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Le bassin versant du Bandama blanc amont, au nord de la Côte d’Ivoire, est situé sur un socle fissuré, composé de granites et de schistes, et constitue un aquifère pérenne pour l’approvisionnement en eau des populations. Cet aquifère de type fissuré est mal connu, tant dans la géométrie des réservoirs que dans le potentiel hydrogéologique des réserves qu’il contient. La précarité des populations rurales est en partie liée au manque d’eau potable ainsi qu’au nombre encore insuffisant des points d’approvisionnement. Un nombre important d’échecs a été observé lors de la réalisation des ouvrages de captages des eaux souterraines, dont l'une des causes est une faible connaissance du fonctionnement du milieu. Cette étude consiste à améliorer les connaissances sur le fonctionnement hydrodynamique des réservoirs du socle fissuré (géométrie des aquifères, paramètres hydrodynamiques, recharge, disponibilité de la ressource) en vue de l’installation d’ouvrages de captage.L’approche méthodologique multidisciplinaire intègre des méthodes d’hydrogéophysique, d’hydrogéologie, de géologie et de chimie. Il s’agit de développer de nouvelles techniques et outils appropriés de prospection pour affiner la caractérisation du socle fissuré, afin de mieux contraindre l'exploitation des sites, notamment en termes de stabilité des débits prélevés.Pour étudier l’aquifère de socle du bassin versant du Bandana blanc amont, nous avons couplé des mesures électromagnétiques aux données lithologiques pour affiner la géométrie de l'aquifère et de mieux contraindre le choix pour les futurs localisations des forages. Cette étude présente donc une nouvelle approche hydrogéophysique pour améliorer la connaissance des ressources importantes dans un aquifère de socle, à l’échelle locale ou régionale, par l'utilisation du système électromagnétique multifréquentiel PROMIS. L'interprétation des résultats a conduit à proposer des modèles multicouches conformes à la structuration lithologique et discontinuités géologiques en place, et à la localisation de l'aquifère, sa géométrie et les interfaces de sa base et du toit.Cette méthode est efficace pour améliorer la caractérisation de l’aquifère de socle, et les résultats ont révélé une bonne concordance entre les sondages (1D), la section de résistivité (2D), les forages et les structures géologiques.La géométrie de l’aquifère présente une structure multicouche présentant de haut en bas de la cuirasse ferrugineuse, des arènes argileuses, une zone fissurée reposant sur un substratum rocheux. Nous sommes en présence d’une nappe captive, sous pression sous les argiles, contenue dans les arènes et la frange fissurée, et présentant une épaisseur variable entre 15 et 30 m. Une connaissance détaillée de la géométrie de l'aquifère locale constitue la première étape cruciale avant d'aller plus loin dans une étude hydrogéologique complète. / The upstream watershed of White Bandama, north of Ivory Coast, is located on a fissured hard-rock, composed of granites and schists, and is a perennial aquifer for populations’ water supply. The upstream watershed of White Bandama, northern Ivory Coast, is located on a hard-rock aquifer which geometry and potential as an hydrogeological reserve is not yet well characterized. Insecurity of rural populations is partly due to lack of drinking water as well as still inadequate number of water supply points. A significant number of failures was observed when performing wells and boreholes for groundwater, one of the causes is a weak scientific knowledge on the environment.This study is to improve knowledge on the hydrodynamic behavior of the hard rock reservoir (geometry of aquifers, hydrodynamic parameters, recharge, availability of the resource) in order to drill perennial boreholes.The multidisciplinary methodological approach integrates hydrogeophysics, hydrogeology, geology, chemistry methods. It is to develop new techniques and appropriate exploration tools to refine the characterization of fissured hard-rock to better constrain the operation of sites, especially in terms of stability of pomped yield.To study the hard-rock aquifer of upstream watershed of White Bandama, we coupled electromagnetic measurements to lithological data to refine the geometry of the aquifer and to better constrain the choice for future drilling locations. This study presents a new hydrogeophysical approach using the multifrequency electromagnetic device PROMIS® to improve knowledge of resources on hard-rock aquifer, at the local or regional level.Our geophysical data are interpreted with multi-layer models consistent with the discontinuities observed in lithology logs and the geology of the site. This method is effecient to improve the characterization of the hard-rock aquifer, and the results showed good agreement between the soundings (1D), the resistivity cross-section (2D), drillings and geological structures.Results allow to precise the local thicknesses of the 3 main units of our study area down to 50 m, being from top to down, saprolite, a fissured-rock zone and the rock substratum. The fissured-rock zone constitutes the main aquifer unit under pressure, interesting target for productive water wells. Its thickness ranges from 15 to 30 m. A detailed knowledge of the local aquifer geometry constitutes the first and crucial step before going further into a complete hydrogeological study.

