Μηχανική συμπεριφορά και φαινόμενα ερπυσμού σε μαλακά αργιλικής σύστασης πετρώματα κάτω από συνθήκες σταθερής φόρτισης. / Rock creep at clays under conditions of high strength.

No description available.

No description available.

<p>This thesis follows and builds upon a previous study at the rock engraving site of Driekopseiland (Morris 2002). The earlier findings are here contrasted with another site in the area, namely Wildebeest Kuil, as a means to highlight the variability which is a feature of the rock art of the Northern Cape as a whole. The main thrust of the thesis, which refers to a number of other rock art sites in the region, is to model the implications of this variability relative to social context and history in the precolonial past. Significant empirical obstacles, particularly the difficulties associated with dating rock art, render some aspects of the enterprise intractable for the time being. But opportunities are pursued to advance and evaluate ideas as to the social mechanisms and processes which might be implicated in the making and re-making of images on rock and in the generation of the diversity that is manifest in the rock art as it is found today. Whereas other approaches have tended to explain difference relative to social entities such as &lsquo / cultures&rsquo / or &lsquo / ethnic groups&rsquo / , this thesis offers, as a point of departure, a critique of received concepts, reconsidering some of the fundamental metaphors and assessing the elaboration of analogies that have been used in the past. It proposes that better theoretical footholds might be those that explain variability relative to process and movement. It invokes Tim Ingold&rsquo / s concept of a meshwork of dynamic relationships of people immersed in the world, of &lsquo / entanglements&rsquo / that refer to multiple mechanisms that might explain how rock art has changed in place and time. The pertinence of these ideas is shown with reference to specific instances in the Northern Cape.As a parallel weave in this study, there is a concern over the social role of archaeology, with discussion on the burgeoning salience of rock art beyond the academy, in the heritage and tourism sectors and amongst descendants of the Khoean. The thesis gives consideration to the role of museums and research in terms of &ldquo / heritage in practice,&rdquo / and seeks to develop a discourse in which, following Alexander, &ldquo / everything can be perceived as changing and changeable&rdquo / &ndash / an underlying theme throughout the study. The thesis does not bring empirical closure to the topic but suggests a programme for future engagement, having opened up and shown the relevance of wider theoretical insights for addressing the variability in the rock art of the Northern Cape.</p>

<p>This thesis follows and builds upon a previous study at the rock engraving site of Driekopseiland (Morris 2002). The earlier findings are here contrasted with another site in the area, namely Wildebeest Kuil, as a means to highlight the variability which is a feature of the rock art of the Northern Cape as a whole. The main thrust of the thesis, which refers to a number of other rock art sites in the region, is to model the implications of this variability relative to social context and history in the precolonial past. Significant empirical obstacles, particularly the difficulties associated with dating rock art, render some aspects of the enterprise intractable for the time being. But opportunities are pursued to advance and evaluate ideas as to the social mechanisms and processes which might be implicated in the making and re-making of images on rock and in the generation of the diversity that is manifest in the rock art as it is found today. Whereas other approaches have tended to explain difference relative to social entities such as &lsquo / cultures&rsquo / or &lsquo / ethnic groups&rsquo / , this thesis offers, as a point of departure, a critique of received concepts, reconsidering some of the fundamental metaphors and assessing the elaboration of analogies that have been used in the past. It proposes that better theoretical footholds might be those that explain variability relative to process and movement. It invokes Tim Ingold&rsquo / s concept of a meshwork of dynamic relationships of people immersed in the world, of &lsquo / entanglements&rsquo / that refer to multiple mechanisms that might explain how rock art has changed in place and time. The pertinence of these ideas is shown with reference to specific instances in the Northern Cape.As a parallel weave in this study, there is a concern over the social role of archaeology, with discussion on the burgeoning salience of rock art beyond the academy, in the heritage and tourism sectors and amongst descendants of the Khoean. The thesis gives consideration to the role of museums and research in terms of &ldquo / heritage in practice,&rdquo / and seeks to develop a discourse in which, following Alexander, &ldquo / everything can be perceived as changing and changeable&rdquo / &ndash / an underlying theme throughout the study. The thesis does not bring empirical closure to the topic but suggests a programme for future engagement, having opened up and shown the relevance of wider theoretical insights for addressing the variability in the rock art of the Northern Cape.</p>

No description available.

