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11	Τεχνικογεωλογικές συνθήκες κατά τη διάνοιξη των σηράγγων Πλατάνου και Τράπεζας της Σ.Γ.Υ.Τ. Κιάτου – Αιγίου. Εφαρμογή αναλυτικών προσεγγίσεων για τον προσδιορισμό της αλληλεπίδρασης αντιστήριξης και περιβάλλουσας βραχομάζας / Geotechnical conditions during the excavation of two tunnels at Platanos and Trapeza of the Kiato - Egio railroad . Application of analytical programs (Plaxis) for determining the interaction between primary support and surrounding rock mass Σωτήρχος, Αλέξανδρος 07 October 2011 (has links) Σκοπός της παρούσας διατριβής είναι η παρουσίαση και μελέτη των τεχνικογεωλογικών συνθηκών κατά την διάνοιξη των σηράγγων Πλάτανου και Τράπεζας της Σ.Γ.Υ.Τ. Κιάτου – Αίγιου. Στην παρούσα εργασία θα γίνει η χρήση αναλυτικών μεθόδων και συγκεκριμένα της μεθόδου ανάλυσης πεπερασμένων στοιχείων του κώδικα Plaxis για τον προσδιορισμό της αλληλεπίδρασης μέτρων αντιστήριξης και περιβάλλουσας βραχομάζας. Αυτό θα γίνει μελετώντας τις μετρημένες κατά την διάνοιξη σύγκλισης και σύγκριση τους με τις υπολογισμένες από την μέθοδο των πεπερασμένων στοιχειών. / In this dissertation are presented and examined the geotechnical conditions during the excavation of two tunnels at Platanos and Trapeza of the Kiato - Egio railroad. Using analytical methods namely finite element method (FEM) and the code Plaxis for determining the interaction between primary support and surrounding rock mass. There examined the real displacement measured during the excavation in contrast with the calculated displacement by FEM. Also, there are correlated vertical displacements at the roof of the tunnel with overburden height. Σήραγγα Πλατάνου Σήραγγα Τράπεζας Κώδικας Plaxis Μέτρα αντιστήριξης 624.151 094 952 7 Plaxis FEM Displacement Overburden height Tunneling Primary support
12	Pore pressure prediction and direct hydrocarbon indicator: insight from the southern pletmos basin, offshore South Africa Lasisi, Ayodele Oluwatoyin January 2014 (has links) >Magister Scientiae - MSc / An accurate prediction of pore pressure is an essential in reducing the risk involved in a well or field life cycle. This has formed an integral part of routine work for exploration, development and exploitation team in the oil and gas industries. Several factors such as sediment compaction, overburden, lithology characteristic, hydrocarbon pressure and capillary entry pressure contribute significantly to the cause of overpressure. Hence, understanding the dynamics associated with the above factors will certainly reduce the risk involved in drilling and production. This study examined three deep water drilled wells GA-W1, GA-N1, and GA-AA1 of lower cretaceous Hauterivian to early Aptian age between 112 to 117.5 (MA) Southern Pletmos sub-basin, Bredasdorp basin offshore South Africa. The study aimed to determine the pore pressure prediction of the reservoir formation of the wells. Eaton’s resistivity and Sonic method are adopted using depth dependent normal compaction trendline (NCT) has been carried out for this study. The variation of the overburden gradient (OBG), the Effective stress, Fracture gradient (FG), Fracture pressure (FP), Pore pressure gradient (PPG) and the predicted pore pressure (PPP) have been studied for the selected wells. The overburden changes slightly as follow: 2.09g/cm3, 2.23g/cm3 and 2.24g/cm3 across the selected intervals depth of wells. The predicted pore pressure calculated for the intervals depth of selected wells GA-W1, GA-N1 and GA-AA1 also varies slightly down the depths as follow: 3,405 psi, 4,110 psi, 5,062 psi respectively. The overpressure zone and normal pressure zone were encountered in well GA-W1, while a normal pressure zone was experienced in both well GA-N1 and GA-AA1. In addition, the direct hydrocarbon indicator (DHI) was carried out by method of post-stack amplitude analysis seismic reflectors surface which was used to determine the hydrocarbon prospect zone of the wells from the seismic section. It majorly indicate the zones of thick hydrocarbon sand from the amplitude extraction grid map horizon reflectors at 13AT1 & 8AT1 and 8AT1 & 1AT1 of the well GA-W1, GA-N1 and GA-AA1 respectively. These are suggested to be the hydrocarbon prospect locations (wet-gas to Oil prone source) on the seismic section with fault trending along the horizons. No bright spot, flat spot and dim spot was observed except for some related pitfalls anomalies Pore pressure Hydrocarbon Direct Hydrocarbon Indicators (DHIs) Seismic Amplitude Reservoirs Disequilibrium Compaction Bright spot Flat spot and Dim spot Overburden Fracture gradient Fracture pressure Bredasdorp basin South Africa