Stockholm archipelago is a combination of coastal and young glaciated conditions on hard rock geology with almost no primary porosity and very limited secondary porosity. Therefore the aquifer is both of limited capacity and exposed to salinity problem. In this context importance of fractures and soil cover is magnified. Lineaments are representatives of fractures in remote sensing. Fracture mapping in study area proves close correspondence between orientation of fractures and nearly located lineaments. Especially in this type of terrain, lineaments normally occur together with many other interesting hydrogeological features such as topographic attributes, soil, and vegetation; however, still each of these factors has its own effect on the groundwater situation. Through employment of geostatistical analysis and a modified variant of the RV (Risk Variable) method, called the PV (Probability Value) method, different attributes are rated by importance. The results show, soil cover is the most influencing factor then rock type and distance from lineaments; other factors are classified after them. It is discovered that the center of lineaments may not be the most suitable site to extract water because of being clogged by fills. This is particularly the case for shear fractures in which clay can be internally formed due to friction. Based on the statistical results a model is made in GIS environment in order to create hydrogeological maps. Such maps, after validation, can be used for any other area with similar properties even with missing or very limited data from boreholes. These maps definitively are only probability maps projecting areas with higher and lower prospect of aquifer potential and cannot guarantee high capacity in every borehole drilled in designated areas due to high heterogeneity of fractured rock system. Analysis of chemical data from wells proves a correlation between fracture orientations and topography with salinization and groundwater flow. Groundwater flow in the surroundings seems to be essential for feeding the aquifer as most of the wells with increased salt content have also low capacities.

The research study, Caught between Christianity and the hard rock: A narrative study, presents, explores and discusses the stories of Christian hard rock musicians from a predetermined Christian hard rock band, comprising of four members. The study takes a narrative approach at exploring and discussing the participants’ stories, which comprise the qualitative data for the study. The stories were collected by means of four individual semi-structured interviews and a group unstructured interview. The interviews sought to ask the participants certain questions to hear and collect their stories pertaining to the various narratives interplaying in their lives as Christian hard rock musicians. Following collection and transcription of these stories, the stories were analysed according to interpretive narrative analysis, according to Riessman, with reference to Labov’s 6 elements of transcription. Such stories were subsequently reported and discussed within the research study from a narrative theoretical point of departure. This allows for the reader to gain an understanding of the various narratives interplaying in the lives of Christian hard rock musicians, and the significance of such narratives and their experiences, which ultimately is assumed to influence the participants’ daily lives. Ultimately, the study facilitates for the participants to tell their stories as they wished to tell them, in terms of how they may be “caught between Christianity and the hard rock” music genre. Subsequently the study also serves for the reader to gain a narrative understanding as to how the band members understand themselves and their band to be in the world. / Dissertation (MA)--University of Pretoria, 2013. / gm2014 / Psychology / unrestricted

Musik finns i alla kulturer och berör oss alla på olika sätt. Syftet med denna uppsats är att söka en djupare förståelse för vad en musikgenre kan betyda för elever. Studien går ut på att undersöka hur elever använder musiken för att klara av sin vardag både vad gäller skola och fritid. Det har i utredningar visats att musik är viktig för inlärning av kärnämnen. I mitt arbete som musiklärare har jag fått höra från elever att de inte skulle komma till skolan om det inte var för musikämnena. Det är musiken som gör skolan intressant och som gör att de orkar delta även i andra ämnen. Läraren är viktig för elevernas utbildning. En modern lärare använder sig av relationellt lärande. Metoden går ut på att läraren skapar en relation där eleven ges förtroende och stort utrymme i undervisningen. I relationen måste läraren släppa på sin auktoritet och en kamp kan då uppstå mellan lärare och elev, vilket kräver både kunskap och mod av läraren. / Music exists in all cultures and affects us all in different ways. The purpose of this study is to seek a deeper understanding of what a genre of music can mean to students. The study is to investigate how students use music to cope with their daily lives both in school and leisure. Investigations have shown that music is important to the learning of main subjects. In my job as a music teacher I have learnt from students that they would not come to school if it was not for the music subjects. It's the music that makes the school attractive and enables them to have the energy to participate in other subjects. The teacher is important for the students' education. A modern teacher uses ”relational learning”. The approach is that the teacher creates a relationship where students are given freedom and space in class. In the relationship with the student the teacher must let go of his authority and a struggle can then occur between teacher and student, which requires both the knowledge and the courage of the teacher.

