Dissertations / Theses: 'Salt deformation'

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Stormont, John Charles. "Gas permeability changes in rock salt during deformation." Diss., The University of Arizona, 1990. http://hdl.handle.net/10150/185159.

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A laboratory, field and numerical study of the changes in gas permeability which rock salt experiences during deformation is given. The laboratory tests involves gas permeability and porosity measurements coincident with hydrostatic and triaxial quasi-static, stress-rate controlled compression tests. The permeability and porosity of the as-received samples decrease significantly as a result of hydrostatic loading. These changes are largely irreversible, and are believed to "heal" or return the rock to a condition comparable to its undisturbed state. Deviatoric loading induces a dramatic change in pore structure. The permeability can increase more than 5 orders of magnitude over the initial (healed) state as the samples are loaded. The gas permeability changes are consistent with flow paths initially developing along the grain boundaries and then along axial secondary tensile cracks. The results from two sets of in situ gas permeability measurements from the underground workings of the WIPP Facility are given. The results consistently indicate that there is no measurable gas permeability prior to disturbing the rock by excavation. In the immediate vicinity of an excavation, the gas permeability can be 5 orders of magnitude greater than the undisturbed permeability. A numerical procedure to predict the in situ permeability is developed based on the results of the laboratory tests. The stress and strain fields surrounding excavations in rock salt, predicted with an elastoplastic model, are used in a model of gas permeability based on the equivalent channel model. The zone of the gas permeable rock is predicted well, but the magnitude of the gas permeability is underpredicted very near excavations. The gas permeability which develops in situ is principally a result of flow along dilated grain boundaries.

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Chemia, Zurab. "Modeling internal deformation of salt structures targeted for radioactive waste disposal." Doctoral thesis, Uppsala University, Department of Earth Sciences, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9279.

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This thesis uses results of systematic numerical models to argue that externally inactive salt structures, which are potential targets for radioactive waste disposal, might be internally active due to the presence of dense layers or blocks within a salt layer.

The three papers that support this thesis use the Gorleben salt diapir (NW Germany), which was targeted as a future final repository for high-grade radioactive waste, as a general guideline.

The first two papers present systematic studies of the parameters that control the development of a salt diapir and how it entrains a dense anhydrite layer. Results from these numerical models show that the entrainment of a dense anhydrite layer within a salt diapir depends on four parameters: sedimentation rate, viscosity of salt, perturbation width and the stratigraphic location of the dense layer. The combined effect of these four parameters, which has a direct impact on the rate of salt supply (volume/area of the salt that is supplied to the diapir with time), shape a diapir and the mode of entrainment. Salt diapirs down-built with sedimentary units of high viscosity can potentially grow with an embedded anhydrite layer and deplete their source layer (salt supply ceases). However, when salt supply decreases dramatically or ceases entirely, the entrained anhydrite layer/segments start to sink within the diapir. In inactive diapirs, sinking of the entrained anhydrite layer is inevitable and strongly depends on the rheology of the salt, which is in direct contact with the anhydrite layer. During the post-depositional stage, if the effective viscosity of salt falls below the threshold value of around 10¹⁸-10¹⁹ Pa s, the mobility of anhydrite blocks might influence any repository within the diapir. However, the internal deformation of the salt diapir by the descending blocks decreases with increase in effective viscosity of salt.

The results presented in this thesis suggest that it is highly likely that salt structures where dense and viscous layer/blocks are present undergo an internal deformation processes when these dense blocks start sinking within the diapir. Depending on size and orientation of these blocks, deformation pattern is significantly different within the diapir. Furthermore, model results applied to the Gorleben diapir show that the rate of descent of the entrained anhydrite blocks differs on different sides of the diapir. This suggests that if the anhydrite blocks descent within the Gorleben diapir, they initiate an asymmetric internal flow within it.

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Li, Shiyuan [Verfasser]. "Numerical studies of the deformation of salt bodies with embedded carbonate stringers / Shiyuan Li." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2013. http://d-nb.info/1034057251/34.

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Thiemeyer, Nicolas Verfasser], Gernold [Gutachter] [Zulauf, and Jörg [Gutachter] Hammer. "Microfabrics and deformation mechanisms of Gorleben rock salt / Nicolas Thiemeyer. Gutachter: Gernold Zulauf ; Jörg Hammer." Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2016. http://d-nb.info/1113107669/34.

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Thiemeyer, Nicolas [Verfasser], Gernold [Gutachter] Zulauf, and Jörg [Gutachter] Hammer. "Microfabrics and deformation mechanisms of Gorleben rock salt / Nicolas Thiemeyer. Gutachter: Gernold Zulauf ; Jörg Hammer." Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2016. http://d-nb.info/1113107669/34.

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Ferrer, Garcia J. Oriol. "Salt tectonics in the Parentis Basin (eastern Bay of Biscay): Origin and kinematics of salt structures in a hyperextended margin affected by subsequent contractional deformation." Doctoral thesis, Universitat de Barcelona, 2012. http://hdl.handle.net/10803/97042.

