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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Geoarchaeological Investigations Around Kultepe (kayseri)

Omeroglu, Isil 01 September 2011 (has links) (PDF)
The purpose of this study is to investigate the effect of geology on ancient K&uuml / ltepe settlement located in a tectonically active area, namely Sarimsakli basin, shaped by Central Anatolian Fault Zone. Four main data sources used in this study are geological map, digital elevation model (DEM), slip plane and the borehole data. Geological maps are used for the determination of key horizons and the faults shaping the basin. Slip data measured in the field are used to identify the nature of the faults. Borehole data are used for the preparation of Quaternary thickness map and the borehole-to-borehole sections across the basin. Morphology of the area is investigated using the DEM with a particular emphasis on the drainage characteristics of the basin. The analyses have shown that the faults shaping the basin are still active suggesting vertical movements today as well as during the historical period. According to morphological analysis, the basin is drained by a single channel (Karasu river) which is controlled by the western segment of the fault zone. If the fault activates, the channel is elevated resulting in the formation of a lake behind the channel. Accordingly, the present morphological configuration suggests that a water level elevated for 70 m will totally bury K&uuml / ltepe.
62

Design of an underground compressed hydrogen gas storage

Powell, Tobin Micah 14 February 2011 (has links)
Hydrogen has received significant attention throughout the past decade as the United States focuses on diversifying its energy portfolio to include sources of energy beyond fossil fuels. In a hydrogen economy, the most common use for hydrogen is in fuel cell vehicles. Advancements in on-board storage devices, investment in hydrogen production facilities nation-wide, development of a hydrogen transmission infrastructure, and construction of hydrogen fueling stations are essential to a hydrogen economy. This research proposes a novel underground storage technique to be implemented at a hydrogen fueling station. Three boreholes are drilled into the subsurface, with each borehole consisting of an outer pipe and an inner pipe. Hydrogen gas (H2) is stored in the inner tube, while the outer pipe serves to protect the inner pipe and contain any leaked gas. Three boreholes of varying pressures are necessary to maintain adequate inventory and sufficient pressure while filling vehicles to full tank capacity. The estimated cost for this storage system is $2.58 million. This dollar amount includes drilling and completion costs, steel pipe costs, the cost of a heavy-duty hydrogen compressor, and miscellaneous equipment expenses. Although the proposed design makes use of decades’ worth of experience and technical expertise from the oil and gas industry, there are several challenges—technical, economic, and social—to implementing this storage system. The impact of hydrogen embrittlement and the lack of a hydrogen transmission infrastructure represent the main technical impediments. Borehole H2 storage, as part of a larger hydrogen economy, reveals significant expenses beyond those calculated in the amount above. Costs related to delivering H2 to the filling station, electricity, miscellaneous equipment, and maintenance associated with hydrogen systems must also be considered. Public demand for hydrogen is low for several reasons, and significant misperceptions exist concerning the safety of hydrogen storage. Although the overall life-cycle emissions assessment of hydrogen fuel reveals mediocre results, a hydrogen economy impacts air quality less than current fossil-fuel systems. If and when the U.S. transitions to a hydrogen economy, the borehole storage system described herein is a feasible solution for on-site compressed H2 storage. / text
63

Application of fluid electrical conductivity logging for fractured rock aquifer characterisation at the University of the Western Cape's Franschhoek and Rawsonville research sites

Lasher, Candice January 2011 (has links)
<p>&nbsp / Characterisation of fractured rock aquifers is important when dealing with groundwater protection and management. Fractures are often good conduits for water and contaminants, leading to high flow velocities and the fast spread of contaminants in these aquifers. A cost effective methodology is required for the characterisation of the role of individual fractures contributing to flow to boreholes in fractured rock aquifers. Literature shows that some of the conventional methods used to characterise hydraulic properties in fractured rock aquifers are expensive, complicated, time consuming and are associated with some disadvantages such as over-or under- estimations of flow rates. iii This thesis evaluates the use of Fluid Electrical Conductivity (FEC) logging in fractured rock aquifers. This FEC data are compared to various traditional methods used to determine aquifer hydraulic properties applied at the Franschhoek and Rawsonville research sites. Both these sites were drilled into the fractured rock Table Mountain Group (TMG) Aquifer, forming one of the major aquifers in South Africa.</p>
64

Geological and anthropogenic impacts on inorganic water quality at rural clinics in the Limpopo Province, South Africa / van Heerden, K.

