The Antarctic Ice Sheets responded significantly to climatic conditions during the Last Glacial Maximum (LGM) and the subsequent warming that followed. Therefore, an understanding of how Antarctica reacted to past climates is necessary to predict the response of its ice sheets to current and future climate change. This thesis presents new evidence about the timing and magnitude of East and West Antarctic ice sheet (EAIS & WAIS) changes during the Quaternary Period, from the Darwin Hatherton glacial system (DHGS, 79.5S, 158E). The DHGS drains the EAIS through the Transantarctic Mountains into the Ross Ice Shelf and glacial deposits have been used to constrain ice sheet thicknesses in this sector of the Ross Sea Embayment. At four sites along the length of the system, glacial deposits were mapped and 73 erratic and bedrock samples collected for ¹⁰Be and ²⁶Al surface exposure dating (SED). The exposure ages range from 0.01 to 2.2 Ma and generally show a trend of oldest ages at the highest elevations, thus suggesting an overall decrease of ice volume within the DHGS over the Quaternary. The older ages suggest that during the Plio-Pleistocene, DHGS ice was at least 800-1000 metres thicker than present, while in the mid to late-Holocene thickening was less than 50-80 metres. Four glacial advance and retreat events were described and mapped previously from the DHGS by Bockheim et al (1989). The Isca and Danum drifts, are ~1-2 and 0.6 Ma respectively. The Britannia-II Drift, previously assumed to mark the maximum extent of the Last Glacial Maximum advance is more complex, with clusters of ages at ~6.5, ~36 and ~125 ka. The youngest drift, the Hatherton is mid to late-Holocene (<4.5 ka) and suggests that the DHGS has been near its equilibrium position during this period. Throughout the DHGS no unequivocal evidence of the LGM was observed and therefore poses questions about the past thickness of the Antarctic ice sheets during the LGM. Exposure ages from sites near the head of the Hatherton Glacier (Dubris Valley & Lake Wellman) suggest that at the LGM, the East Antarctic Ice Sheet may have been of similar size, or slightly smaller, than present. In stark contrast, at the confluence of the Darwin Glacier and the Ross Ice Shelf, a WAIS ~400-900 metres above the modern ice surface is tentatively suggested; A value in agreement with that proposed by modern glaciological models. Additionally, while the results from the Dubris and Bibra valleys show that the EAIS thins during glacial climates (i.e. the LGM), it also suggests thickening during interglacials. The Britannia-I and II drifts representing retreats at~6.5 and ~125 ka from glacial highstands. A number of key findings related to the application of SED in Antarctic settings are also presented. The use of dual-nuclides (¹⁰Be & ²⁶Al) show that within the DHGS, the proportion of samples displaying a prior burial history increases with distance from the catchment. The spread of exposure ages observed in the dataset also show the complexity of the depositional processes occurring at cold-based glacial margins and therefore judicious sample selection is required to obtain exposure ages that are representative of the true deglaciation age.

Microbial mats are important components of perennially ice-covered Antarctic lakes in the McMurdo Dry Valleys, where they often comprise the dominant biomass in this cold, shaded environment. These lakes represent some of the most extreme lacustrine environments on Earth, including a persistent ice-cover, stable, stratified water columns, with strong salinity related density gradients. In these low-disturbance environments, the microbial consortia develop macroscopic emergent structures such as pinnacles and ridges. Such structures are speculated to confer advantageous survival traits and have also been found in the Precambrian fossil record as “conophyton” stromatolites – arguably some of the earliest evidence of life – and it has been suggested that a better understanding of the growth dynamics of modern “conophyton” will inform our understanding of what was required for these early fossils to be produced. Despite decades of research, there are few studies of the structural basis of conophyton producing microbial mats in Antarctic lakes. To help address this gap, complex microbial mats along a transect established in Lake Fryxell, one of the McMurdo Dry Valley lakes, were examined; with the aim of documenting the distribution of different types of photosynthetic organisms and mat morphologies along environmental gradients such as light, conductivity, oxygen concentration and depth. Microbial mat samples were taken along the transect and analysed in New Zealand using confocal laser scanning microscopy, along with conventional pigment extraction techniques. Correlations between mat morphology, pigment content and lake properties were found. The appearance of bacteriochlorophylls, characteristic of green sulfur bacteria within and below the oxycline confirm a shift from aerobic to anaerobic metabolism that was consistent with mats taking on a prostrate appearance. The cyanobacterial pigment phycoerythrin was only found in the hyperoxic, relatively well lit region of the transect, and was associated with the mats forming a distinctive macroscale morphology with dense fields of cm-scale cuspate pinnacles. Between these, a hypoxic region was characterised by a relatively flat mat within which were many cm-scale pits. Structural investigations were focussed on two distinct morphologies, pinnacle and honeycomb mat. Nearly all photosynthetic organisms were located in the upper 2 mm of both pinnacle and honeycomb mats, mainly comprising diatoms and cyanobacteria. Pinnacle mats were dominated by a narrow cyanobacterium, probably a species of Leptolyngbya, which were mostly oriented vertically, which placed trichomes parallel to the direction of pinnacle extension. The honeycomb mat contained fewer narrow trichomes, rather the bulk of photosynthetic organisms were diatoms from the genera Muellaria, Navicula and Diadesmis, together with broad-trichome cyanobacteria that formed a thin skin on the surface of the mat, though absent from the pits. The type of emergent structure that is formed appears to be related to species composition, and this in turn appears to be related to the growth conditions. A model was developed to explain how species-specific growth mechanisms are involved in emergent structure formation for honeycomb and pinnacle mats.

