Callovo-Oxfordien“. Thesis, Lille 1, 2012. http://www.theses.fr/2012LIL10166/document.
Der volle Inhalt der QuelleThis work focuses on the development of micromechanical modeling tools to study the behavior of the Callovo-Oxfordian argillite. This geomaterial is modeled as a porous heterogeneous medium at three distinct spatial scales. The microscopic scale reveals the heterogeneity of the clay phase on which the morphological model synthesized as a porous polycrystal was based. Numerical predictions of the elastoplastic and transversely isotropic clay phase considering mechanical interactions between the crystals are performed by using an incremental approach. Then, a poroelastic model for saturated granular materials with imperfect interface effects is proposed. On the basis of this poroelastic model and the nonlinear homogenization, we showcase the impact of the cohesive Mohr-Coulomb imperfect interfaces on the strength criterion of granular geomaterials. Finally, we propose a complete model for the prediction of the strength of Callovo-Oxfordian argillite under the assumption that the clay matrix is a porous material with the solid phase described by a perfectly plastic Drucker-Prager criterion. It is important to note that the explored failure mechanism includes the possibility of a strain concentration at the (rigid) inclusion-matrix interface. This model is analyzed in detail and its predictions appear quite convincing
Menaceur, Hamza. „Comportement thermo-hydro-mécanique et microstructure de l'argilite du Callovo-Oxfordien“. Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1167/document.
Der volle Inhalt der QuelleThe development of nuclear energy in recent years requires safe solutions for the storage of radioactive waste. A solution proposed for high activity radioactive waste is the storage indeep low permeability geological formations such as claystones. In this perspective, Andra, the French agency for the management of radioactive wastes, supported investigations on theshort and long term behaviour of the Callovo-Oxfordian (COx) claystone, considered as apotential host rock in France. In this framework, a microscopic and macroscopic experimental study on the thermo-hydro-mechanical behaviour of COx claystone was carried out. In this work, a microstructure investigation of the water retention properties of the Cox claystone was performed. The water retention properties were determined by controlling suction through the vapour phase, with also the monitoring of volume changes and changes indegree of saturation as a function of suction along the drying and wetting paths. The study was completed by a microstructure investigation based on the use of mercury intrusion porosimetry on freeze-dried specimens. It was observed that the concepts governing the hydration of smectites appeared useful to better understand the effects of changes in water content and suction on the microstructure of COx claystone. In a second step, the compression-swelling behaviour of the COx claystone was related to micro structure features by performing high pressure oedometer compression tests and byrunning mercury intrusion porosimetry tests and scanning electron microscope observationson specimens submitted to compression and stress release. The results obtained showed that the potential of swelling was linked to the density of cracks generated during compression. The thermo-mechanical behaviour of fully saturated COx claystone specimens was investigated from shear and drained heating tests using a hollow cylinder triaxial device specially developed for low permeability materials. The shear tests at 25°C evidenced lowershear strength on specimens with higher porosity. The preliminary results obtained at 80°Cevidenced a more ductile response, with slightly smaller shear strength and little changes of the elastic parameters at elevated temperature. Drained isotropic heating tests confirmed thecontracting volumetric plastic behaviour of the COx argillite, similar to normally consolidated clays. The effect of thermal pressurisation of the pore water on a specimen with a pre-existingshear plan was investigated. The results showed that undrained heating under shear stress decreased the effective stress, bringing back the sheared specimen to failure. The self-sealing properties of COx claystone at 25 and 80°C were investigated by conducting steady state permeability tests on sheared specimens at various stages. The results showed that the overall permeability of the sheared specimen at 25 and 80°C was comparable to that before shearing, confirming the good self-sealing properties of COx claystone
Cariou, Elsa. „La plateforme jurassienne au passage Oxfordien - Kimméridgien : dynamique sédimentaire et paléoenvironnements“. Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10099/document.