The study of deformation zones is of great geological interest since these zones can separate rocks with different characteristics. The geometry of these structures with depth is important for interpreting the geological history of an area. Paper I to III present 2D reflection seismic data over deformation zones targeting structures in the upper 3-4 km of the crust. These seismic profiles were acquired with a crooked-line recording geometry. 2D seismic processing assumes a straight recording geometry. Most seismic processing tools were developed for sub-horizontally layered structures. However, in the crystalline rocks in Scandinavia more complex structures with contrasting dip directions and folding are common. The crooked-line recording geometries have the benefit of sampling a 3D volume. This broader sampling can be used to gain knowledge about the true geometry of subsurface structures. Correlation with geological maps and other geophysical data along with seismic data modeling can be used to differentiate reflections from faults or fracture zones from other reflectivity, e.g. mafic bodies. Fault and fracture zones may have a large impedance contrast to surrounding rocks, while ductile shear zones usually do not. The ductile shear zones can instead be interpreted based on differing reflectivity patterns between domains and correlations with geology or magnetic maps. Paper IV presents 3D reflection seismic data from a quick-clay landslide site in southern Sweden. The area is located in a deformation zone and structures in unconsolidated sediments may have been influenced by faults in the bedrock. The main target layer is located at only 20 m depth, but good surface conditions during acquisition and careful processing enabled a clear seismic image of this shallow layer to be obtained.The research presented in this thesis provides increased knowledge about subsurface structures in four geologically important areas. The unconventional processing methods used are recommended to future researchers working with data from crooked-line recording geometries in crystalline environments. The imaging of shallow structures at the quick-clay landslide site shows that the 3D reflection seismic method can be used as a complement to other geophysical measurements for shallow landslide site investigations.

An integrated approach with remote sensing, GeographicInformation Systems (GIS) and more traditional fieldworktechniques was adopted to assess the groundwater potential inthe central highlands of Eritrea. Digitally enhanced colorcomposites and panchromatic images of Landsat TM and Spot wereinterpreted to produce thematic maps such as lithology andlineaments. The potential of the Advanced Spaceborne ThermalEmission and Reflection Radiometer (ASTER) data forlithological and lineament mapping was evaluated. Topographicparameters such as surface curvature, slope and drainagesystems were derived from digital elevation models and used tomap landforms. Digital elevation models (DEM) derived fromcontours and acquired in the Shuttle Radar Topographic Mission(SRTM) were compared in relation to location, drainage networksand lineament extraction. Fracture patterns and spacing weremeasured in the field in different rock types and compared withlineaments. Selected springs and wells were visited to studytheir topographic and hydrogeological setting. Well logs,pumping tests, water table depth in dry and wet season as wellas location of wells were collected. All thematic layersincluding hydrogeological data were integrated and analysed ina geographic information system. A groundwater potential mapwas generated and compared with yield data. Groundwaterrecharge was estimated based on water level fluctuations inlarge dug wells and chloride mass-balance method. Principal component analysis for rock type mapping providedbetter results with ASTER than with Landsat TM data. DEM datapermitted to create detailed landform maps useful torgroundwater potential assessment. DEM derived from SRTM dataare better for detection of drainage systems and linearfeatures than those derived from contours. Most of the fracturesystems corresponding to lineaments are either extensionalrelated to normal faults and dykes, or shear fractures relatedto strike-slip faults. N-S, NW-SE, WNW-ESE, NE-SW and ENE-WSWare dominant fracture orientations with often very densespacing. High yielding wells and springs are often related tolarge lineaments and corresponding structural features such asdykes. Typically wells and springs in basaltic areas havehigher yields mainly due to primary joints. Young alluvialsediments with high permeability and deeply weathered rocklayers are important for water supply especially in hydraulicconnection with fracture systems in crystalline bedrock.Groundwater potential zones demarcated through the model are inagreement with bore well yield data. The spatial distributionof groundwater potential zones shows regional patterns relatedto lithologies, lineaments, drainage systems and landforms.Recharge rates of 10 - 50 mm were estimated in this region. Theresults demonstrate that the integration of remote sensing,GIS, traditional fieldwork and models provide a powerful toolin the assessment and management of water resources anddevelopment of groundwater exploration plans. <b>Key words:</b>Remote sensing, Geographic InformationSystems, groundwater, geomorphology, Digital elevation model,lithology, hard rock, lineament, structures, hydrogeology,Eritrea