Van Heerden, Karien January 2011 (has links)
This study gives insight to the origin of pollution in the water resources of the Limpopo province of South Africa. The Limpopo province is the largest rural province in South Africa. Up to 40% of the total population does not have access to sufficient water supply, resulting in adverse health effects. The purpose of this study is to determine (1) the degree of inorganic pollution of borehole water; (2) to identify the pollution sources, and (3) to determine whether the pollution is inherited from the surface water that recharges the groundwater or is caused on site near the bore holes. In order to achieve these objectives, surface water quality data (14 675 samples) and borehole water data (340 samples) at health facilities were analysed. A pollution index, defined by the following ratio: Pollution index (%) = 100 x ([Cl–] + 2[SO4^-2] + [NO3-] + 3[PO4^-3]) ÷ ([Cl-] + 2SO4^-2 + [NO3-] + [PO4^-3] + [HCO3-]) was used to determine the percentage of contribution of each chemical species towards pollution. This ratio is based on the fact that bicarbonate is released during chemical weathering of rocks whereas sulphate, nitrate, chloride, and phosphate are anthropogenic in origin. The pollution index shows that 6% of the surface waters and 21% of the borehole water is severely polluted. The pollution of the surface water is characterized by high concentrations of sulphate whereas the pollution of the borehole water is characterized by high concentrations of chloride. This indicates that the pollution of the borehole water is not so much the result of the infiltration of polluted surface water, but rather the result of on–site pollution on the surface near the bore holes. / Thesis (M.Sc. (Geography and Environmental Studies))--North-West University, Potchefstroom Campus, 2011.
65

Geological and anthropogenic impacts on inorganic water quality at rural clinics in the Limpopo Province, South Africa / van Heerden, K.

Van Heerden, Karien January 2011 (has links)
This study gives insight to the origin of pollution in the water resources of the Limpopo province of South Africa. The Limpopo province is the largest rural province in South Africa. Up to 40% of the total population does not have access to sufficient water supply, resulting in adverse health effects. The purpose of this study is to determine (1) the degree of inorganic pollution of borehole water; (2) to identify the pollution sources, and (3) to determine whether the pollution is inherited from the surface water that recharges the groundwater or is caused on site near the bore holes. In order to achieve these objectives, surface water quality data (14 675 samples) and borehole water data (340 samples) at health facilities were analysed. A pollution index, defined by the following ratio: Pollution index (%) = 100 x ([Cl–] + 2[SO4^-2] + [NO3-] + 3[PO4^-3]) ÷ ([Cl-] + 2SO4^-2 + [NO3-] + [PO4^-3] + [HCO3-]) was used to determine the percentage of contribution of each chemical species towards pollution. This ratio is based on the fact that bicarbonate is released during chemical weathering of rocks whereas sulphate, nitrate, chloride, and phosphate are anthropogenic in origin. The pollution index shows that 6% of the surface waters and 21% of the borehole water is severely polluted. The pollution of the surface water is characterized by high concentrations of sulphate whereas the pollution of the borehole water is characterized by high concentrations of chloride. This indicates that the pollution of the borehole water is not so much the result of the infiltration of polluted surface water, but rather the result of on–site pollution on the surface near the bore holes. / Thesis (M.Sc. (Geography and Environmental Studies))--North-West University, Potchefstroom Campus, 2011.
66

Determination of in situ V[subscript s] and G[subscript max] using surface wave measurements in cased and uncased boreholes /

Kalinski, Michael E. January 1998 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 401-406). Available also in a digital version from Dissertation Abstracts.
67

Downhole Physical Property Logging of the Blötberget Iron Deposit, Bergslagen, Sweden / Geofysisk borrhålsloggning i apatitjärnmalmer, norra Bergslagen

Johansson, Philip January 2017 (has links)
Geophysical methods are frequently applied in conjunction with exploration efforts to increase the understanding of the surveyed area. Their purpose is to determine the nature of the geophysical response of the subsurface, which can reveal the lithological and structural character. By combining geophysical measurements with the drill core data, greater clarity can be achieved about the structures and lithology of the borehole. The purpose of the project was to give the student an opportunity to discover borehole logging operations and to have a greater understanding of the local geology, in particular the iron mineralizations in the apatite iron ore intersected by the boreholes. In order to do this, the student participated in performing a geophysical borehole survey and analyzing the results. These were combined with a drill core log in order to cross plot the results and increase understanding. / Geofysiska metoder används ofta i samband med prospektering för att öka förståelsen av området. Utförda från ytan ger de en relativt god tolkning av vad som kan finnas på djupet och är även kostnadseffektiva jämfört med provborrning. Borrhålsloggning sker däremot efter att själva hålet borrats och ändamålet är ofta att utöka förståelsen om området omedelbart kring det loggade hålet. Genom att kombinera geofysisk fältdata med tolkning av borrkärnan kan man erhålla en ökad förståelse för borrhålets strukturer och litologi. Syftet med det här projektet var att utöka studentens förståelse inom borrhålsloggning, samt att avgöra hur relevant metoden är för att identifiera järnmineraliseringar i apatitjärnmalmen som kännetecknar norra Bergslagen
68