Der volle Inhalt der QuelleThe Upper Jurassic Jura platform separated the Paris basin and the delphino-helvetic basin. The scarcity of biostratigraphic fossils of the Oxfordian-Kimmeridgian platform deposits prevent from establishing accurate dating. The common organization and hieacrchy of depositional sequences observed in French and Swiss Jura and in Lorraine allow to establish high-resolution regional correlations, and show the involvement of eccentricity and precession cycles in the formation of sequences. Correlations allow revising the French Jura bio-lithostratigraphic framework and highlight the evolutions of platform geometry and palaeoenvironments. Isotopic analysis based on oyster and Trichites specimens, sampled in several beds from the Upper Oxfordian-Lower Kimmeridgian, in Jura and Normandie, show a similar climatic evolution, all around the Paris basin. This evolution seems closely linked to the Jura platform sedimentary dynamics. The study of the Upper Oxfordian reef entities shows that their compositions and morphologies depend on their position along the platform and the evolution of relative sea level. In the end of the Bimammatum zone, the record of dinosaur trackways, in the platform deposits, expresses an emersion phase. Its position in the sequential framework shows that the track record was abled by an exceptional palaeogeographic, palaeoenvironmental and sequential context that favored on the one hand the development, induration and covering of microbial laminites and on the other hand the migration of dinosaurs across the platform
Rivard, Camille. „Contribution à l'étude de la stabilité des minéraux constitutifs de l'argilité du Callovo-Oxfordien en présence de fer à 90° C“. Thesis, Vandoeuvre-les-Nancy, INPL, 2011. http://www.theses.fr/2011INPL090N/document.
Der volle Inhalt der QuelleIn the context of underground disposal of high-level radioactive waste, interactions between metallic iron and Callovo-Oxfordian rock (COx), its purified clay fraction (SCOx) or pure clay phases (kaolinite, illite, smectites) were investigated at 90°C under anoxic atmosphere in chlorine solution. Role of COx non clay minerals in these reactions was also studied. Rapid metallic iron oxidation conducts to iron cations release in solution, pH increase (8-10) and Eh decrease (reducive conditions). The partial dissolution of initial clay phases and the crystallization of Fe-serpentines (odinite or berthierine mainly) and of low amount of magnetite were observed. The introduction of O2 into the system leads to Fe-serpentines destabilisation. Iron exsolution conducts to iron oxides and hydroxides formation and clay particles with composition close to the initial ones precipitate. Addition of quartz into the system leads to the partial dissolution of this mineral and to the modification of reaction pathways. Precipitation of magnetite is reduiced and Fe-serpentines are silica enriched. In the case of kaolinite-metallic iron interaction, combinated used of XRD, MET, XPS and textural analyses evidences the growth of berthierine on the basal face of kaolinites, resulting in Fe-serpentine-kaolinite demixed particles. Through the used of spectroscopic analyses (Mössbauer, XAS and STXM), we were able to determine Fe2+/Fe3+ and AlIV/AlVI ratio in elementary particles, which allows proposing structural formulae for the Fe-serpentines
Mohajerani, Mehrdokht. „Etude expérimentale du comportement thermo-hydro-mécanique de l'argilite du Callovo-Oxfordien“. Phd thesis, Université Paris-Est, 2011. http://pastel.archives-ouvertes.fr/pastel-00647890.
Der volle Inhalt der QuelleLabelle, Daniel G. P. „Allostratigraphic analysis of the Upper Jurassic, Callovian-Oxfordian, Roseray Formation, southwestern Saskatchewan“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ30496.pdf.
Der volle Inhalt der QuelleDe, Wet Carol Birney. „Deposition and diagenesis of the Corallian Formation (Oxfordian) within the Wessex Basin“. Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315103.
Der volle Inhalt der QuelleMaia, Flávia Marina Serafim. „Impact de l'élévation de la temperature jusqu'à 80ºC sur le comportement des radionucléides dans le callovo-oxfordien : application à l'uranium“. Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2018. http://www.theses.fr/2018IMTA0078/document.