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The geological history of the north-Iberian margin and the eastern sector of the Bay of Biscay suggest that these areas are ideal places to study and characterize the tectonic evolution and the geodynamic mechanisms governing the opening of the Atlantic Rift. This fact can be seen very well since several evolutionary stages have been preserved within the rifting system along the North-Iberian Margin. Similarly, the study of these lateral variations also reveals how they conditioned the subsequent development of the Pyrenean orogen. At a more specific level, the Bay of Biscay appears as a good place to understand how the processes of mantle exhumation and subsequent mantle accretion occurred in the Atlantic Ocean, as well as to understand the role played by the resulting structures during the growth of the Pyrenean orogen. Furthermore, in its eastern sector, the Bay of Biscay allows the observation of the Mesozoic Parentis Basin slightly deformed by the Pyrenean compression. The study of this basin provides a first approach to understand how the Mesozoic basins were currently involved in the Pyrenean building previously to the Pyrenean compression (eg. Organyà Basin, Aulet Basin, etc…). These basins include highly deformed evaporitic materials from the Upper Triassic (Keuper facies) whose role during both the Mesozoic extension and the Cenozoic compression have been poorly studied. In this context, this thesis initially intended to elucidate how changes in the configuration of the crustal structure at the end of the Bay of Biscay opening have been able to control the change on structural style that took place from the Pyreness s.s. to the Cantabrian Pyrenees, to better understand the processes that governed the evolution of the Pyrenees. Second, at a smaller scale, this thesis aims to know which was the general structure of the Mesozoic intracontinental basins developed during the opening of the Bay of Biscay and which was its initial response during the Pyrenean compression. To achieve this goal we have analyzed several deep seismic surveys (ESCIN, ECORS and MARCONI) and the seismic data of the Parentis Basin. Apparently, the Mesozoic structure of this basin was slightly modified by the Pyrenean compression. In such asymmetric basin, salt tectonics has an important development and both its general structure and the salt structures have been poorly studied by the scientific community. In this sense, this thesis seeks to fill this gap pointing out the crustal fault structure of the Parentis Basin and establishing the style and the evolution of salt structures preserved in the basin. 1) Understanding the role played by the presence of a pre- or syn-kinematic salt level in the geometry and evolution of a thick-skinned extensional basin. 2) Determining the role played by the geometry of the main basin boundary faults in the formation of salt structures in its hangingwall during extension. 3) Investigating how salt structures developed during an extensional stage evolved with a subsequent contractional deformational stage which applied different degrees of shortening. The main results of the present thesis can be grouped into three action lines: 1) the characterization of structural variations along the Bay of Biscay-Pyrenean Rift System and its influence in the Pyrenean orogen development; 2) the definition of the Parentis Basin structure, in particular its western parts that were practically unknown; and 3) the analysis of the role played by the Upper Triassic pre-rift salt during both the extensional opening of the Bay of Biscay (specifically in the Parentis Basin) and the subsequent contractional development of the Pyrenean orogen.
Aquesta tesi pretén aclarir com els canvis en la configuració de l’estructura cortical al final de l’obertura del Golf de Biscaia van controlar els canvis en l’estil estructural que tenen lloc des dels Pirineus en sentit estricte fins als Pirineus Cantàbrics per tal d’entendre millor els processos que van governar l’evolució d’aquest orogen. A més, i a una escala més petita, intenta conèixer quina era l’estructura general de les conques intracontinentals mesozoiques que es van desenvolupar durant l’obertura del Golf de Biscaia i quina va ser la seva resposta inicial durant la compressió pirinenca. Per tal d’assolir aquests objectius s’han analitzat diverses campanyes de sísmica profunda (ESCIN, ECORS i MARCONI) així com de sísmica petroliera disponible a la Conca de Parentis. També s’han realitzat diversos models analògics per tal de recolzar les interpretacions realitzades. L’estructura mesozoica de la Conca de Parentis va ser lleument modificada per la compressió pirinenca. Cal remarcar que la tectònica salina va tenir un paper molt important en el desenvolupament d’aquesta conca. D’altra banda, tant la seva estructura general com les estructures salines no havien estat objecte d’estudi per la comunitat científica fins a la realització d’aquesta tesi. En aquest sentit doncs, aquesta tesi omple aquest buit posant especial interès en les estructures corticals que controlen el seu desenvolupament i estableix l’estil i l’evolució de les estructures salines preservades en ella. Els resultats principals de la tesi es poden agrupar en tres línies principals: 1) la caracterització de les variacions estructurals al llarg del sistema de rift Golf de Biscaia - Pirineus i la seva influencia en el desenvolupament de l’orogen pirinenc; 2) la definició de l’estructura de la Conca de Parentis i en particular del seu sector occidental; i 3) l’anàlisi del paper que va jugar la salt pre-rift del Triàsic Superior tant durant l’obertura del Golf de Biscaia (especialment a la Conca de Parentis), com durant el desenvolupament contractiu de l’orogen pirinenc.

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Jochems, Andrew P. "Formation, Deformation, and Incision of Colorado River Terraces Upstream of Moab, Utah." DigitalCommons@USU, 2013. https://digitalcommons.usu.edu/etd/1754.

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Fluvial terraces contain information about incision, deformation, and climate change. In this study, a chronostratigraphic record of Colorado River terraces is constructed from optically stimulated luminescence (OSL) dating of Pleistocene alluvium and real-time kinematic (RTK) GPS surveys of terrace form. This record is analyzed to relate terrace formation to late Pleistocene climate fluctuations, and terrain analyses and longitudinal profile patterns reveal recent salt-related activity in the northern Paradox Basin as well as patterns in Colorado Plateau incision. A well-preserved, correlative suite of mainstem (M) fluvial deposits exists along the Colorado River upstream of Moab, Utah. Absolute dates indicate sedimentation >70 ka (M7, M6/M5), 70-50 ka (M4), 50-40 ka (M3), and 35-25 ka (M2). The M4 and M2 formed during the crescendo to glacial maxima, but the M7, M6/M5, and M3 were deposited during variable climate of marine isotope stages (MIS) 5 and 3. Deposits include thin (<7 m) strath terraces and thick (10-20 m) fill terraces. Our results suggest that terrace sedimentation is linked to enhanced sediment flux during glaciations in Rocky Mountain headwaters (M4 and M2), but major deposits also formed during dryland tributary sediment loading with markedly different timing (M6/M5 and M3). Conversely, incision may be driven by higher deglacial flows. Clast provenance data demonstrate greater percentages of locally-sourced sediment in M6/M5 and M3 deposits. Valley-bottom geometry and neotectonics control terrace form, with strath terraces found in bedrock-restricted reaches and fill terraces in wider valleys. Previously speculated salt deformation in this area is confirmed by localized collapse preserved in M4 stratigraphy in the Cache Valley graben and ~15 m of broader subsidence upstream. Concavity and knickzone distributions in tributary profiles are discordant and represent subtle expressions of salt-tectonic activity. Finally, a surprisingly rapid incision rate of ~900 m/Ma over the past ~70 ka suggests that the Colorado River may be responding to flexural rebound in the central plateau, but is faster than that predicted by the debated bull's-eye pattern of regional incision. This locally high rate may also reflect a transient wave of incision, as suggested by increased Pleistocene rates interpreted by studies in Glen and Grand canyons.

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Bahroudi, Abbas. "The Effect of Mechanical Characteristics of Basal Decollement and Basement Structures on Deformation of the Zagros Basin." Doctoral thesis, Uppsala University, Department of Earth Sciences, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3394.

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Two fundamental structural elements, basement architecture and basal decollement, play a significant role in the evolution of a tectonically active region. Using different approaches (field data, literature review and analogue models) this thesis demonstrates that these two elements affected the deformation style in the Zagros fold-thrust belt during Mesozoic extensional and Cenozoic contractional episodes.

Reassessment of available data suggests a new configuration for the basement to Zagros basin that consists of basement faults with three different trends. Complicated interrelationships of these basement faults divide the Zagros basin into two major basement blocks, active and passive. This model associated with geological evidence suggests that deformation in the basement due to the convergence between Arabia and Iran is not restricted to the Zagros Mountains but already involves a considerable part of the Arabian platform. However, deformation in the cover units is not only governed by the deformation in the basement, which are decoupled from each other by the Hormuz salt in many parts in the Zagros fold-thrust belt.

Geological evidence shows that there is a clear relationship between activity of the Hormuz structures and the basement faults in the Zagros basin. Extended analogue models indirectly show how Hormuz types of basal decollement associated with the opening of Neo-Tethys can control the distribution, number, width and geometry of faults, penetrative strain, and diapirism. Analogue models shortened from one-end show that the spatial distribution of the Hormuz salt in the Zagros belt map viscous and frictional decollements to the thin-skinned deformation. Shortening of the cover results in formation of partitioning of strain into transpressional zones, different topographic wedges and differential sedimentation of growth sediments along the Zagros belt. Model results supported by geological and geophysical data sets suggest that some of the faults previously attributed to basement could have developed above the initial lateral boundaries between viscous and frictional basal decollements.