13	Finanční gramotnost jako nástroj pro snížení zadluženosti českých domácností / Financial literacy as a tool for reducing the debt overburden of the Czech households Zítková, Michaela January 2013 (has links) In current time we experience deeper and deeper indebtedness of Czech households and their deterioration into insolvency on one side, on the other side among Czech population was identified a very low rate of financial literacy in the last few years. As a result of these two findings a hypothesis was created that behind the high indebtedness stands the low financial literacy of population and that it is possible to fight indebtedness by increasing financial literacy. The thesis main target is to analyze approach of Czech Republic to financial literacy, particularly as to a tool of prevention of indebtedness of households. Simultaneously its target is to reveal relation between financial literacy and indebtedness. According to these reasons the thesis is based on several theoretical outcomes - the theory of prevention of risky behavior, the theory of financial education as a prevention from hazard and from the theory of implementation as a part of public policy cycle. Examined problem is defined using analysis of indebtedness of Czech households, determines the occasions and results of this risky behavior; and through delimitation issue of financial literacy. Thesis provides a synthesis of knowledge as options and limits of financial literacy in the fight with increasing indebtedness. Empirical part...
14	Evaluation of the Nordland Group overburden as an effective seal for the Sleipner CO2 storage site (offshore Norway) using analytical and stochastic modelling techniques Nicoll, Grant Douglas January 2012 (has links) Saline aquifers and depleted hydrocarbon fields situated beneath the North Sea are currently being proposed as storage repositories for anthropogenic CO2 captured from point source emitters in the UK and mainland Europe. Two experimental sites are already operating successfully offshore Norway: Sleipner since 1996 and Snøhvit since 2007, collectively storing several million tonnes of CO2/year in the sub-surface. Despite the apparent success of these current projects, one of the major public and scientific concerns is the ability of storage sites to retain CO2 on the millennial timescales required for CO2 plume stabilisation and dissolution. Some areas of the North Sea are also known to contain palaeo-gas seepage pathways within overburden sediments that overlie deeper hydrocarbon reservoirs (e.g. Witch Ground Graben). These areas either need to be avoided for CO2 storage or rigorously assessed in terms of leakage risk. Since the Sleipner storage site lies within such a province, this thesis delivers a detailed evaluation of the Nordland Group overburden and a critical assessment of its long-term sealing capability for CO2. From interpretation and detailed mapping of a baseline 3D seismic dataset (acquired before CO2 injection operations commenced in 1996), we have identified numerous palaeo-migration pathways and high-amplitude seismic anomalies within the Nordland Group overburden sediments deposited above the Sleipner CO2 storage site. We attributed these features to thermogenic or biogenic gas migration, accumulation and bio-degradation over geological time. We also mapped a complex network of sand-filled, glacial channels and tunnel valleys distributed within a few hundred metres below seabed and highlighted their significance as potential fluid migration networks and/or secondary storage containment for leaking CO2. Of further significance, we confirmed that these overburden features also create spatial density variations that impact on the accuracy of seismic time-depth conversions, resulting in the probability of topographic distortions being propagated