Antarctica is widely perceived as the most untouched continent on Earth. However, increasing anthropogenic presence in Antarctica is creating continual pressure on the pristine environment. To protect the Antarctic environment, monitoring and reporting procedures must be a priority for Nations wishing to conduct research on the continent. A significant contributor to environmental degradation is poor waste management and waste disposal, in particular the discharge of sewage and wastewater into the marine environment. This study provides information on the potential impact of Scott Base wastewater on the local marine environment, which can be used to improve operating systems and as a tool to ultimately reduce the environmental footprint of the base. This study investigated the characteristics of the sewage from Scott Base, Antarctica, and the water quality within the wastewater discharge plume beneath the sea ice. Results from seawater analysis were then compared with Redvers (2000) to give an indication of how contamination levels have changed over the last decade. Results show that in the vicinity of the wastewater outfall, seawater samples contained no faecal coliforms or Escherichia coli. Nitrate-Nitrogen (NO3ˉ- N) concentrations were recorded up to 1.1 mg/L, while phosphate (PO43-) ranged from 0.28 to 0.45 mg/L. The pH ranged from 7.84 to 7.92. Dissolved oxygen ranged between 10.05 and 13.02 mg/L, and conductivity between 48.4 to 55.2 mS/cm. Concentrations of copper (Cu), manganese (Mn), and zinc (Zn) were greatest at sites within 30m of the outfall. Iron (Fe) and nickel (Ni) were detected at most sites within the plume. The general spatial extent of the plume is now approximately 50m long-shore, and 30m offshore. Compared to Redvers (2000) the current plume is more localised, with a reduction of approximately 100-125m long-shore and 10-20m offshore. Faecal coliforms have reduced to no longer be detected within the plume, while dissolved oxygen and total organic carbon concentrations in the plume have increased, and conductivity has decreased. Soils surrounding Scott Base were also investigated as a potential source of trace metal (As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) discharge to the marine environment. Total recoverable soil metal concentrations and readily leachable metal concentrations were measured. Sites were selected on the basis of being potential sources of contamination (fuel storage areas or refuelling areas), or potentially effecting the marine environment (shorelines). Results show that the greatest concentrations of metals and readily leachable metals were found primarily along the shoreline, and not necessarily where contamination related to current base activities is likely to occur. The results indicate that historic contamination may still persist in the terrestrial environment, and has the potential to be transported into the marine environment. Domestic and drinking water samples were analysed for trace metals and nutrients to ensure that contaminants from the wastewater outfall were not entering the reverse osmosis plant. Results show that the drinking water meets New Zealand Drinking Water Standards (Ministry of Health, 2008).

