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Showing 11 to 20 of 22 (0.058 seconds)Spelling suggestions: "subject:"sandstein"" "subject:"handstein""
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Erschließung sedimentärer Speichergesteine für eine geothermische StromerzeugungLegarth, Björn Alexander. Unknown Date (has links) (PDF)
Techn. Universiẗat, Diss., 2003--Berlin.
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| 12 |
Thermo-mechanical coupled damage behavior of pre-damaged rock sculptures and monuments - laboratory experiments and numerical simulationsLi, Jun 22 September 2017 (has links) (PDF)
Cotttaer sandstone is a quite popular material used for sculptures and monuments for almost 1,000 years. Such sculptures and monuments will be damaged after several years. The reasons for that could be different: mechanical damage due to carving by sculptors, expansion stresses due to salt crystallization or temperature change. Damages also happen sometimes after inappropriate consolidation.
Cottaer sandstone before and after consolidation was investigated by lab testing and numerical simulations in this thesis. The aim is to develop a simulation strategy which can simulate the thermomechanical coupled damage behavior at grain size level. The main research works of this thesis are as follows:
*Uniaxial compression tests, Brazilian tension tests and size effect tests were carried out to investigate the mechanical parameters of original Cottaer sandstone.
*Ultrasonic wave velocity measurement and special biaxial flexural tests were carried out to determine how deep the consolidation material penetrates and how much strength of sandstones is increased by using two different injection materials.
*A Voronoi-based numerical simulation strategy was developed which considers grain size, grain shape and pore size. Mineral components, intra- and inter-granular contacts and intra- and inter-granular fracturing were considered as well.
*Uniaxial compression tests and Brazilian tension tests of unconsolidated sandstone were simulated. This simulation strategy can capture inter- and intra-granular fracturing.
*Prediction of thermo-mechanical coupled behavior of consolidated and unconsolidated sandstone samples was performed. The simulation results show that thermal properties of grains and filled pores have influence on temperature distribution and fracture development in the sandstone. Also, thermal induced displacements are strongly influenced by boundary condition.
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| 13 |
Die Genese des Grödner Sandsteines der nordwestlichen Dolomiten Südtirol, Italien /Koch, Johannes, January 1982 (has links)
Thesis (doctoral)--Universität zu Köln, 1982. / Includes bibliographical references (p. 139-151).
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| 14 |
Die sedimentologische Entwicklung der Permabfolge im westlichen Südtirol (N-Italien)Fels, Helmut, January 1900 (has links)
Thesis (doctoral)--Universität zu Köln, 1982. / Bibliography: p. 131-144.
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| 15 |
Thermo-mechanical coupled damage behavior of pre-damaged rock sculptures and monuments - laboratory experiments and numerical simulations: Thermo-mechanical coupled damage behavior of pre-damaged rock sculptures and monuments - laboratory experiments and numerical simulationsLi, Jun 13 September 2017 (has links)
Cotttaer sandstone is a quite popular material used for sculptures and monuments for almost 1,000 years. Such sculptures and monuments will be damaged after several years. The reasons for that could be different: mechanical damage due to carving by sculptors, expansion stresses due to salt crystallization or temperature change. Damages also happen sometimes after inappropriate consolidation.
Cottaer sandstone before and after consolidation was investigated by lab testing and numerical simulations in this thesis. The aim is to develop a simulation strategy which can simulate the thermomechanical coupled damage behavior at grain size level. The main research works of this thesis are as follows:
*Uniaxial compression tests, Brazilian tension tests and size effect tests were carried out to investigate the mechanical parameters of original Cottaer sandstone.
*Ultrasonic wave velocity measurement and special biaxial flexural tests were carried out to determine how deep the consolidation material penetrates and how much strength of sandstones is increased by using two different injection materials.
*A Voronoi-based numerical simulation strategy was developed which considers grain size, grain shape and pore size. Mineral components, intra- and inter-granular contacts and intra- and inter-granular fracturing were considered as well.
*Uniaxial compression tests and Brazilian tension tests of unconsolidated sandstone were simulated. This simulation strategy can capture inter- and intra-granular fracturing.
*Prediction of thermo-mechanical coupled behavior of consolidated and unconsolidated sandstone samples was performed. The simulation results show that thermal properties of grains and filled pores have influence on temperature distribution and fracture development in the sandstone. Also, thermal induced displacements are strongly influenced by boundary condition.