<p>An integrated approach with remote sensing, GeographicInformation Systems (GIS) and more traditional fieldworktechniques was adopted to assess the groundwater potential inthe central highlands of Eritrea. Digitally enhanced colorcomposites and panchromatic images of Landsat TM and Spot wereinterpreted to produce thematic maps such as lithology andlineaments. The potential of the Advanced Spaceborne ThermalEmission and Reflection Radiometer (ASTER) data forlithological and lineament mapping was evaluated. Topographicparameters such as surface curvature, slope and drainagesystems were derived from digital elevation models and used tomap landforms. Digital elevation models (DEM) derived fromcontours and acquired in the Shuttle Radar Topographic Mission(SRTM) were compared in relation to location, drainage networksand lineament extraction. Fracture patterns and spacing weremeasured in the field in different rock types and compared withlineaments. Selected springs and wells were visited to studytheir topographic and hydrogeological setting. Well logs,pumping tests, water table depth in dry and wet season as wellas location of wells were collected. All thematic layersincluding hydrogeological data were integrated and analysed ina geographic information system. A groundwater potential mapwas generated and compared with yield data. Groundwaterrecharge was estimated based on water level fluctuations inlarge dug wells and chloride mass-balance method.</p><p>Principal component analysis for rock type mapping providedbetter results with ASTER than with Landsat TM data. DEM datapermitted to create detailed landform maps useful torgroundwater potential assessment. DEM derived from SRTM dataare better for detection of drainage systems and linearfeatures than those derived from contours. Most of the fracturesystems corresponding to lineaments are either extensionalrelated to normal faults and dykes, or shear fractures relatedto strike-slip faults. N-S, NW-SE, WNW-ESE, NE-SW and ENE-WSWare dominant fracture orientations with often very densespacing. High yielding wells and springs are often related tolarge lineaments and corresponding structural features such asdykes. Typically wells and springs in basaltic areas havehigher yields mainly due to primary joints. Young alluvialsediments with high permeability and deeply weathered rocklayers are important for water supply especially in hydraulicconnection with fracture systems in crystalline bedrock.Groundwater potential zones demarcated through the model are inagreement with bore well yield data. The spatial distributionof groundwater potential zones shows regional patterns relatedto lithologies, lineaments, drainage systems and landforms.Recharge rates of 10 - 50 mm were estimated in this region. Theresults demonstrate that the integration of remote sensing,GIS, traditional fieldwork and models provide a powerful toolin the assessment and management of water resources anddevelopment of groundwater exploration plans.</p><p><b>Key words:</b>Remote sensing, Geographic InformationSystems, groundwater, geomorphology, Digital elevation model,lithology, hard rock, lineament, structures, hydrogeology,Eritrea</p>

Le territoire burkinabè est constitué à plus de 80% de formations de socle. Ces formations renferment des ressources en eau souterraine qui constitue la seule source en eau potable de certaines populations. Cependant, le quart des forages réalisés en vue d’exploiter ces eaux sont négatifs. Une bonne compréhension du fonctionnement hydrogéologique et hydrodynamique des aquifères de socle qui sont très hétérogènes peut aider à résoudre ce problème. L’objectif de la thèse est de proposer un modèle conceptuel hydrogéologique en milieu de socle fracturé soudano-sahélien en combinant différentes méthodes hydrogéophysiques et hydrogéologiques classiques. Le site expérimental de Sanon (environ 14 km2) a été choisi comme site d’étude en raison de sa géologie qui est représentative de certaines formations de socle de l’Afrique de l’Ouest. Les résultats indiquent que le profil d’altération de Sanon est cohérent avec d'autres modèles proposés ces dernières années, suggérant que la conductivité hydraulique