Significant uncertainty surrounds the influence of atmospheric and oceanic forcing on the fluctuations of tidewater glacier outlets of the Greenland ice sheet (GrIS), with the majority of studies focussing on dynamics over the last two decades. Although numerical model based projections exist anticipating the future dynamics of major GrIS outlets, these have been made using temporally limited model calibration periods (<5 years) compared to the centennial timescales that they seek to predict over. The ability of these numerical models to simulate the centennial timescale dynamics of GrIS tidewater glaciers has therefore not been explicitly tested. This thesis seeks to calibrate a well-established one-dimensional tidewater glacier numerical model against post-Little Ice Age maximum (LIAmax) observations of a major tidewater glacier outlet of GrIS. The study site chosen is Kangiata Nunaata Sermia (KNS); the largest tidewater outlet in SW Greenland south of Jakobshavn Isbræ. This glacier is known to have undergone retreat of >20 km since its LIAmax, though the timing of this retreat and response to climate forcing is currently poorly constrained. Utilising a range of source material, it is demonstrated that KNS is likely to have achieved its LIAmax by 1761, experiencing either one, or two multi-kilometre retreats by 1859, and retreats of a similar scale between 1921-1968, and 1997-2012. Terminus fluctuations of KNS were in phase with climate anomalies, where data were available for comparison (1871-2012). To allow accurate comparison to numerical model output, the accuracy of different methods of quantifying glacier terminus change was also evaluated. Two new methods were devised so observations could be matched with greater accuracy than existing methods allowed. Glacier sensitivity to climate forcing was evaluated using the numerical model.

>Magister Scientiae - MSc / Separation between the South American and African plate’s occurred along the present day Atlantic margin during the Middle to Late Jurassic leading to the formation of a passive margin along the west coast of Southern Africa. The margin then later developed into the large Orange Basin flanking the west coasts of South Africa and Namibia. The Orange Basin on the west coast of South Africa covers an area of roughly 130 000 square kilometers relevant to the 200 m isobath and has roughly one well drilled for every 4000 square kilometers. The basin has proven hydrocarbon reserves and potential for further discoveries. The study area is located within South African exploration licencing blocks 3A/4A and 3B/4B and covers a region of roughly 97 km by 150 km. The study aims at understanding the geological processes responsible for the formation of the Orange Basin with a focus on the evolution of source rock maturity. The methodology involved utilizing the Petrel software for seismic interpretation and well correlation utilising twodimensional seismic data and all the relevant well data including geological well logs, petrophysical well logs, well top data, check-shot data, borehole temperature data and geochemical well data such as Rock Eval and vitrinite reflectance data. PetroMod (IES, Version 10) was utilized to simulate the Orange Basin evolution and the affect on source rock maturity. Seismic interpretation of the Post-Hauterivian succession shows a relative thickening of the sedimentary sequence westward as the basin evolves from the early drift to complete drift phase. Results from the petroleum system modeling indicate that the Barremian - Early Aptian source rock is at present overmature and producing mostly gas in the shelf areas whereas the potential for oil are most likely present in the deep water area of the basin where Tertiary progradation has resulted in renewed petroleum generation. Petroleum system modeling results indicate that the younger Cenomanian - Turonian source rock is less mature than the older Barremian - Early Aptian source rock as indicated by a lower transformation ratio and is mainly producing oil.

Thesis (M. Sc.)--University of Alberta, 2009. / Title from PDF file main screen (viewed on Feb. 19, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Mining Engineering, Department of Civil and Environmental Engineering, University of Alberta. Includes bibliographical references.