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Cook, Ethan L. "Near-Salt Stratal Geometries and Implications for the Evolution of the Onion Creek Diapir Moab, UT." BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6327.

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The Onion Creek Diapir is one of many salt domes proximal to the Uncompahgre thrust front of the ancestral rockies in the Paradox Basin. It is comprised of Paradox Formation evaporites and large blocks of Honaker Trail Formation carbonates that were deformed by loading of Permian Cutler Formation progradational alluvial to fluvial fans. The history of salt movement in the Onion Creek Diapir is recorded in the near-salt strata. Large salt bodies and their adjacent mini-basins evolve conforming to a complex relationship between salt withdrawal, creating localized accommodation, and sediment deposition. Migrating mini-basin depo-centers, thinned and folded strata, and spatial facies trends reveal the relative rates of diapirism and sedimentation. The study area outcrop, north of the diapir, is divided by significant stratigraphic horizons that help define depositional periods. Six measured sections in the study area reveal higher preservation rates of fine grained floodplain deposits, typically destroyed in alluvial environments, than at locations correlating to stratigraphic levels high in the outcrop suggesting a low accommodation environment evolving into higher accommodation where stacked channel complexes are preserved. Preserved slump folding at the base of the outcrop reveals that although some salt emergence occurred in the earliest depositional period it was not significant enough to preclude sediment deposition or to divert the Cutler fluvial network and destroy floodplain facies. A 3-D digital outcrop, modeled from photogrammetric data, illustrates the development of localized accommodation, attracting fluvial channel in a near-salt, tight axial syncline during the later depositional period. These evidences suggest a greater emergence of the diapir and likely diversion of the Cutler channel complexes.

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Mokni, Nadia. "Deformation and flow driven by osmotic processes in porous materials." Doctoral thesis, Universitat Politècnica de Catalunya, 2011. http://hdl.handle.net/10803/6279.

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En el caso del almacenamiento de los residuos radioactivos los flujos osmóticos pueden ser relevantes y requieren un análisis en detalle. El residuo nuclear bituminizado (BW) será almacenado mediante contenedores en cavidades excavadas en la Boom Clay, que es una arcilla marina que presenta propiedades favorables para limitar y retrasar la migración de los contaminantes radioactivos. La interacción entre los dos materiales es un proceso acoplado químico-hidro-mecánico y depende de la respuesta hidromecánica de la Boom Clay y del BW. En condiciones de almacenamiento, el contacto del BW, que contienen cantidades importantes de NaNO3, con el agua subterránea induce la hidratación por gradientes osmóticos y el consiguiente hinchamiento, además de la difusión de la sal disuelta hacia la Boom Clay. Se pueden distinguir dos tipos de afecciones: la perturbación geomecánica causada por el hinchamiento del BW y el aumento de presión en el BW y cambio de las distribución de tensiones en la roca, y la perturbación físico química por la migración de grandes cantidades de sales. El objetivo de esta tesis es: (i) Mejorar la comprensión de los procesos que controlan la absorción de agua y el consecuente hinchamiento del BW que contengan sales (NaNO3), y (ii) Investigar los posibles efectos de la concentración de fluidos de los poros sobre el hinchamiento, la compresibilidad y comportamiento de corte de la Boom Clay. En primer lugar, se ha desarrollado una formulación para el análisis de la deformación inducida por la disolución de sales en medio poroso con contacto con agua. Las ecuaciones planteadas incluyen los flujos acoplados de agua y soluto. Se presenta también un trabajo teórico que ayuda a la comprensión del comportamiento mecánico del BW. Se considera este material como una mezcla de bitumen y cristales de NaNO3. Se ha desarrollado un modelo elasto-viscoplástico que describe el comportamiento de fluencia del BW considerando el comportamiento de fluencia de sus constituyentes. El modelo constitutivo elasto-viscoplástico ha sido implementado en el programa CODE_BRIGHT. Los resultados se han comparado con observaciones experimentales. Se ha estudiado el comportamiento a largo plazo del BW en contacto con agua al simular ensayos de hinchamiento por absorción de agua bajo condiciones confinadas. El análisis numérico ha demostrado ser capaz de proporcionar una representación satisfactoria de los principales patrones observados en su comportamiento. En lo que respecta al segundo objetivo de la tesis, se ha propuesto una formulación para el análisis de las deformaciones inducidas por procesos osmóticos en un medio poroso de doble estructura. Esta formulación distingue dentro del material un nivel micro-estructural y otro macro-estructural con cambios químicos que tienen un efecto significativo en la micro-estructura. Se han obtenido las ecuaciones básicas que describen los flujos acoplados de agua y solutos y el transporte de sus componentes a través de los macroporos así como las ecuaciones de balance de masa para agua y soluto en los macroporos y microporos. La formulación propuesta ha sido aplicada particularmente para analizar cualitativamente el efecto de la succión osmótica sobre el hinchamiento de los suelos arcillosos. Se han analizado los efectos a corto y largo plazo. Se ha investigado también la influencia del aumento de la concentración del fluido en los poros sobre las propiedades geotécnicas y el comportamiento de la Boom Clay no saturada. Se ha llevado a cabo un programa sistemático de investigación experimental, con control de succión osmótica y matricial, con el fin de investigar el efecto del incremento de la concentración del fluido de poros sobre la resistencia de corte y el cambio volumétrico bajo condiciones edométricas. Se ha observado, que bajo condiciones parcialmente saturadas, un cambio en la salinidad provoca una disminución en la compresibilidad y en la resistencia de corte del material.
For deep storage of high-level nuclear waste osmotic flows can be significant and so require a careful analysis. In Belgium, The bituminized nuclear waste (BW) named Eurobitum contained in metallic drums will be placed inside a tunnel or a shaft excavated in the Boom Clay, which is 100 m thick marine clay presenting favourable properties to limit and delay the migration of the leached radionuclides over extended periods of time. In Geological disposal conditions, contact of the bituminized radioactive waste which contains high amounts of highly soluble salt (NaNO3) with groundwater will result in water uptake and swelling of the waste and in subsequent diffusion of the dissolved salt through the host clay formation. Basically, two types of disturbance can be distinguished: A geo-mechanical perturbation, caused by the swelling of the waste and the increase of the pressure in and around the waste and a physico-chemical perturbation by the release of large amounts of NaNO3 and other soluble salts. In this context the aim of this thesis is: (i) to improve the understanding of the processes controlling the water uptake and the subsequent swelling of bituminized waste containing soluble salts (NaNO3), and (ii) to investigate of the possible effects of the increase of pore fluid concentration on swelling, compressibility and shear behaviour of Boom Clay. A formulation has been proposed for the analysis of deformation induced by dissolution of salts in porous media in contact with water. The equations include the effect of coupled transport phenomena and the formulation has been included as an extension in the coupled THM program CODE_BRIGHT. A theoretical and experimental work aiming at understanding the mechanical behaviour of the Bituminized Waste has been presented.This material is considered for this purpose as a mixture of bitumen and crystals of NaNO3. An elasto-viscoplastic model has been developed that describes the creep behaviour of BW considering the constituents' creep behaviour. The elasto-viscoplastic constitutive model has been implemented into CODE_BRIGHT. The modelling results have been compared with the experimental data. The impact of osmotic forces on the swelling of the material has been investigated by simulating water uptake swelling tests under confined conditions and comparing the predictions with experimental results. The numerical analysis has proven to be able to furnish a satisfactory representation of the main observed patterns of the behaviour. In regard to the second objective of this thesis, a formulation has been proposed for the analysis of deformations induced by osmotic processes in double structure porous media. The formulation is based on the distinction within the material of a microstructural and a macrostructural levels with chemical changes having a significant effect on the microstructure. A macroscopic description of the system is provided. Then the basic equations describing coupled flows of water and solutes and the transport of its components through macropores and mass balance equations for water and solute in macro and micro pores have been obtained. The proposed formulation has been particularly applied to analyze qualitatively the effect of osmotic suction on swelling of clayey soils. Transient and long term effects have been analyzed. The influence of pore fluid concentration on the geotechnical properties and behavior of Boom Clay under partially saturated conditions has been investigated. A systematic experimental research program involving osmotic suction and matric suction controlled experiments has been carried to investigate the effect of the increase of pore fluid concentration on shear strength and on the volume change behaviour under odometer stress state conditions. It has been observed that under partially saturated conditions a change in salinity causes a decrease in compressibility and shear strength.