into seismic interpretations and models. To the best of our knowledge no such detailed mapping of the Nordland Group overburden at Sleipner has been undertaken previously. To determine whether the top layer of the CO2 plume at Sleipner might encounter these relict pathways as it ascends and migrates laterally beneath the caprock, we evaluated the critical column heights required for a CO2 accumulation to enter such a pathway under a range of storage conditions for a CH4/CO2/brine system; assuming that these pathways currently contain methane gas. Risking scenarios were based on a range of phase saturation, pressure, temperature, density, viscosity, interfacial tension and wettability conditions likely to be encountered at depths commensurate with the caprock at Sleipner. We concluded that given certain conditions at the caprock, CO2 could leak more easily into palaeo-migration pathways than CH4 (i.e. at lower entry pressures and therefore smaller column heights), assuming that brine densities and, most importantly, pore radii have not changed significantly over geological time (i.e. no cementation or dissolution has taken place). To further understand the dynamic significance of these palaeo-migration pathways, channels and tunnel valleys, including their ability to form inter-connected leakage/migration networks, we constructed a series of high-resolution 3D models of the Sleipner storage site and overburden, then used stochastic basin modelling and simulation techniques to investigate the processes involved during the introduction of CO2 into the storage site over a prolonged time period. Models were populated with geological, stratigraphic and structural information derived from our seismic interpretation. Flow simulations were calibrated to published data and matched to the present-day plume distribution. The absence of observational reservoir pressure and temperature data from Sleipner introduces significant uncertainty to model outcomes with respect to CO2 density and column height estimates and to surmount this difficulty we constrained the caprock temperature to CO2 density estimates obtained from the most recent gravity data observations at Sleipner. We concluded that the overburden heterogeneity is significant and palaeo-migration pathways, highpermeability channels and tunnel valleys at Sleipner may become potential migration pathways for CO2 as the plume continues to spread laterally over the coming decade, but the possible storage response is difficult to quantify given the absence of sufficient overburden rock property information and accurate pressure and temperature data for the storage site. The overall conclusion from this work is that insufficient information was collected within the Sleipner area prior to storage site development and too many significant studies which should have been performed as a pre-requisite (e.g. obtaining a caprock sample for laboratory testing of potential seal capacity), were actually performed some years after CO2 injection operations had already commenced. The pressure and temperature conditions at the caprock depth for the Sleipner storage site are also marginal in terms of maintaining CO2 above critical point conditions in dense phase and thus maximising storage efficiency. Most significantly, no rigorous overburden mapping and risking was performed for Sleipner (such as the work described in this thesis), thus the fact that no leakage has been detected at Sleipner is more due to good fortune than following best practices. Hopefully, our work has highlighted these key deficiencies so that future CO2 storage site feasibility and development studies will be performed more diligently. 553.7