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Improving Oil Recovery (IOR) with Polymer Flooding in a Heavy-Oil River-Channel Sandstone ReservoirLu, Hongjiang 13 July 2009 (has links) (PDF)
Most of the old oil fields in China have reached high water cut stage, in order to meet the booming energy demanding, oil production rate must be kept in the near future with corresponding IOR (Improving Oil Recovery) methods. Z106 oilfield lies in Shengli Oilfields Area at the Yellow River delta. It was put into development in 1988. Since the oil belongs to heavy oil, the oil-water mobility ratio is so unfavourable that water cut increases very quickly. Especially for reservoir Ng21, the sand rock is sediment from river channel, the permeability heterogeneity and heavy oil properties together lead to extremely poor water flooding efficiency. In order to improve the oil recovery, IOR methods are needed urgently. Considering all practical situations for this reservoir and present technique level, polymer flooding method has been selected as an IOR test with numerical simulation. For polymer flooding, since polymer resolution has the capability of enlarging water viscosity, it controls the mobility of water phase and at the same time improves the driving efficiency. During polymer flooding simulation, many factors must be taken into account for the construction of mathematical model, such as inaccessible pore volume, polymer shear thinning effect, polymer adsorption, relative permeability reduction factors, etc. All simulations were done with black oil model with polymer option in ECLIPSE. Simulation results for a theoretical river channel reservoir with serious permeability heterogeneity and heavy oil, and simulation results for practical reservoir Ng21, both have shown that polymer flooding is a feasible method for IOR. For reservoir Ng21, with polymer slug size of 0.235 PV, polymer concentration at 1.5 kg/m3, the final oil recovery after polymer flooding could reach 12.8%, the enhanced oil recovery is about 5%. If only the developable oil reserve being taken into account, the final oil recovery is about 34%, and enhanced oil recovery from polymer flooding is more than 12%. For such heavy oil river channel reservoir to reach such a final oil recovery, it could be concluded as a great success. Since there are still many such oil reservoirs in Shengli Oilfields Area, polymer flooding will be of great importance for improving oil recovery in this area in the near future.
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| 17 |
Improving Oil Recovery (IOR) with Polymer Flooding in a Heavy-Oil River-Channel Sandstone ReservoirLu, Hongjiang 06 April 2004 (has links)
Most of the old oil fields in China have reached high water cut stage, in order to meet the booming energy demanding, oil production rate must be kept in the near future with corresponding IOR (Improving Oil Recovery) methods. Z106 oilfield lies in Shengli Oilfields Area at the Yellow River delta. It was put into development in 1988. Since the oil belongs to heavy oil, the oil-water mobility ratio is so unfavourable that water cut increases very quickly. Especially for reservoir Ng21, the sand rock is sediment from river channel, the permeability heterogeneity and heavy oil properties together lead to extremely poor water flooding efficiency. In order to improve the oil recovery, IOR methods are needed urgently. Considering all practical situations for this reservoir and present technique level, polymer flooding method has been selected as an IOR test with numerical simulation. For polymer flooding, since polymer resolution has the capability of enlarging water viscosity, it controls the mobility of water phase and at the same time improves the driving efficiency. During polymer flooding simulation, many factors must be taken into account for the construction of mathematical model, such as inaccessible pore volume, polymer shear thinning effect, polymer adsorption, relative permeability reduction factors, etc. All simulations were done with black oil model with polymer option in ECLIPSE. Simulation results for a theoretical river channel reservoir with serious permeability heterogeneity and heavy oil, and simulation results for practical reservoir Ng21, both have shown that polymer flooding is a feasible method for IOR. For reservoir Ng21, with polymer slug size of 0.235 PV, polymer concentration at 1.5 kg/m3, the final oil recovery after polymer flooding could reach 12.8%, the enhanced oil recovery is about 5%. If only the developable oil reserve being taken into account, the final oil recovery is about 34%, and enhanced oil recovery from polymer flooding is more than 12%. For such heavy oil river channel reservoir to reach such a final oil recovery, it could be concluded as a great success. Since there are still many such oil reservoirs in Shengli Oilfields Area, polymer flooding will be of great importance for improving oil recovery in this area in the near future.