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Raith, Alexander Sascha Frank Verfasser], Janos [Akademischer Betreuer] [Urai, Christopher J. [Akademischer Betreuer] Spiers, and Christopher A. L. [Akademischer Betreuer] Jackson. "Internal deformation of salt bodies with large mechanical contrast: a case study of the Veendam salt Pillow, the Netherlands / Alexander Sascha Frank Raith ; Janos Urai, Christopher J. Spiers, Christopher A.-L. Jackson." Aachen : Universitätsbibliothek der RWTH Aachen, 2017. http://d-nb.info/1171818467/34.

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Raith, Alexander Sascha Frank [Verfasser], Janos [Akademischer Betreuer] Urai, Christopher J. [Akademischer Betreuer] Spiers, and Christopher A. L. [Akademischer Betreuer] Jackson. "Internal deformation of salt bodies with large mechanical contrast: a case study of the Veendam salt Pillow, the Netherlands / Alexander Sascha Frank Raith ; Janos Urai, Christopher J. Spiers, Christopher A.-L. Jackson." Aachen : Universitätsbibliothek der RWTH Aachen, 2017. http://d-nb.info/1171818467/34.

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Fuchs, Lukas. "Strain quantifications in different tectonic scales using numerical modelling." Doctoral thesis, Uppsala universitet, Mineralogi, petrologi och tektonik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-280759.

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This thesis focuses on calculation of finite and progressive deformation in different tectonic scales using 2D numerical models with application to natural cases. Essentially, two major tectonic areas have been covered: a) salt tectonics and b) upper mantle deformation due to interaction between the lithosphere and asthenosphere. The focus in salt tectonics lies on deformation within down-built diapirs consisting of a source layer feeding a vertical stem. Three deformation regimes have been identified within the salt: (I) a squeezing channel flow underneath the overburden, (II) a corner flow underneath the stem, and (III) a pure channel flow within the stem. The results of the model show that the deformation pattern within the stem of a diapir (e.g. symmetric or asymmetric) can reveal information on different rates of salt supplies from the source layer (e.g. observed in Klodowa-diapir, Poland). Composite rock salt rheology results in strong localization and amplification of the strain along the salt layer boundaries in comparison to Newtonian rock salt. Flow and fold structures of passive marker lines are directly correlated to natural folds within a salt diapir. In case of the upper mantle, focus lies on deformation and resulting lattice preferred orientation (LPO) underneath an oceanic plate. Sensitivity of deformation and seismic anisotropy on rheology, grain size (d), temperature (T), and kinematics (v) has been investigated. The results of the model show that the mechanical lithosphere-asthenosphere boundary is strongly controlled by T and less so by v or d. A higher strain concentration within the asthenosphere (e.g. for smaller potential mantle temperatures, higher plate velocities, or smaller d) indicates a weaker coupling between the plate and the underlying mantle, which becomes stronger with the age of the plate. A Poiseuille flow within the asthenosphere, significantly affects the deformation and LPO in the upper mantle. The results of the model show, that deformation in the upper mantle at a certain distance away from the ridge depends on the absolute velocity in the asthenosphere. However, only in cases of a driving upper mantle base does the seismic anisotropy and delay times reach values within the range of natural data.

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Küster, Yvonne [Verfasser], Bernd [Akademischer Betreuer] Leiss, Helmut [Akademischer Betreuer] Klein, and Bent T. [Akademischer Betreuer] Hansen. "Bromide characteristics and deformation mechanisms of naturally deformed rock salt of the German Zechstein Basin / Yvonne Küster. Gutachter: Helmut Klein ; Bent T. Hansen ; Bernd Leiss. Betreuer: Bernd Leiss." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2011. http://d-nb.info/1042264775/34.

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Salmazo, Eduardo 1980. "Modelagem matemática da evolução de domos salinos sua influência na perfuração de poços de petróleo." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263224.