15	Hydro- und geochemische Prozesse in oberflächennahen Kippensedimenten des Braunkohlentagebaus Zwenkau Wiegand, Ute 28 November 2004 (has links) (PDF) Die vorliegende Arbeit wurde im Rahmen des BMBF-geförderten Projektes "Luft- und bodengestützte spektrometrische Untersuchungen zur Differenzierung reaktiv veränderter Braunkohlentagebaugebiete in Mitteldeutschland" (Vorhaben 02 WB 9667/5) als Kooperation zwischen dem GeoForschungsZentrum Potsdam (GFZ), dem Deutschen Zentrum für Luft- und Raumfahrt (DLR), der Gesellschaft für Angewandte Fernerkundung (GAF) und dem Umweltforschungszentrum Leipzig/Halle GmbH (UFZ) angefertigt. Grundidee des Projektes war es, die durch spektrometrische Erfassungsmethoden der Fernerkundung erhaltenen Überfliegungsdaten mittels konventioneller petrographischer, mineralogischer und geochemischer Analytik zu kalibrieren. Der Schwerpunkt dieser Arbeit lag dabei in der Charakterisierung der hydro- und geochemischen Veränderungen in den Kippensedimenten des im mitteldeutschen Raum südlich von Leipzig aufgeschlossenen Braunkohlentagebaus Zwenkau. Zu diesem Zweck wurden die Kippensedimente in Abhängigkeit des Schüttungsalters und der Lagerung untersucht sowie die spezifischen Merkmale der Kippenwässer und Bodengase erfaßt, um die im Kippenkörper ablaufenden chemischen, petrographischen und gefügemäßigen Veränderungen sowie die Wechselwirkungen zwischen den Sedimenten, Wässern und Bodengasen zu beschreiben. Schließlich wird ein Modell zur zeitlichen Entwicklung der Abraumförderbrückenkippe, beginnend bei ihrer Verkippung bis hin zu einem Alter von etwa 20 Jahren, vorgestellt, welches die beobachteten Erscheinungen bezüglich der auftretenden endogenen und exogenen Wechselwirkungsfaktoren gut erklärt. / This thesis was prepared in cooperation with the GeoForschungsZentrum Potsdam (GFZ), the Deutsches Zentrum für Luft- und Raumfahrt (DLR), the Gesellschaft für Angewandte Fernerkundung (GAF), and the Umweltforschungszentrum Leipzig/Halle (UFZ) in frame of the project "Airborne and laboratory spectroscopic studies for differentiation of reactively alterated lignite mining pits in Central Germany" (No. 02 WB 9667/5) which was gratefully supported by the Bundesministerium für Bildung, Wissenschaft, Forschung und Technologie (BMBF). The major idea of the project was to achieve a calibration of the spectroscopic data acquired by the remote sensing though the results obtained from conventionally petrographical, mineralogical and geochemical analyses. The main goal of this thesis was the characterization of the hydro- and geochemical alterations in the conveyor bridge dump of the open lignite mining pit Zwenkau which is located in the Central Germany District southern of Leipzig. Therefore, dependent on their ages in terms of dumping and their surface-near locations the dump sediments were investigated and the specific properties of the different types of dump water and soil gases were acquired as well in order to describe the ongoing chemical, petrographical and structural alterations and interactions between the sediments, the water and the soil gases in the conveyor bridge. Finally, a model of the chronological development of the overburden sediments starting from their spilling up to an age of about 20 years is proposed which well explains the observed phenomena regarding the appearing endogenous and exogenous interaction factors. Geowissenschaften Deutsch: Braunkohlentagebau Abraumförderbrückenkippe Abraumsedimente Kippensedimente Kippenseen Zwenkau Pyritoxidation Sekundärminerale Hydrogeologie Geochemie Englisch: lignite mining pit conveyor bridge dump overburden sediments dump sediments mining lakes Zwenkau pyrite oxidation secondary minerals hydrogeology geochemistry ddc:530
16	Monitorování podzemních staveb s nízkým nadložím / Monitoring of Underground Construction with Low Overburden Lossmann, Jaroslav Unknown Date (has links) Geotechnical monitoring (GTM) is an essential part of the observation method. In the principle it is the measurement and monitoring of preselected magnitudes – their changing values in the course of the constructing process and their partial evaluation. On the measured values basis the correctness of designed structures and technological processes is verified, optionally new technical and organizational measures are adopted in order to guarantee the continuous and safe constructing course. The main goal of the dissertation is to analyze the current state of the problematics and evaluate the methods of GTM in underground structures with low overburden, including suggestions and recommendations for procedures. In the framework of knowledge, practical experience and data analysis, the basic types and procedures of monitoring elements of underground structures with low overburden will be defined.