Der volle Inhalt der QuelleThe aim of this study was to understand and quantify the behaviour of U(VI) on the Callovo-Oxfordian(COx) clay which is envisioned to host high-level radioactive waste in France. The temperature effect up to 80°C on this behaviour was particularly studied. The first part of the work focussed on the thermodynamic properties of the calcium uranyl carbonate aqueous complexes which govern U(VI) speciation in solution. They were measured indirectly by sorption-based methodologies under controlled pCO₂ and pH. The results indicate that the temperature does not favour the formation of CaUO₂(CO₃)₃²⁻ (log₁₀ βº₁₁₃ = 27,3 ± 0,3 ; ΔrHº = -27,4 ± 8 kJ/mol) and does not affect the formation of Ca₂UO₂(CO₃)₃(aq)(log₁₀ βº₂₁₃ = 29,7 ± 0,3 ; ΔrHº = 0 ± 2 kJ/mol). A bottom-up approach with the published “2SPNE SC/CE”model was used for describing the sorption processes, with the assumption that the clay fraction of the COx (Illite, andI/S) governs U(VI) sorption.The model was successfully applied to reproduce a wealth of experimental data obtained with illite, the COₓ clay fractionand the COₓ clay rock as a function of key parameters (pH, pCO2, [U(VI)], [Ca]) at 20 °C. The sorption on COₓ conditions is mainly governed by the sorption of U(VI)-CO3 complexes and a new sorption constant is proposed for illite. An increase in temperature to 80 °C leads to an in-crease of U(VI) retention on COx. This increase is ac-companiedby a change of both pCO₂ and pH. The sorption model developed at 20 °C, together with the thermodynamic parameters describing U(VI) speciation in solution, can explain this increase but without obtaining a good agreement with the experiment. The model is improved by considering ΔrHº values for sur-face complexation reactions obtained for the U(VI))/illite system
Rasamimanana, Sabrina. „Rétention et transport diffusif d'anions organiques dans la roche argileuse du Callovo-Oxfordien“. Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066441.
Der volle Inhalt der QuelleThe Callovo-Oxfordian mudstone (COx) is studied as a possible host rock for a deep disposal of radioactive waste (Cigéo project). Indeed, besides being very weakly permeable, it presents a high content of clayey minerals, capable of retaining radionuclides under cationic form and to delay strongly their transport. Nevertheless, some waste packages may release a significant amount of organic molecules, capable of complexing these radionuclides and drastically increase their mobility. So, the objective of this work was to better understand the diffusive behavior of several organic molecules of interest in this mudstone, by investigating at first their affinity with the host rock. The retention of organic molecules under anionic form (acetate, phthalate, adipate, benzoate, and citrate) was quantified on to the dispersed COx mudstone using adsorption/desorption batch experiments. Experiments on decarbonated rock and clay fraction only (< 2µm) were also performed to identify solid phases and chemical functions responsible for the retention. A correlation of the intensity of retention, Rd, was pointed out whit the dipole moment µ(Orga.), providing a qualitative estimate of retention capacity for polar hydrophilic organic molecules. So, phthalate, slightly polar, displays a reversible retention (Rd ~1,6 L.kg-1), mainly on clayey phases. Citrate, very polar and strongly adsorbed (Rd ~ 40 L.kg 1), displays a persistent desorption hysteresis and an affinity to different solid phases (clayey minerals and minor oxides). Lastly, acetate, adipate and benzoate, weakly polar, display a lower affinity with rock (Rd < 0,2 L.kg-1). The diffusive behavior in compact rock of these organic anions was then studied. The effective diffusion coefficient and retardation factor values were quantified. The low diffusivity, [De/D0]ORGANIC ANIONS ~ 0,1 à 0,25 × [De/D0]WATER evidences an effect of anionic exclusion, with a same intensity as that observed for inorganic anions. Furthermore, the Kd adsorption coefficient, estimated from retarded diffusion are approximately 2 to 5 times lower than the Rd distribution coefficient measured on dispersed rock. This difference of behavior was not able to be attributed, or to kinetic effects, nor to accessible porosity to anions effects. Anyway, the complexing species display a significant diffusive retardation (Kd > 0,2 L.kg-1) consolidating the contain properties of the COx mudstone toward this species
Williams, Ann Cerys. „Palaeoecological and palaeoenvironmental variations in the Callovian, Oxfordian and Kimmeridgian (Jurassic) of Britain“. Thesis, University of Leicester, 1988. http://hdl.handle.net/2381/34984.
Der volle Inhalt der QuelleMarchand, Didier. „L'évolution des Cardioceratinae d'Europe occidentale dans leur contexte paléobiogéographique : Callovien supérieur, Oxfordien moyen“. Dijon, 1986. http://www.theses.fr/1986DIJOS026.
Der volle Inhalt der QuelleBregoin, Stéphanie. „Variabilité spatiale et temporelle des caractéristiques du Callovo-Oxfordien de Meuse/Haute-Marne“. Paris, ENMP, 2003. http://www.theses.fr/2003ENMP1297.