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Orientador: José Ricardo Pelaquim Mendes
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências
Made available in DSpace on 2018-08-22T11:39:24Z (GMT). No. of bitstreams: 1 Salmazo_Eduardo_M.pdf: 7818535 bytes, checksum: a2f7369fd589c6f6e85ce6c997e8c112 (MD5) Previous issue date: 2013
Resumo: Neste trabalho discute-se os desafios associados à atividade de perfuração de poços de petróleo através de formações afetadas pela presença de domos salinos. Domos salinos podem induzir grandes tensões nas formações subjacentes e adjacentes, impondo a necessidade de um planejamento específico para a perfuração e manutenção de poços de petróleo. Durante a perfuração, em frente à zonda de sal, há relatos de problemas de aprisionamento de coluna, dissolução de sal no fluido de perfuração, ocasionando a formação de batentes mecânicos e cavernas. Há ainda, nas formações que rodeiam um domo salino, devido à alterações no campo de tensões, problemas de instabilidade nas paredes do poço aberto e formação de zonas anormalmente prossurizadas. Após o revestimento do poço, há casos de colapso do revestimento. Para prever e mitigar os riscos associados à essa atividade é de fundamental importância o entendimento dos fenômenos físicos que o ocasionam. Com essa finalidade, foi feito um estudo à respeito de tais mecanismo físicos como fluência e instabilidade hidrodinâmica, mais especificamente a instabilidade de Rayleigh-Taylor. Desenvolveu-se, a partir de tal estudo, um modelo analítico para prever o desenvolvimento de um domo salino e discutiu-se a forma como este pode interferir em parâmetros importantes para a atividade de perfuração como, por exemplo, o campo de tensões nas formações adjacentes às camadas de sal
Abstract: In this present work are discussed the challenges associated with the drilling activities in oil wells through formations affected by the presence of salt domes. This geological structures can induce large stresses in the underlaying and adjacent formations, imposing the necessity of specific planning for drilling and maintenance of such oil wells. During drilling, facing the salt, there are reports of problems of stuck pipe, salt dissolution, forming mechanical stops and caves. There are still, in formations around a salt dome, due changes in the stress field, problems of well instability and abnormally pressure zones. After casing, there are cases of case collapse. To prevent and mitigate risks associated to this activity, is crucial understand the physical phenomena behind it. With such finality, was made an study related with such physical mechanisms, such hydrodynamic instability, specifically the Rayleigh-Taylor instability. Was developed, from this study, an analytical model to predict the salt dome development and was discussed the way such it can interfer in important paramenters related to the drilling activity as, for exemple, the tension field in the formation around the salt dome
Mestrado
Explotação
Mestre em Ciências e Engenharia de Petróleo

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Marsh, Nicola A. "The influences of crustal extension, salt tectonics and gravity-driven deformation on the structural evolution of the Halten Terrace, offshore mid-Norway : new sights from 3D seismic data and fault analysis." Thesis, Durham University, 2008. http://etheses.dur.ac.uk/1933/.

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Normal fault zones play a fundamental role in the development of sedimentary basins and in the migration and trapping of hydrocarbons. The idealised geometry of an isolated post-sedimentary normal fault (Barnett, 1987, Walsh & Watterson, 1989) existing conceptual models that describe the process of fault growth and linkage in brittle systems (Childs et al, 1995; Cartwright et al, 1996; Childs et al, 1995, 1996b; Huggins et al, 1995), where fault planes composed of many overstepping segments are linked by areas of complex deformation called relay ramps, are generally accepted. Relay zones can trap significant volumes of hydrocarbon or act as leakage points, thus understanding the style of fault linkage, which strongly influences the location of hydrocarbon tops and reservoir compartmentalisation, is vital for any petroleum system.

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Kazadi, Banza Samuel-Barry. "Structural geology of the Kinsevere Copper Deposit, DRC." Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/24753.

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The Kinsevere mine is a copper deposit located in the Democratic Republic of Congo (DRC), within the Central African Copperbelt. This area is situated in the Katangan basin within the SE portion of the Lufilian Arc, which is a large, arcuate structure that extends from SE Angola, across the DRC, and into NW Zambia. The purpose of this study is to characterise the brittle deformation observed around the Kinsevere copper deposit to lead to an understanding of the deformation history of the area. This is accomplished by analysing fault-slip and fold data to help understand the relationship between regional palaeostress, faulting and folding present in the mine vicinity. This study also attempts to characterise fracture-controlled copper mineralisation within the interpreted geodynamic context of the area. The broader objective of this study is to relate the structural observations from Kinsevere to the deformation history of the Lufilian Arc. This study uses the right dihedral method to analyse four categories of brittle structures. The structural types analysed include slickensided faults, mineralised joints, and unmineralised joints and shear fractures. The data suggests that the palaeostress associated with the formation of brittle structures in the Kinsevere area occurred during three deformation events. The first event is characterised by a compressional stress regime which occurred during the early stage of the Kolwezian phase (D1). The second event is characterised by a strike-slip stress regime that formed as the result of clockwise rotation of the earlier (D1) compressional regime. Two fault-slip vectors were observed on the strike-slip fault planes, indicating that a reactivation occurred during the Monwezian phase (D2). The final structural event was characterised by the development of an extensional stress regime. This was associated with North-South oriented extension and is related to the East African Rift System (D3). These interpreted events correlate well with the geodynamic context related to the Lufilian orogeny. Another line of evidence that supports this structural interpretation is the presence of evaporitic minerals observed in the stratigraphic units surrounding the brecciated zones such as the RAT and the CMN. The structural association of these evaporitic minerals may be related to pre-existing, salt-bearing units, which were dissolved during an early compressive (D1) phase of the Lufilian orogeny. However, the contact between the Grey RAT and the Red RAT (distal from the breccia zones) does not show any evidence of faulting, and in the Kinsevere area the Grey RAT is always observed above the Red RAT. This suggests that the Grey RAT may be the uppermost stratigraphic unit of the RAT subgroup, which contradicts some previously published interpretations. Thus, the current structural architecture was probably formed from a combination of two separate mechanisms, including compression-related salt extrusion and the development of thrust faults and folding resulting from the shortening of the Katangan basin. Based on an analysis of the fracture-controlled mineralisation in the study area, it is shown here that most of the stress tensors indicate that these fractures were induced within the compressional stress regime generated by the Lufilian orogeny. This conclusion supports studies which suggest a multiphase origin for the mineralizing fluids active in the Katangan basin. Thus, the age of the copper mineralisation associated with fractures is interpreted to correlate with the timing of the folding event that occurred during the Lufilian orogeny between 540-550Ma.
Dissertation (MSc)--University of Pretoria, 2012.
Geology
unrestricted

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Morel, Jacques. "Experimental investigation into the effect of stress on dissolution and growth of very soluble brittle salts in aqueous solution." [S.l. : s.n.], 2000. http://ArchiMeD.uni-mainz.de/pub/2000/0098/diss.pdf.

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Aletto, Angela, and Sofia Engström. "Differentialsättningar i höga byggnader mellan vertikalt bärande element av stål och betong : Tidsberoende deformationer i element av betong på grund av lasthistorik, krypning, krympning och elastisk deformation samt elastisk deformation i stålpelare." Thesis, KTH, Byggvetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-174073.

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I höga hus, i storleksordningen 100 m och högre, med vertikalbärande stomme av stål och betong kan differentialsättningar uppstå då de olika materialen deformeras olika. Detta ger med tiden lutande bjälklag. I det här arbetet har ett beräkningsprogram tagits fram med hjälp av Mathcad för att räkna ut de slutliga deformationerna och hur mycket man behöver kompensera för skillnaderna i deformation genom att gjuta bjälklagen med fall. Programmet är tänkt att användas av WSP i projekteringen av höga hus. Med hjälp av programmet har parametriska studier gjorts och det visade sig att genom att ändra på vissa parametrar kan differentialsättningarna utjämnas. I vissa fall kan detta medföra att gjutning med fall ej är nödvändigt.
When high buildings are built with steel and concrete collaborating, some problems may occur because the materials deform differently. The differences in the final deformations make horizontally casted floors start to lean over time. In this study a program has been developed in Mathcad to calculate the final deformations and differences. The differences can then be compensated by casting the floor with a slope. The program is supposed to be used by WSP to project high buildings. The program has been used for some parametric studies to show how different parameters can decrease the differences. If this makes the differences small enough it will not even be necessary to cast floors with a slope.