17	Hydro- und geochemische Prozesse in oberflächennahen Kippensedimenten des Braunkohlentagebaus Zwenkau Wiegand, Ute 29 January 2003 (has links) Die vorliegende Arbeit wurde im Rahmen des BMBF-geförderten Projektes "Luft- und bodengestützte spektrometrische Untersuchungen zur Differenzierung reaktiv veränderter Braunkohlentagebaugebiete in Mitteldeutschland" (Vorhaben 02 WB 9667/5) als Kooperation zwischen dem GeoForschungsZentrum Potsdam (GFZ), dem Deutschen Zentrum für Luft- und Raumfahrt (DLR), der Gesellschaft für Angewandte Fernerkundung (GAF) und dem Umweltforschungszentrum Leipzig/Halle GmbH (UFZ) angefertigt. Grundidee des Projektes war es, die durch spektrometrische Erfassungsmethoden der Fernerkundung erhaltenen Überfliegungsdaten mittels konventioneller petrographischer, mineralogischer und geochemischer Analytik zu kalibrieren. Der Schwerpunkt dieser Arbeit lag dabei in der Charakterisierung der hydro- und geochemischen Veränderungen in den Kippensedimenten des im mitteldeutschen Raum südlich von Leipzig aufgeschlossenen Braunkohlentagebaus Zwenkau. Zu diesem Zweck wurden die Kippensedimente in Abhängigkeit des Schüttungsalters und der Lagerung untersucht sowie die spezifischen Merkmale der Kippenwässer und Bodengase erfaßt, um die im Kippenkörper ablaufenden chemischen, petrographischen und gefügemäßigen Veränderungen sowie die Wechselwirkungen zwischen den Sedimenten, Wässern und Bodengasen zu beschreiben. Schließlich wird ein Modell zur zeitlichen Entwicklung der Abraumförderbrückenkippe, beginnend bei ihrer Verkippung bis hin zu einem Alter von etwa 20 Jahren, vorgestellt, welches die beobachteten Erscheinungen bezüglich der auftretenden endogenen und exogenen Wechselwirkungsfaktoren gut erklärt. / This thesis was prepared in cooperation with the GeoForschungsZentrum Potsdam (GFZ), the Deutsches Zentrum für Luft- und Raumfahrt (DLR), the Gesellschaft für Angewandte Fernerkundung (GAF), and the Umweltforschungszentrum Leipzig/Halle (UFZ) in frame of the project "Airborne and laboratory spectroscopic studies for differentiation of reactively alterated lignite mining pits in Central Germany" (No. 02 WB 9667/5) which was gratefully supported by the Bundesministerium für Bildung, Wissenschaft, Forschung und Technologie (BMBF). The major idea of the project was to achieve a calibration of the spectroscopic data acquired by the remote sensing though the results obtained from conventionally petrographical, mineralogical and geochemical analyses. The main goal of this thesis was the characterization of the hydro- and geochemical alterations in the conveyor bridge dump of the open lignite mining pit Zwenkau which is located in the Central Germany District southern of Leipzig. Therefore, dependent on their ages in terms of dumping and their surface-near locations the dump sediments were investigated and the specific properties of the different types of dump water and soil gases were acquired as well in order to describe the ongoing chemical, petrographical and structural alterations and interactions between the sediments, the water and the soil gases in the conveyor bridge. Finally, a model of the chronological development of the overburden sediments starting from their spilling up to an age of about 20 years is proposed which well explains the observed phenomena regarding the appearing endogenous and exogenous interaction factors. info:eu-repo/classification/ddc/530 ddc:530 Geowissenschaften