In several field studies it was concluded that highly transmissive features transmit the majority of solute mass in horizontally-fractured bedrock aquifers. The purpose of this investigation is to develop a new technique for determining the location and relative role of hydraulically connected fracture features with respect to solute transport. To explore this, a radial-divergent tracer experiment was conducted in a four-borehole array completed through a horizontally-fractured dolomite of Silurian age in Smithville, Ontario, Canada. The injection interval included several hydraulically-identified features located in the Upper Eramosa member of the Lockport formation. 496 L of Lissamine FF (a conservative fluorescent dye tracer at a concentration of 200 mg/L) was injected at a rate of 23.25 L/min +/- 1 %. The arrival of fluorescent tracer was detected in a series of open monitoring wells located in a down gradient direction using a submersible fluorometer equipped with a pressure transducer. Correlating the fluorescence signals at depth with hydraulically-identified features provided an in-situ measure that identified the vertical intersection and relative role of each feature with respect to mass transport. FRAC3DVS a discrete fracture finite element model was used to simulate the tracer experiment. Based on the results of the tracer experiment and numerical simulations, it is concluded that the highly transmissive features identified using hydraulic techniques do not always carry all of the mass in transport. The majority of mass transport, however, followed at least one of the largest features in every borehole, just not every large feature. Results of this experiment suggest it is imperative that a distinction between large fracture features that transmit and do not transmit mass be made. / Thesis (Master, Civil Engineering) -- Queen's University, 2008-07-14 21:22:05.427

Characterization of field-scale transport in bedrock aquifers is necessary due to the preponderance of groundwater contamination in these settings, and the increasing attention paid to these sites by regulatory bodies. However, as a result of the inherent complexity, and the consequent uncertainty in the dominant transport processes, large-scale transport in fractured rock is poorly understood. In this study an investigation of large-scale transport was accomplished in part by conducting a radial-divergent tracer experiment in a 15 m thick section of aquifer with observations over a 245 m distance, using a novel tracer detection method capable of detecting breakthrough in individual fractures. The tracer experiment was conducted at a well-characterized field site in Smithville, Ontario, which is underlain by several large-scale bedding plane fractures, and used a submersible fluorometer to detect tracer arrival in-situ and to obtain vertical fluorescence profiles (VFPs) from observation boreholes. To complete the investigation, hydraulic characterization data and VFPs were used to approximate the dominant transport pathways and a numerical model which solves for flow and transport in discrete fracture features (HydroGeoSphere) was used to simulate the tracer experiment. The results of the experiment and the modeling exercise were compared to those from a large-scale single fracture tracer experiment conducted previously at the same site, for which the modeling was revisited. The experimental results of the fracture network experiment (FNE) were markedly more heterogeneous than those of the previously conducted single fracture experiment (SFE), with multiple peaks in the breakthrough curves, and scale dependent changes in breakthrough character. The VFPs illustrate that differences in the observed transport arise due to tortuous transport pathways within individual fracture features, and the combined effect of this tortuosity in the numerous fractures contributing to transport in the fracture network. For the observation boreholes closest to the source (< 55 m), both the FNE and SFE models were capable of fitting the data using parameters within the range of values determined from prior lab and field experiments at the site. These fits became poorer over increased transport distances however, where the models used could not account for the increased effects of tortuosity. / Thesis (Master, Civil Engineering) -- Queen's University, 2008-08-25 02:48:16.066

No description available.

No description available.