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Olivella, Pastallé Sebastià. "Nomsothermal multiphase flow of brine and gas through saline media." Doctoral thesis, Universitat Politècnica de Catalunya, 1995. http://hdl.handle.net/10803/6261.

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Presentamos una formulación nueva para el análisis de problemas Termo-hidro-mecánicos en medios salinos. Esta formulación incluye, desde la obtención de ecuaciones de balance de masa, momento y energía hasta su resolución numérica, incluyendo la derivación de algunas ecuaciones constitutivas. El programa de calculo resultante (Code Bright) puede usarse para analizar problemas reales de sistemas de sellado construidos con agregados porosos de sal, que era la motivación original de este trabajo.

Las ecuaciones de balance se han formulado teniendo en cuenta que en un medio salino existen tres especies o componentes mayoritarios. Estos son: la sal, el agua y el aire. Uno de los aspectos diferenciadores respecto a otros medios geológicos es que la fase sólida se disuelve a concentraciones elevadas en la fase liquida a la que se llama Salmuera. Otro aspecto interesante es la presencia de inclusiones de salmuera en la fase sólida. La disolución y precipitación de la sal da lugar a un mecanismo de deformación por fluencia. La forma de los granos de sal cambia por disolución en las zonas donde se concentran las tensiones y recristalizacion en las zonas de menor estado tensional. Además los granos también se deforman por el carácter muy dúctil del propio sólido cristalino. Hemos derivado una nueva ley constitutiva tensión deformación para los agregados porosos de sal, que se basa en acoplar una geometría idealizada de los granos con los mecanismos fundamentales de deformación.

Una vez que se ha desarrollado y verificado el programa de cálculo, este ha sido aplicado para el estudio de diferentes fenómenos. Presentamos el análisis de las variaciones de porosidad inducidas por gradientes de temperatura en agregados porosos de sal no saturados. Las diferencias de temperatura inducen un flujo de vapor que es contrarrestado por un flujo de salmuera. Este arrastra la sal disuelta y da lugar a un flujo de sal hacia zonas de temperatura más alta.

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Günther, Ralf-Michael. "Erweiterter Dehnungs-Verfestigungs-Ansatz." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2010. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-27196.

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Gegenstand der Dissertation ist die Entwicklung eines Stoffmodells für duktile Salzgesteine, mit dem alle drei Kriechphasen, abhängig von einem inneren Zustandsparameter, beschrieben werden können. Die Modellierung der Schädigungs- bzw. Dilatanzentwicklung und deren Rückkopplung auf das Kriechverhalten ist das Kernstück der Stoffmodellentwicklung. Es wird eine Beziehung abgeleitet, die die Dilatanzentwicklung abhängig vom Manteldruck und der spezifischen Formänderungsarbeit beschreibt. Durch diese Formulierung und deren Verknüpfung mit dem o. g. Zustandsparameter lassen sich tertiäres Kriechen, Kriechbruch, Nachbruchverhalten und Restfestigkeit geschwindigkeitsabhängig beschreiben. Es erfolgte eine Validierung des Modells anhand von Laboruntersuchungen. Weiter wurden Parametersätze für zwei unterschiedliche Steinsalztypen abgeleitet. Anhand von drei realen Problemstellungen konnte gezeigt werden, dass das gemessene In-situ-Verhalten mit dem Modell berechnet werden kann und Prognoseberechnungen zu plausiblen Ergebnissen führen.

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Günther, Ralf-Michael. "Erweiterter Dehnungs-Verfestigungs-Ansatz: Phänomenologisches Stoffmodell für duktile Salzgesteine zur Beschreibung primären, sekundären und tertiären Kriechens." Doctoral thesis, TU Bergakademie Freiberg, 2009. https://tubaf.qucosa.de/id/qucosa%3A22710.

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Gegenstand der Dissertation ist die Entwicklung eines Stoffmodells für duktile Salzgesteine, mit dem alle drei Kriechphasen, abhängig von einem inneren Zustandsparameter, beschrieben werden können. Die Modellierung der Schädigungs- bzw. Dilatanzentwicklung und deren Rückkopplung auf das Kriechverhalten ist das Kernstück der Stoffmodellentwicklung. Es wird eine Beziehung abgeleitet, die die Dilatanzentwicklung abhängig vom Manteldruck und der spezifischen Formänderungsarbeit beschreibt. Durch diese Formulierung und deren Verknüpfung mit dem o. g. Zustandsparameter lassen sich tertiäres Kriechen, Kriechbruch, Nachbruchverhalten und Restfestigkeit geschwindigkeitsabhängig beschreiben. Es erfolgte eine Validierung des Modells anhand von Laboruntersuchungen. Weiter wurden Parametersätze für zwei unterschiedliche Steinsalztypen abgeleitet. Anhand von drei realen Problemstellungen konnte gezeigt werden, dass das gemessene In-situ-Verhalten mit dem Modell berechnet werden kann und Prognoseberechnungen zu plausiblen Ergebnissen führen.

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Hassoun, Virginie. "Analyse multi-échelles des déstabilisations sous-marines de la Marge Ligure : implications sur la répartition spatio-temporelle des facteurs déclenchant [sic]." Thesis, Nice, 2014. http://www.theses.fr/2014NICE4069.