Der volle Inhalt der QuelleGuillon, Théophile. „Comportement hydromécanique des argilites du Callovo-Oxfordien lors de cycles de désaturation-resaturation“. Thesis, Vandoeuvre-les-Nancy, INPL, 2011. http://www.theses.fr/2011INPL101N/document.
Der volle Inhalt der QuelleThe Callovo-Oxfordian claystones’ properties make them reliable as a geological barrier for the confinement of radioactive wastes. In order to optimally predict their behavior, how they respond to various short and long terms loadings has to be studied. Particularly during the exploitation phase, air is continuously ventilated throughout the galleries. The climatic properties of this air are not balanced with those of the rock, and may perturb its hydromechanical (HM) attributes. Thus, assessing the HM response of the rock under hydric loading seems to be a priority.This dissertation begins with laboratory tests to propose an appropriate physical model. Drying tests were studied as they focus on the HM response of samples undergoing hydric loadings. A first 2D isotropic model is proposed, and then enhanced to 3D by considering a transversely isotropic Young modulus. Secondly, experimental results provide relevant data to estimate poroelastic and transport parameters involved in the model. Estimation is achieved according to an inverse procedure, which minimizes the error between measurements and model predictions. Finally, a real-size test is simulated using 2D models: an isotropic plastic one and a transversely isotropic elastic one.Model predictions reproduce well the laboratory tests data. When simulating the in situ behavior, a rather good agreement is obtained between the numerical and experimental results (although using the parameters estimated at the laboratory scale). However, the model highlights a limited influence of plasticity in the laboratory tests, while dissipative phenomena obviously occur in situ. 3D laboratory simulations do not improve the precision of 2D results, but reproduce more experimental data (mass variations, axial and lateral strains). Moreover, the inversion process is more efficient when ran over various kinds of data. Furthermore, stability of the algorithm is improved when adopting a two-phase convergence (simplex, followed by a gradient-like method). Numerical estimates of the parameters are in agreement with the direct experimental measurements obtained through other tests
Marchand, Didier. „L'Evolution des cardioceratinae d'Europe occidentale dans leur contexte paléobiogéographique (Callovien supérieur, Oxfordien moyen)“. Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37599443m.
Der volle Inhalt der QuelleHenderson, Andrew Scott. „The palaeo-ecology and biostratigraphy of the foraminifera from the Oxfordian of north Dorset“. Thesis, University of Plymouth, 1997. http://hdl.handle.net/10026.1/2002.
Der volle Inhalt der QuelleOxford, Melissa Jane. „Foraminiferal distribution and sequence stratigraphy of Oxfordian successions in the Wessex/Anglo-Paris Basin“. Thesis, University of Plymouth, 2004. http://hdl.handle.net/10026.1/2104.
Der volle Inhalt der QuelleAbou-Chakra, Guéry Ariane. „Contributions à la modélisation micromécanique du comportement non linéaire de l'argilite du Callovo-Oxfordien“. Lille 1, 2007. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2007/50376-2007-191.pdf.
Der volle Inhalt der QuelleThis work is performed in the general context of the project of underground disposal of radioactive waste, undertaken by the French National Radioactive Waste Management Agency (Andra). Due to its strong density and weak permeability, the formation of Callovo-Oxfordian argillite is chosen as one of possible geological barriers to radionuclides. The objective of the study to develop and validate a non linear homogenization approach of the mechanical behavior of Callovo-Oxfordian argillites. The material is modelled as a composite constituted of an elasto(visco)plastic clay matrix and of linear elastic or elastic damage inclusions. The macroscopic constitutive law is obtained by adapting the incremental method proposed by Hill. The derived model is first compared to Finite Element calculations on unit cell. It is then validated and applied for the prediction of the macroscopic stress-strain responses of the argillite at different geological depths. Finally, the micromechanical model is implemented in a commercial finite element code (Abaqus) for the simulation of a vertical shaft of the underground laboratory. This allows predicting the distribution of damage state and plastic strains and characterizing the excavation damage zone (EDZ)
Sun, Yufeng. „Time-dependent hydromechanical behaviour of callovo-oxfordian claystone by anatytical and multiscale numerical methods“. Electronic Thesis or Diss., Vaulx-en-Velin, École nationale des travaux publics de l’État, 2023. http://www.theses.fr/2023ENTP0009.
