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Extensional subsidence, inversion and volumetric contraction in the Bass Basin of Australia : a seismic study / Pradipta Kumar Das.Das, Pradipta Kumar January 2001 (has links)
"August, 2001" / Bibliography: leaves 173-183. / xvi, 184, 12 leaves : ill. (some col.), maps, plates (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / "The primary objective of the study was to gain a better understanding of the tectonostratigraphic evolutionary history of the Bass Basin. In particular, the study has focussed on mapping and analysing all the faults and fault patterns in the Bass Basin in relation to the subsidence history and its influence on sedimentation and hydrocarbon potential of the basin. The reason why the Durroon area and the Bass area behaved differently in response to extensional stresses was investigated. As a final outcome, it was thought important to clarify some of the existing disagreement about the broad tectonic and structural history of the basin and in particular to separate the influence of the Otway and Tasman Sea rifting episodes on the sedimentation history of the Bass and Durroon area. The study also aimed at investigating the occurence in the basin and nature of a recently recognised fault system, a polygonal fault system." --p. 2. / Thesis (Ph.D.)--University of Adelaide, National Centre for Petroleum Geology and Geophysics, 2002
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Facies heterogeneity, platform architecture and fracture patterns of the Devonian reef complexes, Canning Basin, Western AustraliaFrost, Edmund Locke, 1974- 28 August 2008 (has links)
Carbonate facies patterns and stratal architecture are the product of the complex interaction of internal (e.g., reef-building biota, sediment production) and external drivers (e.g., tectonics, climate, and relative sea level). In the Canning Basin of Western Australia, many of these drivers are in flux across the Late Devonian Frasnian--Famennian (F--F) boundary and significant variations in reefbuilding biota and long-term accommodation are observed. This study documents the evolution of the Canning Basin's Devonian reef complexes across the F--F boundary and proposes a new interpretation of the stratal architecture and paleobathymetric profile of the Famennian. Data presented here demonstrate the evolutionof a shelf-crest system in the Famennian, with beds expanding basinward and the reef growing in water depths of approximately 5-15 m. The paleobathymetric profile of the Famennian described by this study represents a departure from the well-documented barrier-reef system of the Frasnian. Digital outcrop models help capture the heterogeneity of the Famennian system and allow for characterization of the Devonian reef complexes across the F--F boundary. Syndepositional fractures are a ubiquitous feature of high-relief, reefrimmed carbonate systems and these features exert a profound influence on many facets of platform evolution. This study documents strong variability in syndepositional fracture patterns as a function of lithofacies and depositional setting and evidence for the temporal evolution of the mechanical properties of the Devonian reef complexes is presented. A statistically significant relationship is documented between syndepositional fracture development and variations in stratigraphic architecture, approximated here by platform-margin trajectory. This relationship implies a significant stratigraphic control on syndepositional deformation in carbonate platforms and suggests that external drivers are not required to generate early fractures in high-relief carbonate platforms.
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Gold metallogeny of AustraliaRankine, Graham M January 1987 (has links)
The gold metallogeny of Australia is predominantly confined to the Archaean and Palaeozoic Provinces. The Archaean gold occurrences are predominantly hosted in ultramafic-mafic dominated greenstone belts, with less associated tofelsic-volcanic and sedimentary sequences. Most gold occurrences are confined to shear zones or faults, and adjacent discoveries of economic laterite-hosted deposits, host rocks. Recent are presently under investigation and will supply a significant proportion of production in the future. The Proterozoic gold deposits of Australia , are confined to geosyncinal sequences, commonly turbidites (eg: Telfer), with other hydrothermal deposits associated directly to granites. An important feature of the North Australian Craton deposits, is the spatial association of most deposits to granite bodies, although a genetic link has not been established conclusively. The Roxby Downs deposit in South Australia is a unique occurrence of gold in association to copper, uranium and R.E.E. This deposit is tentatively related to intraplate alkaline-magmatism, with further work necessary. The most significant recent discovery of gold mineralization in Australia is in the Drummond Basin in Queensland. This epithermal is tentatively related to mineralization within the Georgetown Inlier. The latter mineralization is Permo-Carboniferous, in a Proterozoic (and possibly Archaean) sequence of schists. It is tentatively suggested that all the gold mineralization in northern Queensland may be related to single tectonic event, a feature which requires further study . Other mineralization in the Phanerozoic includes the turbidite-hosted metamorphogenic deposits of Victoria, the rift related deposits in New South Wales and magmatic related deposits in Queensland. The gold deposits in Australia may in the future be classified in a tectonogeological framework, similiar to the layout of this dissertation, particularly once further data becomes available on recent discoveries.