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La marge Ligure est une marge passive soumise à une déformation tectonique compressive associée à la tectonique salifère messinienne. La reprise en compression de la marge s’accompagne d’une sismicité modérée récurrente ponctuée d’évènements plus forts. La marge Ligure est le siège d’une sédimentation importante au Plio-Quaternaire. Elle constitue un environnement propice à l’étude des déstabilisations gravitaires. L’objectif principal de ce travail était de décrire et caractériser les principaux mouvements en masse ayant affecté la marge continentale Ligure au cours du Plio-Quaternaire, de localiser les principales zones sujettes aux déstabilisations et d’identifier les facteurs pré-conditionnant et déclenchant les ruptures dans le but de mieux évaluer l’aléa gravitaire. Une large couverture de données bathymétriques, géophysiques et des carottages acquis sur l’ensemble de la marge a permis de réaliser une étude multi-échelles des processus de ruptures gravitaires et des facteurs déclenchant associés. Près de 1500 glissements ont été identifiés. L’étude de leur répartition spatio-temporelle illustre que l’ensemble de la marge a toujours été affectée par des déstabilisations de pente mais que les principales zones de ruptures auraient migré vers l’ouest au cours du Plio-Quaternaire. Les grandes ruptures sous-marines sont préférentiellement associées aux zones de déformation maximale, cette dernière étant contrôlée par la tectonique crustale et/ou la tectonique salifère. Il apparaît que les ruptures résultent plus généralement d’une association de facteurs distincts qui ont participé à fragiliser la stabilité des dépôts de la pente et qui ont pu provoquer leur rupture
The Ligurian margin is a passive margin characterized by high sedimentation rates during the Plio-Quaternary. It is affected by a compressive tectonic deformation leading to the inversion of the margin, together with a salt tectonic. The present-day moderate seismic activity is punctuated by stronger seismic events. Thus, this margin offers a good natural laboratory to study submarine landslides and their triggering factors. Although the Var Turbidite System has been well investigated over the last 20 years, the morphology and tectonics/sedimentary processes affecting the whole margin remained poorly known. This study aims to describe and to characterize the main types of mass movements, their preferential locations along the Ligurian margin during the Plio-Quaternary and their triggering factors to improve geohazards assessment related to landslides. A dataset including bathymetric and geophysical data and cores allowed to realize a multi-scale study of submarine failures and their associated triggering factors. About 1500 landslides were identified on the margin and in the basin. The study of their spatio-temporal distribution revealed that the margin has always been affected by mass-wasting processes and that the main zones of landsliding migrated westward during the Plio-Quaternary. The largest submarine landslides are preferentially associated with the highest deformation rates and their location is controlled by crustal tectonics and/or salt tectonics. The initiation of failures results from the combination of several factors including the margin deformation, earthquakes, salt tectonics and sediment under-consolidation

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Elgerud, Freja, and Isabel Sandström. "Infästningar för korslimmat trä : Tänkbara infästningar för ett 22-våningshus i KL-trä samt deras styvheters betydelse för de horisontella deformationerna." Thesis, KTH, Byggteknik och design, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-213953.

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Intresset för flervåningshus i trä ökar stadigt. Trä är ett lätt och mjukt material vilket är problematiskt med avseende på stomstabilisering och horisontella deformationer. Syftet har varit att undersöka förbandstyper för KL-trä och huvudfrågan var hur stommens horisontella deformationer påverkas av infästningstyperna och deras styvhet. En jämförande studie av självborrande skruvar och beräkning av deras förskjutningsmodul har utförts. En modell på 22 våningar med en stomme av KL-trä modellerades i RFEM. Analyser genomfördes för olika värden på förskjutningsmodul för att kunna jämföra de horisontella deformationerna. Resultatet visade på att deformationerna blev små och att skillnaden mellan olika förskjutningsmoduler gav en knappt märkbar skillnad i horisontell deformation, trots att variationen av värdet på förskjutningsmodulerna var stor. Detta kan förklaras av att modellen i sig är väldigt stabil, vilket främst skulle kunna bero på fasadelementens vertikala förskjutning och höjd. Andra bidragande orsaker var att modellen saknade urtag för dörrar och fönster, KL-elementens tjocklek samt att pågjutning av betong applicerades på varje våning.
The interest for multi storey buildings with timber is growing. Timber is a material that is light and ductile, characteristics that make timber a challenging material in terms of horizontal stabilization and horizontal displacements. The purpose was to examine connectors for CLT and the main question was how the horizontal displacement of the frame is affected by the connectors and their stiffness. A parametric study for self-tapping screws and calculation of their slip modulus was carried out. A model of a 22-storey building with a CLT frame was modelled in RFEM. Analyses were run for different values of the slip modulus for comparison of the horizontal displacements connected to each slip modulus. The results show that the deformations were small and that the differences in slip modulus only caused small differences in horizontal deformations even though the variation in slip modulus was wide. The reason for this could be due to the modelling; the model in itself is very stiff, possibly as a result of the façade panels’ vertical adjustment and height. Other factors contributing were the lack of openings for doors and windows in the model, the thickness of the CLT panels as well as the concrete decks on all floors.

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Säll, Harald. "Spiral Grain in Norway Spruce." Doctoral thesis, Växjö universitet, Institutionen för teknik och design, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-538.

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Wood is a major construction material that is used in many contexts, and for different purposes. Serious problems may arise, however, when moisture related deformations as twist occur in wood used in different types of building structures, joinery and furniture. Twist can be explained to a great degree by the helical deviation of the grain angle in relation to the longitudinal direction of the log or the sawn board. Wood fibres form a spiral within the tree, and this is a natural occurrence that is named spiral grain. The wood fibres close to the pith in Norway spruce form a left-handed spiral. In most trees the grain angle turns over to be right-handed with time. Sawn timber that exhibits large grain angles lead to problems of shape stability and stiffness in finished constructions. In this thesis the spiral grain in Norway spruce (Picea abies (L.) Karst.) was stated as well as the effect on sawn timber. The material was based on sample trees from Sweden and Finland. Samples were taken in twenty-two stands at different heights in tree. From six stands studs were sawn and dried for measuring twist and other deformations. The spiral grain was measured with the method scribe test on 390 log discs taken at the top-end of the logs. Account was given concerning changes in grain angle from pith to bark, regarding both increasing annual ring numbers and distance from pith. The development of grain angle over tree age was utilized to study whether annual growth, size of tree, height in tree as well as silvicultural treatments affected spiral grain. Moreover, the relation between grain angle and distance to pith (in mm) was used to forecast twist in sawn timber. The left-handed grain angle was at its greatest between the fourth and eighth annual rings. Thereafter for most trees the grain angle turned from left-handed to right-handed in a linear fashion, in a manner that was unique for each individual tree. The pattern of spiral grain differed significantly between different stands, regarding change of inclination with increasing age or distance from pith. The culmination of the grain angle close to the pith occurred at somewhat higher age higher up in the trunk. The grain angle decreased faster in top logs than it did in the butt logs. The largest trees within a stand had a grain angle that turned to right in a slower way than smaller ones. The thinning strength and type of thinning regime also affected the character of spiral grain in the remaining trees in a stand. There was an indication that strong thinnings, where fast growing trees are retained, may lead to more individuals in a stand that exhibit high grain angles under bark. With knowledge of the size and direction of the grain angle under bark, and the diameter of the log, calculations can be made that show how twisted the sawn timber will be after drying. This can be used for deciding whether an individual log can profitably be sawn and processed further or not. The grain angle under bark can be used to remove trees showing the greatest degree of spiral grain already in the first thinning. Silvicultural methods aiming at even and dense Norway spruce stands, which normally is practised in Scandinavia, will probably result in timber with relatively low risk concerning large grain angle and subsequent risk for twist in sawn wood.

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Kamlot, Wolf-Peter. "Gebirgsmechanische Bewertung der geologischen Barrierefunktion des Hauptanhydrits in einem Salzbergwerk." Doctoral thesis, Freiberg Inst. für Geotechnik, 2009. http://d-nb.info/100371627X/34.