The thesis is a study of labour regulation and the State in the Sudan in the light of a general theoretical conception of labour law and the State. The first Chapter defines the concepts of analysis that are used throughout the study, isolates the "essential" properties of the Capitalist State and Law from the historically concrete forms which they assume in a particular society and distinguishes between processes which influence development of the form of law and others which influence its sociological development. Drawing on the analysis in Chapter I, Chapter II exposes the inter-relationship between the Sudanese social formation, State and Law and the implication of this inter-relationship for both the form and substance of labour relations law. Chapters III, IV and V are specific verifications of the hypothesis regarding the inter-relationship between the State and labour relations law in the Sudan and that regarding the development of the "substance" and "ideology" of law in general. The thesis considers law as an empirically-founded discipline. But, it distinguishes between various types of empirical facts about law corresponding with respective semi-autonomous social levels at which law asserts its existence. The research method followed describes the empirical facts about law at the particular level and, in order to determine the epistemological significance of these facts, analytically relates them to empirical facts at other levels. Wherever used in the thesis the term "theory" signifies either this methodological procedure of analysing the inter-connection of empirical facts at a certain level and their inter-relation with other facts at other levels, or the substantive generalizations about law which findings at these various levels would allow. I consider my application of this methodology to the study of labour rela tions law, the historical dimension this application introduces in socio-economic analysis of this law, the criticism of certain Marxist and other sociological conceptions of law it enables, and the socio-histor ical relativity of the "substance" and "ideology" of law it reveals as original contributions to the knowledge of labour law. The compilation and evaluation within the framework of the thesis of empirical materials on industrial relations in the Sudan are likewise original contribution to the knowledge of Sudanese "labour law" and labour law in general.

This thesis is a study of banking regulation in Nigeria. It has three main objectives: to explain the evolution and impact of banking regulation after independence to discuss the reasons for the persistent failure of financial regulation; and to highlight the role of external agencies in Nigeria's financial system. The thesis offers a historical perspective on the developments in Nigerian banking regulation, but focuses mainly on the period after independence. It examines the economic and political theories that have influenced financial regulatory trends in Nigeria. It considers these theories in their political and legal context. The thesis does not embrace any theory in particular. Instead, its approach is pragmatic and comparative focusing on the interaction between legal, political and institutional factors that have influenced financial regulation in Nigeria. The study shows that the pre-liberalisation regulatory norms were repressive and inefficient. It argues that banking deregulation was introduced as an economic revolution devoid of necessary corresponding political and legal changes. The core destabilising factors are identified as inadequate regulatory powers, political corruption, political instability, legal instability, policy distortions, and incongruous laws. The complicity of the IMF and World Bank in this process is also discussed. Financial deregulation was prompted by predatory politics characteristic of the Nigerian state; yet, deregulation has aggravated the country's political instability and exacerbated prebendalism. The thesis discusses policy options to break this vicious circle.

This thesis studies the scattering properties of different types of imperfections in large Arctic and Antarctic ice sheets. Such irregularities include cracks, pressure ridges and both open and refrozen leads. The scattering by a transition region between sea ice and a very thick ice shelf, for example as is found in the Ross Sea in Antarctica, is also treated. Methods of solution are based on applications of Green�s theorem to the appropriate situation, which leads to either a single integral equation or a pair of coupled integral equations to be solved at the boundary between the ice and the sea water. Those equations over a finite interval are solved using numerical quadrature, while those over semi-infinite ranges are solved using the Wiener-Hopf method. Results calculated using different techniques are able to be checked against each other, giving us great confidence in their accuracy. In particular, the scattering by three ice sheets of different thicknesses is confirmed analytically by mode-matching coupled with the residue calculus technique. The scattering by the single irregularities is investigated partly for its own sake, and partly with the aim of using it to treat the scattering when large numbers of features are included in a single ice sheet. The principal objective of doing this is to observe the change in the general amounts of reflection and transmission as the background ice thickness is changed. There is enough variation in our results for us to conclude that there is definite potential for using the change in an incident wave spectrum after passing through a given ice field to estimate the background ice thickness.

No description available.

Thesis (M.A. National Security Affairs)--Naval Postgraduate School, 1990. / Thesis Advisor(s): Bruneau, Thomas C. Second Reader: Breemer, Jan S. "June 1990." DTIC Identifier(s): International politics, Treaties, Security, Cooperation, South America, South Africa, Competition, Natural resources, Sea lanes of communication, Naval operations, Foreign policy, Balance of power, Sovereignty, Spheres of influence, National interests. Author(s) subject terms: U.S. Interests, South Atlantic, Southern Cone, Antarctica. Includes bibliographical references (p. 101-104). Also available online.

Thesis (Ph. D.)--University of Washington, 1993. / Vita. Includes bibliographical references (leaves [131]-137).

Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (p. 99-110).