Der volle Inhalt der QuelleIn the context of radioactive waste repository, the time-dependent hydromechanical behaviour of the Callovo-Oxfordian (COx) claystone is investigated to ensure the safety conditions required for long-term repository of radioactive wastes.The first two parts of the study are based on the phenomenological approach carried out directly at the macroscale. Firstly, a quasi-analytical model for the hydromechanical behaviour of a deep spherical cavity excavated in a dilatant poro-viscoplastic rock mass is presented, considering three stages of a simplified life cycle: excavation, free convergence and post-closure. Subsequently, the sensitive and probability analyses are carried out using the finite element code Cast3M toinvestigate the time-dependent extent of the Excavation Damaged Zone (EDZ) which refers to a region characterized by significant and mainly irreversible changes in geochemical and hydromechanical properties. In the following, a multiscale numerical approach is employed to investigate its creep and damage behaviour under mechanical condition. Firstly, a micromechanics-based model within the finite element square (FE2) framework is developed to model the short-term and long-term behaviours of saturated COx claystone. For the viscous behaviour, two microscale mechanisms have been introduced: the viscoplasticity of the clay aggregates and the viscoelasticity of their contacts. Then, the creep model of COx claystones developed at small scale is applied to model the large-scale creep behaviour at laboratory and gallery scales. From simulation results of laboratory scale, a clear three-stage creep process is reproduced, including the primary creep stage, second creep stage and tertiary creep stage. At the gallery scale, the long-term effect of viscosity on the gallery convergences, the evolution of EDZ, and the long-term drainage and pore pressure around a gallery are investigated. Finally, the above developed double-scale creep model used to simulate saturated cracked medium is extend to partial saturated case to study the interaction between rock and the atmosphere occurs through air circulation within underground galleries. The emphasis is to study the effect of the gallery air ventilation on hydromechanical behaviour of host rock. The model predictions reproduce the drainage and desaturation kinetics of undisturbed and damaged rock
Diaz, Nathalie. „Modélisation prédictive de la migration des anions par description de la microstructure de la roche : application à l'argilite du Callovo-Oxfordien“. Paris 6, 2009. http://www.theses.fr/2009PA066035.
Der volle Inhalt der QuelleDidier, Mathilde. „Etude du transfert réactif de l'hydrogène au sein de l'argilite intacte“. Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00770176.
Der volle Inhalt der QuelleHSSAIDA, TOURIA. „Etude palynologique : kystes de dinoflagelles du jurassique (bathonien, callovien, oxfordien) du bassin de guercif (maroc)“. Rennes 1, 1990. http://www.theses.fr/1990REN10055.
Der volle Inhalt der QuelleTran, Tan Huy. „Contribution à l’établissement d’un modèle rhéologique thermo-hydro-chimio mécanique de l’argilite du Callovo-Oxfordien“. Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10179/document.
Der volle Inhalt der QuelleThe study aims to evaluate the radioactive waste storage structures in argillite Callovo- Oxfordien : The first part presents the model SC2D (Swelling Creep Diagenesis Damage) used to simulate the behaviour of argilite, this model is based on special hydro-mechanical characteristics of the argillite Callovo-Oxfordien; The second part shows the applications of SC2D model to describe anisotropic damaged areas around the excavated structures. These EDZ zones are determined when the damage coefficients are unitary and the discontinuities activate when damage coefficient reaches unity, damaged coefficients are calculated from an extension of Mazars by considering the extension deformation in the directions of diagenesi; the final part discussess the delayed effects around the structures after excavation; they are represented by the deformation velocity vectors whose amplitudes are governed by the level of damage and the deviatoric stress. The comparison between in situ convergence measurements and modeled results validates the deformation velocity vectors
Durce, Delphine. „Interactions et transfert de macromolécules organiques et de colloïdes dans l'argile nanoporeuse du Callovo-Oxfordien“. Nantes, 2011. http://www.theses.fr/2011NANT2008.