Assessment of rock mass quality and its effects on charge ability using drill monitoring technique

Ghosh, Rajib January 2017 (has links)
No description available.
69

Hydrogeological characterisation of crystalline basement aquifers within the Limpopo Province, South Africa

Holland, Martin 21 June 2011 (has links)
Geologically complex crystalline aquifers are distributed extensively in Africa and also underlie large parts of the semi-arid Limpopo Province where some of the greatest groundwater needs in South Africa occur. The importance of these basement aquifers makes it vital to identify high yielding hydrogeological zones that can be targeted for water supply, to sustain areas of high population density with few or no alternative water sources. The biggest challenge is to understand the factors that determine the secondary permeability of these weathered-fractured rock aquifers. The focus of this study was therefore to systematically analyse regional factors that may influence borehole yields and aquifer transmissivities. The study covered four distinct geological and morpho-structural domains within the Limpopo Province, covering about 23 500 km2. The borehole dataset compiled for the study consisted of over 8 000 boreholes contained in the Groundwater Resources Information Project (GRIP) Limpopo database of the South African Department of Water Affairs. Approximately 3 000 of these boreholes have been hydraulically tested and the lithology has been recorded in 1 200 cases. A commonly encountered problem of pumping tests analysis in crystalline aquifers is in choosing an appropriate model that best fits the observed drawdown response. In this thesis modern methods are proposed for the analysis of pumping test data in weathered-fractured rock aquifers and highlight the importance of diagnostic plots, especially derivatives, for the detection of flow regimes and the choice of the correct ‘theoretical’ model. Based on the classification no single analytical method can be universally applied to crystalline basement aquifers when considering the analysis of pumping test data. The GRIP borehole dataset was analysed in conjunction with spatial information to identify the relationship of regional factors such as - geology, hydrology, weathering thickness, topography, geomorphology, neo-tectonic stresses, and structural lineaments - on groundwater occurrence. Geology has a clear influence, with boreholes exploiting alluvial aquifers composed of highly permeable material, and certain rock types such as pegmatite, showing generally higher borehole productivities. Favourable borehole locations from a topographical point of view are predictably along rivers and valleys. Other identified favourable groundwater targets are the metamorphic aureoles of younger granite intrusions. Despite the local importance of the regolith as a recharge and storage mechanism for the underlying fractured bedrock, no correlation between borehole yields and depth of weathering was found. The pattern of lineament and dyke orientations in the different morpho-structural domains led to a more complex conceptual model of groundwater occurrence. This model is inconsistent with the predicted regime based on regional stress field data and suggests that local variations have a strong influence on groundwater occurrence. Due to the complex geological history of the area, it is difficult to link open discontinuities to a distinct recent or past tectonic event. It can be concluded that regional stress field data, as in this case, may not account for local, possibly highly significant, stress field variations. The hydrogeological importance of several factors on groundwater occurrence presented in this study can be used as a working reference for future groundwater development programmes. / Thesis (PhD)--University of Pretoria, 2011. / Geology / unrestricted
70

Practical evaluation of borehole heat exchanger models in TRNSYS

Thorén, Åsa January 2016 (has links)
Vertical ground source heat pumps are established and still growing on the global market. The modelling of these systems is important for system design and optimization. This is an active field of research, and many models are often built into system simulation software such as TRNSYS. With the intention of having a better sensibility for existing TRNSYS tools, three different cases are simulated with several TRNSYS tools, so called Types. A Thermal Response Test, a large borehole field of an IKEA building complex in Sweden, as well as the Marine Corps Logistic Base in Albany, USA. The vertical ground heat exchanger types 203, 244, 243, 246, 451, 55a and 557b are used. Most of the simulations are investigated and evaluated by comparing them to measured data. The result shows that, for these specific cases, the DTS types 557a and 557b can underestimate the heat transfer early on due to a poor consideration of the thermal capacity inside the borehole. Depending on how the thermal resistance is calculated by a module, the fluid mean temperature simulation is affected by a constant throughout the simulation time. The simulation results indicate that the type 557b, where the borehole resistance is pre-set as an input and known from experimental data, is the most accurate of the types for groundwater filled boreholes. On short term, type 451 provides a good coherence with the measured data, with a relative deviation of 10.3 %. The borehole models that consider the borehole thermal capacity overestimate the short term heat transfer rate, whereas those that neglect the borehole capacity underestimate the short term thermal heat transfer on short term. Existing Types describe successfully the long term behaviour of large borehole fields. Serial versus parallel coupled BHE fields show relatively small differences in performance when simulated with type 557b for a specific study case.

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