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A comparison of the seismicity and regional geology of the southeastern United States and southeastern AustraliaHunter, Stephen Allen 24 September 2008 (has links)
The southeastern United States and southeastern Australia are both intraplate regions. They are characterized topographically and geologically by low relief, Paleozoic mountain belts that parallel continental margins formed by rifting. Interestingly, there are also remarkable similarities in the seismicity of the two areas.
To characterize the temporal aspects of seismicity, the recurrence relationship, log N (number of earthquakes per year) versus I<sub>o</sub> (maximum intensity), for southeastern Australia was determined to be:
log N = 3.28 - 0.61 I<sub>o</sub>; III ≤ I<sub>o</sub> ≤ VII
Comparison with a similar relationship for the southeastern United States,
log N = 3.01 - 0.59 I<sub>o</sub>; V ≤ I<sub>o</sub> ≤ VIII.
(Bollinger, G. A., 1973) indicates that both the level of seismic activity and the distribution of earthquakes by size are comparable in the two regions. Additionally, strain release studies for the two regions, while subject to considerable uncertainty, do support that similarity. Note that the intensity X, 1886 Charleston, South Carolina, earthquake was not included in either the recurrence or strain studies.
Comparison of the spatial patterns of earthquake epicenters in both regions reveals only weak correlations of the seismicity with topography or with regional geology. There is, however, no apparent correlation with major igneous outcrops or with most major through-going faults. Both regions have seismic zones that are transverse or parallel to the regional geologic trends or tectonic fabrics. The parallel zones are usually associated spatially with severely-faulted regions, suggesting a possible causal relationship. For southeastern Australia, such zones exhibit northeast-trending normal faults of Jurassic age while for the southeastern United States, there are northeast-trending Pennsylvanian-Permian thrust faults. However, no such fault concentrations are found in the transverse seismic zones. Thus, the severely-faulted Source region hypothesis does apply uniformly. Indeed, it may be that, in portions of both of these widely separated geographic regions, the seismic activity is associated with deep crustal features that have no obvious surface expression. / Master of Science
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Evaluation and application of the amino acid racemisation reaction in studies of quaternary coastal and marine sediments in Australia / by Colin Vincent Murray-WallaceMurray-Wallace, Colin Vincent January 1987 (has links)
Bibliography: leaves 275-290 / xviiii [i.e. xvix], 352 leaves : ill ; 31 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Geology and Geophysics, 1987
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Developing a tectonic framework for the Southern Curnamona Cu - Au Province : geochemical and radiogenic isotope applicationsRutherford, Lachlan Stuart January 2006 (has links)
"Two independent geochronological techniques specifically targeting post-kinematic or late-stage growth of kyanite, staurolite and late-stage garnet in the southern Curnamona Province has found that these minerals grew during the Delamerian Orogeny (~530-500 Ma). Prograde metamorphism during the Delamerian Orogeny attained kyanite-staurolite-garnet grade (amphibolite-facies). Previous interpretations of an anticlockwise P-T path for the Olarian Orogeny need revising, as these interpretations have been shown in this study to be based on textural relationships spanning ~1100 million years. This highlights the importance of in situ geochronological techniques in defining robust P-T-t paths for a region." --p. 121 of source document. / Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2006.
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Preliminary hydraulic characterization of a fractured schist aquifer at the Koongarra uranium deposit, Northern Territory, AustraliaNorris, James, 1953- January 1989 (has links)
The Koongarra uranium deposit is hosted by quartz-chlorite schists. A conceptual model for the hydrogeology of the deposit is proposed on the basis of lithologic criteria and limited hydraulic testing. Water-level and aquifer-test data are presented that indicate the deposit lies within a partially confined, heterogeneous, anisotropic fractured-rock aquifer. The aquifer is dynamic with annual, diurnal, and semidiurnal water-level fluctuations. The results of aquifer tests indicate a high degree of connectivity in the aquifer. Fracture-dominated flow is observed in some tests, but the overall aquifer response appears to be that of an equivalent porous medium. A homogeneous, anisotropic model is used to estimate the transmissivity tensor for subregions of the aquifer. Anisotropy is well-developed with north- to east-northeast-oriented principal transmissivities. Northeast directions represent large-scale drawdown patterns and are subparallel to bedrock structure and the Koongarra fault. Northerly directions are localized and may reflect a less extensive fracture fabric or a flexure in the bedrock foliation.
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