Der volle Inhalt der QuelleLow permeability Callovo-Oxfordian clay rock is under consideration as a possible host rock for long-term disposal of radioactive waste in a deep geological repository. Radionuclides move slowly in the Callovo-Oxfordian rock but complexation with colloidal species or organic macromolecules, naturally present in the pore solution or generated by storage, may enhance their migration. These colloidal and organic species can be retained by the clay through chemical interactions or physical immobilization (filtration). To increase the understanding of their mobility, batch and transport experiments (percolation) were performed on crushed and whole rock samples using Se(0) colloids and the following organic acids: succinic acid (118Da), citric acid (192Da) and polymaleic acid (1900Da). Adsorption studies on Se(0) colloids show the retention of this species on the clay. However, the properties of these colloids are masked by the presence of the protein required for the stabilization of the suspension. Adsorption studies on organic acids highlight the retention of these species (between 2. 2. 10-3 and 4. 20. 10-2 mol/kg of rock) which is strongly irreversible and which depends on the Ca2+ ion concentrations in solution and on the capacity of organic acids to complex with this ion. Percolation experiments performed on succinic and polymaleic acids show that despite their size, these molecules are mobile in the pore water of the compact rock. Filtration was not observed. Interactions rock/organic molecule were similar to those identified on a crushed rock
Aït-Ouméziane, Habiba. „Modalités évolutives et systématiques des genres Rhynchonelloidella Ivanoviella et Thurmanella (Brachiopodes Rhynchonellides) au Callovien et à l'Oxfordien“. Dijon, 1987. http://www.theses.fr/1987DIJOS002.
Der volle Inhalt der QuelleBrealey, Simon. „The late Oxfordian to Kimmeridgian history of the Rob Roy and Ivanhoe fields, Outer Moray Firth“. Thesis, University College London (University of London), 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.555873.
Der volle Inhalt der QuelleLe, Couls Matthieu. „Les paléoflores du Jurassique moyen et supérieur (Bathonien - Oxfordien) du bassin parisien et de ses marges“. Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1B045.
Der volle Inhalt der QuelleThe palaeoflora of Late and Middle Jurassic of the Paris basin is documented by a set of rather important outcrops, relatively little know, containing fossils of every type, mainly imprints often without cuticle, sometime with, or otherwise silicification in flint nodules. Eight historic or new outcrops were studied, plus four isolated fossils, all dating from the Bathonian-Oxfordian interval and distributed on the whole Paris basin and its margins. Three deposits were studied in the eastern part of the basin, its Arc-en-Barrois (late Bathonian), Étrochey (early and middle Callovian), and Laignes (middle Callovian). They all belong to the archipelago of the Burgundian platform, whose islands are covered by a mixed xerophytes Brachyphyllum forest. The deposit of Auxey, situated to the south, close to the city of Beaune, dated of late Oxfordian shows on the contrary a flora of wet environments, rich in ferns. Two others outcrops were studied close to the seuil du Poitou, the late Callovian flora of Sauzé-Vaussais and Poitiers surroundings, rich in bennettitales, presumably corresponding to relatively open xeromorphic environments. Finally, two last deposits were studied in the west of the basin, on the oriental margin of the emerged Armorican massif, the flora of the late Bathonian of Mamers and Nonant-le-Pin. These two outcrops correspond to a coastal mixed Brachyphyllum forest, also in a xeromorphic environment. Thereby, the Paris basin presents from Bathonian to Callovian exclusively xerophytes floras, corresponding to rather closed paleoenvironments, as on the Burgundian platform, to on the contrary opened enough environments, as in Poitou. The flora of internal environments, far from coasts, are not known for this period. In late Oxfordian on the other hand, the flora of Auxey would indicate rather a certain moistering of the climate, although more ample data are necessary to confirm this interpretation
Gaidon, Jean-Luc. „Minéralisations et structuration d'une marge continentale passive : l'exemple des concrétions tubulaires du bassin subalpin (Callovien-Oxfordien)“. Lyon 1, 1988. https://tel.archives-ouvertes.fr/tel-02290384/document.
Der volle Inhalt der QuelleShen, Wanqing. „Modélisations micro-macro du comportement mécanique des matériaux poreux ductiles : application à l'argilite du Callovo-Oxfordien“. Thesis, Lille 1, 2011. http://www.theses.fr/2011LIL10144/document.