18	Prognose und bergschadenkundliche Analyse dynamischer Bodenbewegungen durch oberflächennahen Steinkohlenbergbau in den USA Zimmermann, Karsten 28 March 2011 (has links) (PDF) Der untertägige Abbau von Steinkohle führt zu Bewegungen des überlagernden Gebirges und der Tagesoberfläche. Eine Bewegungsprognose ist im Hinblick auf entstehende Bergschäden weltweit von großer Bedeutung. In dieser Arbeit wird untersucht, ob eine Prognose von Bodenbewegungen im amerikanischen Steinkohlenbergbau mit einem in Europa bewährten Verfahren, einem dynamischen stochastischen Senkungsmodell, möglich ist. Dazu wurde eine Literaturstudie über den bisherigen Kenntnisstand in den USA durchgeführt, abbaubegleitende Bodenbewegungsmessungen aus dem Steinkohlengebiet der Appalachen ausgewertet und durch Modellrechnungen nachgebildet. Es wurde darüber hinaus untersucht, welchen Einfluss die spezifischen Abbaubedingungen und die räumliche und zeitliche Abbauführung auf die Größe und Dynamik von Bodenbewegungen haben. Die theoretischen und praktischen Untersuchungen zeigen einen deutlichen Know-how Vorsprung des europäischen Bergbaus in den Bereichen der Senkungsmodellierung und Bewertung abbauinduzierter Bodenbewegungen und belegen die Anwendbarkeit des Senkungsmodells. Es wurden wichtige Erkenntnisse gewonnen, die Möglichkeiten und Grenzen einer Optimierung des Abbauzuschnitts und der zeitlichen Abbauführung im Sinne einer bergschadensmindernden Abbauplanung aufzeigen. Die Arbeit trägt zur Verbesserung der bergmännischen und markscheiderischen Abbauplanung im Steinkohlenbergbau bei. Bergbau Bergwerk Steinkohlenbergbau Steinkohlenabbau Steinkohlenbergwerk Steinkohle Abbau Streb Strebabbau Bodenbewegung Gebirgsbewegung Deformation Senkung Schieflage Zerrung Pressung Krümmung Bergsenkung Senkungsmodell Senkungsmodellierung Prognose Modellierung Abbauplanung Planung Abbaugeschwindigkeit Bewegungsdynamik Abbaustopp Dynamik Bergschaden Bergschadenkunde Bergschadensminderung Bergschadensmindernde Appalachen USA Pennsylvania Pittsburgh Morgantown Knothe Markscheider Markscheidewesen mining mine coal hard anthracite stone longwall face surface ground movement seam deformation subsidence strata overburden rock mass subsidence slope tilt model modeling prediction planning retreat winning rate speed stop break dynamics impact damage mitigation assessment protection control engineering Appalachia Appalachian basin USA Pennsylvania Pittsburgh Morgantown Knothe Knothe’s method surveyor miner surveying ddc:620 Appalachen USA / Nordoststaaten Steinkohlenbergwerk Steinkohlenbergbau Bergschaden Bergsenkung
19	Prognose und bergschadenkundliche Analyse dynamischer Bodenbewegungen durch oberflächennahen Steinkohlenbergbau in den USA Zimmermann, Karsten 28 March 2011 (has links) Der untertägige Abbau von Steinkohle führt zu Bewegungen des überlagernden Gebirges und der Tagesoberfläche. Eine Bewegungsprognose ist im Hinblick auf entstehende Bergschäden weltweit von großer Bedeutung. In dieser Arbeit wird untersucht, ob eine Prognose von Bodenbewegungen im amerikanischen Steinkohlenbergbau mit einem in Europa bewährten Verfahren, einem dynamischen stochastischen Senkungsmodell, möglich ist. Dazu wurde eine Literaturstudie über den bisherigen Kenntnisstand in den USA durchgeführt, abbaubegleitende Bodenbewegungsmessungen aus dem Steinkohlengebiet der Appalachen ausgewertet und durch Modellrechnungen nachgebildet. Es wurde darüber hinaus untersucht, welchen Einfluss die spezifischen Abbaubedingungen und die räumliche und zeitliche Abbauführung auf die Größe und Dynamik von Bodenbewegungen haben. Die theoretischen und praktischen Untersuchungen zeigen einen deutlichen Know-how Vorsprung des europäischen Bergbaus in den Bereichen der Senkungsmodellierung und Bewertung abbauinduzierter Bodenbewegungen und belegen die Anwendbarkeit des Senkungsmodells. Es wurden wichtige Erkenntnisse gewonnen, die Möglichkeiten und Grenzen einer Optimierung des Abbauzuschnitts und der zeitlichen Abbauführung im Sinne einer bergschadensmindernden Abbauplanung aufzeigen. Die Arbeit trägt zur Verbesserung der bergmännischen und markscheiderischen Abbauplanung im Steinkohlenbergbau bei. info:eu-repo/classification/ddc/620 ddc:620 Appalachen USA / Nordoststaaten Steinkohlenbergwerk Steinkohlenbergbau Bergschaden Bergsenkung

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