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| 18 |
Steckbrief Podsol aus Sandstein: Böden der Berg- und HügelländerPickert, Enrico, Bräutigam, Tatjana 07 May 2021 (has links)
Der Steckbrief informiert über den ˈPodsol aus Sandsteinˈ. Der ˈPodsol aus Sandsteinˈ zählt zur Bodenklasse der ˈBöden der Berg- und Hügelländerˈ. Er stellt eine typische Bodenform in Sachsen dar. Er ist ein nährstoffarmer Boden, der sich typisch in der ˈBodenregion der Berg- und Hügelländer mit hohem Anteil an nichtmetamorphen Sand-, Schluff-, Ton- und Mergelsteinenˈ entwickelt hat. Podsole sind nährstoffarme Böden, die sich durch Verlagerungsprozesse und teilweise Wiederausfällung von Fe, Al, und weiteren Elementen zusammen mit organischen Stoffen auszeichnen und dadurch im oberen Profilteil extrem verarmt sind. Der Steckbrief richtet sich an alle Interessierte, die sich über die Entstehung Verbreitung und das Erscheinungsbild typischer, repräsentativer Böden Sachsens informieren möchten.
Redaktionsschluss: 01.03.2017
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| 19 |
Stratigraphie, Fazies und geothermisches Potenzial von fluvio-deltaischen Ablagerungsräumen der Oberen Trias und des Unteren Jura im östlichen Teil des Mitteleuropäischen BeckensBarth, Gregor 09 December 2019 (has links)
Die vorliegende, aus insgesamt vier Einzelveröfffentlichungen bestehende Dissertation soll den Kenntnisstand über fazielle und biostratigraphische Entwicklungen und Gliederungsmöglichkeiten in der höheren Trias und dem Unteren Jura im östlichen Teil des Mitteleuropäischen Beckens (insbesondere des Norddeutschen Beckens) erweitern, und die bislang verfügbaren Daten in einem Kontext wiedergeben. Als wesentliche Punkte der Arbeit sollen genannt werden:
1. Verbesserung des stratigraphischen Gerüsts: Basierend auf hochauflösender Palynostratigraphie (in der Exter-Formation, Rhätkeuper) und der biostratigraphisch kontrollierten Definition von sequenzstratigraphischen Flutungs- und Regressionsflächen (im Unteren Jura) konnten konkrete Zeitscheiben ausgewiesen werden, auf deren Grundlage Untergrund-Fazieskarten erstellt worden sind. Durch Korrelation gleichalter Ablagerungen kann u. a. der Trias-Jura-Übergang im Norddeutschen Becken besser identifiziert werden.
2. Sedimentologische und biofazielle Untersuchungen an gekernten Bohrungen und Übertageaufschlüssen ermöglichen die Rekonstruktion von hochauflösenden Untergrund-Fazieskarten innerhalb der konkretisierten Zeitscheiben, die Ablagerungsmodelle und biofazielle Zonierungen (Rhätkeuper bis Toarc) wiedergeben. Diese Ergebnisse können mittels Korrelation geophysikalischer Bohrlochmessungen auf Profile übertragen werden, von denen keine Festgesteinsprobe (mehr) vorliegt. Zusätzlich wird ein Vergleich mit rezenten Ablagerungssystemen möglich.
3. Bezugnahme der Ergebnisse auf die angewandte Forschung, insbesondere die Erkundung des geologischen Untergrundes und die Abschätzung der Reservoirqualität (mithilfe von geohydraulischen Messwerten [Porosität, Permeabilität] sowie hochauflösender Reservoirqualitätskarten, die aus den Untergrund-Fazieskarten abgeleitet worden sind). In Vorbereitung geothermischer Projekte ermöglichen diese Karten eine verbesserte standortbezogene Reservoirprognose, als dies bisher im östlichen Norddeutschen Becken möglich ist.
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| 20 |
Late Mesozoic to Cenozoic erosion and sediment dispersal in the Dinaride orogen: a sedimentary provenance approach / Spätmesozoische bis Känozoische Erosion und Sedimentschüttung im Dinarischen Orogen: Ansätze aus der ProvenanzanalyseMikes, Tamás 16 December 2008 (has links)
No description available.
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