Der volle Inhalt der QuelleThis work focused on the plasticity modeling of ductile porous materials. Different classes of porous media (with or without plastic compressibility of the matrix) are considered. Concerning the case of incompressible matrix obeying to the von Mises criterion, by using limit analysis combined with homogenization techniques, we obtained, a closed form expression of the macroscopic yield function for materials containing randomly oriented spheroidal cavities. An extension of the Gurson criterion is proposed for materials whose matrix is plastically compressible and obeys to an elliptic criterion. The obtained results are applied and illustrated in the case of double porous media. Then, an emphasis is put on porous geomaterials. The Callovo Oxfordian argilite, a geomaterial which is of a primary interest in this study, is modeled as a heterogeneous medium made, at the mesoscale, of a porous elastoplastic matrix and elastic inclusions. The micro-meso transition leading to the constitutive law of the clay matrix is performed for an associated or a non-associated Drucker-Prager solid phase and spherical cavities. The meso-macro transition is performed by means of a Hill incremental homogenization method. The predictive capabilities of the micro-macro model based on a non-associated solid phase have been demonstrated via a wide experimental validation. Finally, a simplified version of the micro-macro model is formulated by assuming rigid inclusions. The introduction of a macroscopic non-associated flow rule allows to obtain excellent predictions for the argillite
Lefrançois, Anne. „Étude de la variabilité sédimentaire dans le Callovo-Oxfordien de la bordure ardennaise du bassin parisien /“. [Fontainebleau] : École des mines de Paris, [Centre d'informatique géologique], 1998. http://catalogue.bnf.fr/ark:/12148/cb37066384q.
Der volle Inhalt der QuelleGaidon, Jean-Luc. „Minéralisations et structuration d'une marge continentale passive l'exemple des concrétions tubulaires du bassin subalpin, Callovien-Oxfordien /“. Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376137425.
Der volle Inhalt der QuelleLefrançois, Anne. „Etude de la variabilite sedimentaire dans le callovo-oxfordien de la bordure ardennaise du bassin parisien“. Paris, ENMP, 1995. http://www.theses.fr/1995ENMP0616.
Der volle Inhalt der QuelleBraun, Philipp. „Comportement thermo-hydro-mécanique de l´argilite du Callovo-Oxfordien : Effets des chemins de contrainte et des variations de température“. Thesis, Paris Est, 2019. http://www.theses.fr/2019PESC1004.
Der volle Inhalt der QuelleExtensive research is carried out by the French National Radioactive Waste Management Agency (Andra), in order to characterize the Callovo-Oxfordian (COx) claystone, a candidate host rock for a deep geological radioactive waste repository in France. The hydromechanical behaviour of the rock due to the excavation of the galleries are studied, as well as the thermo-hydro-mechanical (THM) response arising from heat generated by the exothermic waste packages. A laboratory programme was carried out in this work to characterize the response of COx claystone to different THM loadings within the framework of transversely isotropic thermo-poro-elasticity.Due to the very low permeability of the COx claystone, laboratory experiments have to be adapted for long saturation and drainage durations. Analytical solutions are presented for the time dependent pore pressure field in a specimen submitted to various loading paths and different rates. This provides a simple and efficient tool for the estimation of the conditions that must hold for reliable determination of material parameters. It allows as well an optimization of various test conditions.Based on this approach, a new transient step loading procedure was developed for isotropic tests in drained and undrained conditions, under both thermal and mechanical loading. This protocols render experiments on low permeable rocks more time efficient, giving access to several THM parameters and permeability measurements in a single test.In isotropic compression tests, pore pressure tests, and deviatoric loading tests parallel and perpendicular to the bedding plane, poroelastic properties were investigated on saturated rock specimens. The performed experiments provide compatible material parameters at different stress levels, evidencing a significant transverse isotropy, which had little effects on the back-calculated Biot’s coefficients and more effects on Skempton's coefficients.Thermal loads were exerted on COx specimens along different heating and cooling paths. Drained and undrained thermal expansion coefficients along both the transverse isotropic directions were determined. The measurement of pore pressure changes yielded the thermal pressurization coefficient, with a stress and temperature dependency identified.Thermo-hydro-mechanical loading paths corresponding to the paths expected in situ at the symmetry axis between two microtunnels, in which canisters are placed, were mimicked in the laboratory. Using a specially developed novel triaxial device, samples were heated with no radial strain allowed, until thermally induced pore pressures caused effective tensile stresses, which ultimately fractured the material at axial effective stresses around -3.0 MPa. Fracturing under different lateral total stresses allow to describe the failure with Fairhurst's generalized Griffith criterion. Using the THM properties evaluated earlier in the study, one is able to satisfactorily reproduce the observed deformations under tension.Last of all, a thermo-poroelastic model was implemented in the finite element solver Freefem++. The THM behaviour around parallel microtunnels in periodic layout is simulated in a 2D configuration. This helps to better understand the spatial arrangement of THM processes, heat and fluid transport, and the change of stress states with respect to the presented failure criterion
Abdulmajid, Mohamad. „Determination of the in-situ fracture properties of Callovo-Oxfordian rocks : application to the prediction of fracture networks geometry around tunnels“. Electronic Thesis or Diss., Sorbonne université, 2020. http://www.theses.fr/2020SORUS064.