des aquifères de socle est une conséquence des processus d'altération plutôt que de la fracturation tectonique. Concernant les propriétés hydrodynamiques, une corrélation linéaire positive d’environ 80% a été obtenue entre les transmissivités et les paramètres RMP. La présence d’un dôme piézométrique dans la vallée centrale a été observée en toute saison. La recharge se fait directement au niveau de ce dôme piézométrique (11 et 13% de la pluie annuelle) et l’alimentation des zones périphériques se ferait plutôt par des transferts latéraux. L’ensemble des informations géologiques et hydrogéologiques a permis de faire une simulation numérique qui reproduit l’écoulement observé. / More than 80% of Burkina Faso subsoil is composed of hard rocks. These hard rocks contain ground water resources which are the only drinking water for some people. Yet, the quarter of the boreholes drilled to exploit these waters are negative. A good understanding of the hydrogeological and hydrodynamic functioning of hard rock aquifers which are very heterogeneous can help to solve that problem. The objective of the thesis is to propose a hydrogeological conceptual model of hard rock aquifer under Sudano-Sahelian climate by combining different hydrogeophysical and hydrogeological methods. The Sanon experimental site (14 km² catchment area) was chosen as the study site because of its geology, which is representative of some hard rocks in West Africa. The results show that Sanon weathering profile model is consistent with other models proposed in recent years, suggesting that the hydraulic conductivity of hard rock aquifers is a consequence of weathering processes, rather than tectonic fracturing. Concerning hydrodynamic properties, a positive linear correlation of about 80% was obtained between the transmissivities and the MRS parameters. The presence of a piezometric dome in the central valley on all the piezometric maps produced in both low and high waters was observed. As for recharging, it is done directly in the zone of the piezometric dome (between 11 and 13% of annual rainfall) and the feeding of the peripheral zones would be rather by lateral transfers. The set of geological and hydrogeological data allowed the performance of a numerical simulation in steady state which reproduces well the observed flow.

"Safety is a value, not just a Priority" Geomechanically stable underground excavations require continuous assessment of rock mass behavior for maximizing safety. Optimizing pillar design is essential for preventing hazardous incidents and improving production in room-and-pillar mines. Maintaining regional and global stability is complicated for underground carbonate or stone deposits, where extensive fracture networks and groundwater flow become leading factors for generating unsteady ground conditions including karsts. A sudden encounter with karst cavities during mine advance may lead to safety issues, including ground collapse and outflow of unconsolidated sediments and groundwater. The presence of these eroded zones in pillars may cause their failure and poses a risk to the lives of miners apart from disrupting the pre-planned mining operations. A pervasive presence of joints and fractures plays a primary role in promoting structurally controlled failures in stone mines, which accelerates upon interaction with the karst cavities. The prevalent empirical and analytical approaches for pillar design ignore the geotechnical complexities such as the spatial density of discontinuities, karst voids, and deviation from the design during short-range mine planning. With the increasing market demand for limestone products, mining organizations, as well as enforcement agencies, are investing in research for increasing the efficiency of extracting valuable resources. While economical productivity is essential, preventing risks and ensuring the safety of miners remains the cardinal objective of mining operations. According to the Mine Safety and Health Administration (MSHA), since 2000, about 31% of occupational fatalities at all underground mines in the United States are caused due to ground collapse, which rises to 39% for underground stone mines. The objective of this study is to provide a reliable and methodological approach for pillar design in underground room-and-pillar hard rock mines for safe and efficient ore recovery. The numerical modeling techniques, implemented for a case study stone mine, could provide a pragmatic framework to assess the effect of karsts on rock mass behavior, and design future pillars detected with voids. The research uses data acquired from using remote sensing techniques, such as LiDAR and Ground-penetrating Radar surveys, to map the excavation characteristics. Discontinuum modeling was valuable for analyzing the pillar strength in the presence of discontinuities