A constitutive model based on rate-independent elastoplasticity concepts is developed and used to simulate the behavior of geologic materials under arbitrary three-dimensional stress paths. The model accounts for various factors such as friction, stress path and stress history that influence the behavior of geologic materials. A hierarchical approach is adopted whereby models of progressively increasing sophistication are developed from a basic isotropic-hardening associative model. Nonassociativeness is introduced as correction or perturbation to the basic model. Deviation of normality of the plastic strain increments to the yield surface F is captured through nonassociativeness. The plastic potential Q is obtained by applying a correction to F. This simplified approach restricts the number of extra parameters required to define the plastic potential Q. The material constants associated with the model are identified, and they are evaluated for three different sands (Leighton Buzzard, Munich and McCormick Ranch). The model is then verified by comparing predictions with laboratory tests from which the constants were found, and typical tests not used for finding the constants. The effect of varying initial density of a material on the stress-strain and volumetric response is investigated. An empirical relation is proposed, whereby one parameter is modified based on the initial density, such that improved predictions can be obtained without increasing the total number of parameters. Implementation of the nonassociative model in a finite element program to solve boundary value problems leads to a nonsymmetric stiffness matrix. Besides, using a nonsymmetric solver, three numerical schemes are investigated. The idea of the schemes is to modify the stiffness matrix such that a symmetric equation solver can be used. Prediction of stress-strain, volumetric response and CPU time for different schemes are compared with the predictions obtained using the nonsymmetric solver. The nonsymmetric equation solver used less CPU time and the solutions were more accurate. Based on the above findings, a soil-footing system is analyzed using the finite element techniques. The associative and nonassociative models are used to predict the behavior. For the nonassociative model, solution is obtained by using a nonsymmetric solver. Results obtained from both models are compared with a model footing test performed in the laboratory.

Thesis (Ph.D.) -- University of Adelaide, National Centre for Petroleum Geology and Geophysics, 2000. / Four folded maps in pocket on back cover. Copy of author's previously published work inserted. Includes bibliographical references (9 leaves).

Thesis (M.A.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains vi, 43 p. : ill. (some col.) Vita. Includes abstract. Includes bibliographical references (p. 38-40).

M.Sc. / The objective of this work is to establish a regional, three-dimensional sedimentological model of the clastic strata of the Vryheid Formation and pre-existing basin floor topography of the Witbank Coalfield, South Africa. This considers an area extending from 25°30’ S to 26°30’ S by 28°30’E to 30°E. This has been undertaken using computer modelling to examine the three-dimensional distribution of the sedimentary rocks. The basis for the geological model presented in this thesis is 1190 borehole logs collected from three mining companies involved in coal extraction in the study area, namely Anglo American Coal Corporation, Duiker Mining Limited and Ingwe Coal Corporation Limited. These borehole logs are converted to a common data format for inclusion into the 3-D model. These borehole logs are correctly positioned in space using a digital elevation model. The primary objective of this research was to visualize the interburden and overburden sedimentary rocks within the study area, so as to be able to understand the distribution and hence origin of these rocks. As commercially available modelling tools have several restrictions with respect to the current work, Geovision cc. was contracted to develop the tools needed for the geological visualization of the data. Using the three-dimensional model, the distribution of the various facies and facies associations can be defined, to understand the depositional history of the basin. These characteristics include the delineation of the general trend of the basement topography. The distribution of the lower glacial and paraglacial sedimentary rocks within the study in steep-sided palaeovalleys, marked by rapid facies and thickness changes from diamictite through argillite, and minor sandstones and conglomerates is shown in 3-D. Evidence of lobate deltas and bedload sandy river deposits between the No. 2 and No. 4 Seams is presented in 3-D. The 3-D characteristics of the rocks between the No. 4 and No. 5 Seams, proposed to represent a period of deltaic progradation during an overall marine transgression is described. By using a 3-D model it is possible to evaluate the distribution of sedimentary rocks, both through space and through time. These palaeoenvironmental interpretations facilitate a better understanding of the genesis of the Witbank Coalfield. Furthermore, this enhanced geological modelling can facilitate improved mine planning and mining techniques.

Four folded maps in pocket on back cover. / Copy of author's previously published work inserted. / Includes bibliographical references (9 leaves). / 1 v. : ill. (chiefly col.), maps (some fold.), (chiefly col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / An integrated biostratigraphic, wireline, seismic, lithological and 3D-Chronostrat sequence stratigraphic study has been conducted to investigate the evolution of the Albian to recent section of the Dampier Sub-basin on Australia's North West Shelf,. / Thesis (Ph.D.)--University of Adelaide, National Centre for Petroleum Geology and Geophysics, 2000

Thesis (Ph. D.)--University of Massachusetts Amherst, 2009. / Open access. Includes bibliographical references (p. 137-144). Print copy also available.

Four folded maps in pocket on back cover. Copy of author's previously published work inserted. Includes bibliographical references (9 leaves). An integrated biostratigraphic, wireline, seismic, lithological and 3D-Chronostrat sequence stratigraphic study has been conducted to investigate the evolution of the Albian to recent section of the Dampier Sub-basin on Australia's North West Shelf,.