Der volle Inhalt der QuelleThe use of nuclear energy requires safe solutions for the storage of radioactive waste. A solution proposed for high activity radioactive waste is the storage in deep low permeability geological formations such as claystones. In France, the feasability and safety of this solution is investigated in the Bure URL (Underground Research Lab) by Andra, the French agency for the management of radioactive wastes. Motivated by this challenge, we explore here the fracture properties of the Callovo-Oxfordian (COx) claystone present in Bure. Crack propagation is the main mechanism leading to material failure under traction. However, in anisotropic materials like claystone, the behavior of cracks both during their initiation and their propagation phase remains poorly understood. As a result, this work aims also at improving our understanding of the mechanisms of fracture in anisotropic materials, through the example of the COx claystone. In addition to that, the determination of the fracture properties of rocks in their in-depth conditions is a very diffcult challenge. We will show here that this diffculty can be overcome by analysing the roughness of the in-depth fractures. We will start this study by a systematic characterization of the fracture properties of the COx claystone from fracture tests performed in the laboratory. We will investigate both the crack propagation phase (through the measurement of the toughness in different directions of the material, for different water content levels) as well as the initiation phase (through the measurement of the cohesive strength in different directions too). We will then show how to measure these material parameters from a statistical analysis of the resulting fracture surfaces. In a second step, we will apply this newly developped method of material characterization to fractures produced during the excavation of the gallery and extracted in the URL at 490 m deep. This analysis will provide the fracture properties of COx claystone in in-situ conditions. Finally, the detailed characterization of the fracture properties of the COx claystone will be used in structural calculations to better understand the origin of the fractures located around the gallery. In particular, we will propose an original mechanism of tensile crack initiation under dominantly compressive loading conditions that allows us to capture the shape and size of the damaged zone observed around the gallery. On the long term, we believe that our work will help to the design of safer galleries dedicated to the storage of nuclear waste
Michel, Pauline. „Etude expérimentale des interactions organo-minérales de roches argilo-carbonatées : Application au Callovo-Oxfordien de la Meuse“. Université Louis Pasteur (Strasbourg) (1971-2008), 2006. http://www.theses.fr/2006STR1GE03.
Der volle Inhalt der QuelleSabau, Andrea. „Mécanismes d’interaction du nickel et de l´europium avec la calcite“. Thesis, Nice, 2015. http://www.theses.fr/2015NICE4003/document.
Der volle Inhalt der QuelleIn the context of the safety assessment of an underground repository for nuclear waste, sorption reactions are one of the main processes to take into account to predict the migration of the radionuclides. This work is focused on two elements: Eu(III) as an analogue of trivalent actinides and Ni(II) as activation product. Calcite was chosen as adsorbent due to its presence in Callovian-Oxfordian argillites. Our study combines batch experiments with spectroscopic techniques (TRLFS, RBS and SEM-EDXS) to elucidate the mechanisms occurring at Eu(III)/Ni(II) calcite interface. To obtain a better understanding on the systems, before starting sorption experiments, aqueous chemistry of Eu(III) and Ni(II) was carefully investigated. Macroscopic results showed a strong retention of Eu(III) on calcite, no matter the initial concentration, contact time and CO2 partial pressure. Ni(II) was also readily sorbed by calcite, but the retention was influenced by contact time and concentration. Time-dependent sorption experiments showed a marked and slow increase of retention upon a long time range (up to 4 months).Desorption results indicated a partly reversible sorption for Ni(II). TRLFS highlighted the influence of initial concentration and contact time on the interaction of Eu(III) with calcite. With the help of RBS and SEM-EDXS, it enabled to discriminate between different mechanisms like surface precipitation, inner-sphere complexation and incorporation. RBS showed incorporation of Eu(III) into calcite up to 250 nm, contrary to Ni(II) which was located at the surface