and cavities, as well as estimating a safe design standard. Discrete Fracture Networks, created using statistical information from discontinuity mapping, were employed to simulate the joints pervading the rock mass. This proposed research includes the calibration of rock mass properties to translate the effect of discontinuities to continuum models. Continuum modeling proved effective in analyzing regional stability along with characterizing the redistributed stress regime by imitating the excavation sequence. The results from pillar-scale and local-scale analyses are converged to optimize pillar design on a global scale and estimate the feasibility of secondary recovery in stone mines with a dominating discontinuity network and karst terrane. Stochastic analysis using finite volume modeling helped evaluate the performance of modified pillars to assist production while maintaining safety standards. The proposed research is valuable for improving future design parameters, excavation practices, and maintaining a balance between an approach towards increased safety while enhancing production. / Doctor of Philosophy / "The most valuable resource to come back out of a mine is a miner" – Anonymous. The United States accounted for 27% of the global limestone market share which was valued at US$58.5 billion in 2020 [148]. It is projected to reach a target of US$65.3 billion in 2027, growing even in midst of the COVID-19. As surface reserves deplete, much of the mineral demand gap is supplemented by mining underground deposits. Underground mines extract minerals from deep within the earth compared to surface mines. As a result, the miners experience a greater number of accidents in a constricted environment because of roof/tunnel collapse, fewer escape routes, ventilation, explosions, or inundation. According to the Mine Safety and Health Administration (MSHA), about 15% of all underground mine injuries in the US were caused by rockfalls since 1983. The majority of underground stone deposits are mined using the room-and-pillar mining method, which resembles a chessboard design where the light squares are mined, and the dark squares are left as rock pillars to support the tunnels. Limestone, a carbonate rock, contains a lot of fractures and joints (discontinuities). Erosion of rocks due to continuous water flow through the fractures leads to the formation of cavities known as karsts. Interaction of karsts with the prevalent fracture network increases rockfall risk during mining. The collapse of voids along with an inrush of filled rock-clay-water sludge can harm miners' lives, damage machinery, and stop further operations. Literature is scarce on topics that quantify the risk and disruption posed by these cavities in underground mines. Most rock classification systems cannot classify their effect because of the unpredictability and extensive analysis required. The objective of this research is to provide a reliable and methodological approach for designing pillars in underground hard rock mines for ensuring a safe working environment and efficient mineral recovery. This research starts with analyzing the strength of pillars, in which karst cavities were discovered while mining. The safety concerns often lead the miners to not excavate around the cavities and leave valuable resources unmined. Data from ground-penetrating radar and laser scanning surveys were used to characterize the voids and map the discontinuities. Discrete-element numerical modeling was used to simulate the pillars as an assembly of blocks jointed by the discontinuities. The simulation results help us understand the instability issues in the karst-ridden pillars and ways to improve upon the existing design. The findings were used to modulate the parameters for regional-scale models using finite volume modeling for less computationally intensive analyses and simulating rock as a continuum. The continuum models were highly effective in analyzing the instability issues due to the prevalent karstic network. This helps understand any alternative scenario that could have been implemented to optimize ore recovery while preventing risks. The results from the single pillar and regional analyses are combined to optimize pillar design on a global mine scale. This dissertation focuses on improving hazard mitigation in mines with unpredicted anomalies like karsts. Although this research is based on a specific mine site, it empowers the operators to explore the presented techniques to increase safety in all underground mines. The suggested methodology will help devise better strategies for handling instability issues without jeopardizing the mine operations. The primary motivation is to keep the underground miners safe from hazardous situations while fulfilling the secondary objective of maximizing mineral production.