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THOMAS, VINEET SUNNY. "A Multiscale Framework to Analyze Tricuspid Valve Biomechanics." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1542255754172363.

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Kalfeřt, Martin. "Návrh speciálních asfaltových směsí SAL určených pro opravu cementobetonových krytů." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226936.

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In this thesis layer with increased resistance to crack propagation (SAL) are designed. The theoretical part describes the SAL layer, further the input materials, their production and design of various mixtures. The following is a description of the tests, which include tests of permanent deformation, crack propagation, low-temperature characteristics, test, flexural strength and relaxation. After the test results and conclusion are stated.

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Coufalík, Pavel. "Návrh a posouzení směsi pro asfaltové vrstvy se zvýšenou odolností proti šíření trhlin (SAL)." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226447.

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This master's thesis deals with the possibility of special asphalt-rubber mixture using - Stress Absorbing Layer (SAL). In the theoretical part the SAL and test methods are described. In the practical part, several different mixtures are designed and selected mixtures were tested. Low-temperature characteristics, permanent deformations, bending tensile relaxation, stiffness modulus and fatigue properties were determined. Based on the test results the mixtures were compared and their benefit is evaluated according to Performance Pavement Design Method, the pavement structure was evaluated by using of computer programme LayEps.

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Leathers, Michael R. "Balanced structural cross section of the western Salt Range and Potwar Plateau, Pakistan : deformation near the strike-slip terminus of an overthrust sheet /." 1987. http://hdl.handle.net/1957/13150.

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Qayyum, Mazhar. "Crustal shortening and tectonic evolution of the Salt Range in Northwest Himalaya, Pakistan /." 1991. http://hdl.handle.net/1957/9504.

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"Deformation styles of allochthonous salt sheets during differential loading conditions: Insights from discrete element models." Thesis, 2009. http://hdl.handle.net/1911/61823.

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The Discrete Element Method (DEM) was used to model the advance of allochthonous salt sheets through differential loading. The effects of basal slope angle, initial salt thickness, sediment thickness, loading time, progradation rate, and the mechanical strength of the overburden were tested to determine their influence on the development of stratigraphic and structural relationships in the emerging salt and sediment structures. These simulations show that the advance of salt is driven by gravitational instability and sediment loading. Salt advance is greatest with high basal slopes, thick salt, weak sediments, and high sediment progradation rates. The rate of salt advance determines the angle of a subsalt sediment ramp, which influences the final geometry of the system. High angle ramps form with slow salt front advance rates and tend to form counterregional sediment geometries, while low angle ramps form with rapid salt front advance and tend to produce roho geometries.

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Küster, Yvonne. "Bromide characteristics and deformation mechanisms of naturally deformed rock salt of the German Zechstein Basin." Doctoral thesis, 2011. http://hdl.handle.net/11858/00-1735-0000-0006-B304-8.

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Kamlot, Wolf-Peter. "Gebirgsmechanische Bewertung der geologischen Barrierefunktion des Hauptanhydrits in einem Salzbergwerk." Doctoral thesis, 2008. https://tubaf.qucosa.de/id/qucosa%3A22651.

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Im Rahmen von Sicherheitsanalysen kommen Szenarien zur Anwendung, die eine Verletzung der geologischen Barriereintegrität in einem Endlager beschreiben. Während bei der normalen Entwicklung eines Endlagers im Steinsalz von dem langzeitig sicheren Einschluss der radioaktiven Abfälle ausgegangen wird, beschreiben die Szenarien die sogenannte "gestörte" Entwicklung. Das Anhydritszenario hebt auf den Lösungszufluss entlang der Anhydritklüfte und die sich ergebenden Konsequenzen für den Isolationsbereich ab. Obwohl untertägige Untersuchungen gezeigt haben, dass die meisten geologischen Klüfte geschlossen bzw. mit Mineralisationen gefüllt waren, muss in der Störfallanalyse das Anhydritszenario betrachtet werden. Es ist deshalb unverzichtbar, im Rahmen der Integritätsbewertung der geologischen Barriere das gebirgsmechanisch-hydraulische Verhalten des Hauptanhydrits zu bewerten. Die Bedingungen für das Eintreten des Anhydritszenarios müssen untersucht und dafür standortunabhängige Methoden und Kriterien entwickelt werden. In der Arbeit werden die lithologisch-tektonischen Bedingungen untertägiger Hauptanhydritaufschlüsse in unterschiedlichen Salzbergwerken in Thüringen und Sachsen-Anhalt beschrieben und untereinander verglichen. In zwei Gruben in unterschiedlicher Teufe wurden die Spannungsänderungen und Konvergenzen bei der Auffahrung von 2 Messkammern im Hauptanhydrit ermittelt. Vergleichbare Untersuchungen fanden am Grauen Salzton statt, der über Strecken aufgeschlossen war. Unter Verwendung von Bohrkernen fanden umfangreiche Laborversuche zur Festigkeit, Deformierbarkeit und hydraulischen Dichtheit des Anhydrits und Salztons statt. Nach einer umfassenden Analyse der historischen Ereignisse am Staßfurter Sattel vor etwa 100 Jahren wurden die Voraussetzungen für einen Lösungszufluss bewertet und das Szenario nachgerechnet. Es stellte sich heraus, dass die minimale Druckeinspannung eine fundamentale Bedeutung für die hydraulische Integrität besitzt. Für die In-situ-Spannungsmessungen im Anhydrit und benachbarten Steinsalz wurde eine neue Hydrofrac-Messsonde mit seismoakustischer Rissortung gebaut sowie für die Bohrlochschlitzmessungen im Steinsalz eine neuartige Auswertebeziehung unter Berücksichtigung der Tangentialspannungsrelaxation am Bohrlochrand entwickelt. Weiterhin wurde eine einfach anwendbare Methode zur Bestimmung der Permeabilität aus instationären Druckstoßtests eingeführt. In Labortests an Gesteinswürfeln unter drei unterschiedlichen Hauptnormalspannungen konnten Kenntnisse zur Rissbildung und den hydraulischen Eigenschaften gewonnen und Kriterien für die Bewertung der Barrierenintegrität abgeleitet werden. Im Bergwerk Bernburg erfolgten auf dieser Basis In-situ-Tests zur Ermittlung der Rissausbreitung und dem damit verbundenen Fluidfluss unter konstanten Gebirgsspannungen sowie in Abhängigkeit von der Entfernung des Messortes zu einer Abbaufront. Für die abschließenden Schlussfolgerungen und die Festlegung übertragbarer Kriterien wurden ausgewählte Untersuchungen im Labor und in situ unter Verwendung des Fließgesetzes nach Darcy sowie des kubischen Fließgesetzes hydraulisch-mechanisch gekoppelt modelliert.

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Dissertations / Theses on the topic 'Salt deformation'

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