Science Collected Works - Theses

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    The sedimentary and tectonic structures of the Lower Devonian Liptrap formation, Victoria, Australia
    O'Connor, Bernard (University of Melbourne, 1978)
    The shore-platform and cliff exposures of the (Lower Devonian) Liptrap Formation were mapped around Cape Liptrap. In all, 3200 metres of interbedded sandstones and mudstones together with occasional slump beds were examined and the tectonic and sedimentary structures contained within them described in detail. In addition, the overall sedimentary and tectonic environments are discussed. The sediments were derived from two sources; a more distant provenance located on a granitic� metamorphic terrain in eastern Victoria and a local prevenance across the Waratah Fault located in Cambrian greenstones and Devonian sediments. The direction of overfolding of slumped beds indicates a palaeoslope from east to west, while current direction indicators show movement from the east. The sequence of sedimentary structures developed within sandstone-mudstone couples indicates emplacement of the sediments chiefly by bottom traction. Rapid deposition is suggested by structures indicating post-depositional instability with a variety of water-escape structures being developed. The overall sedimentary environment is interpreted as being that of a small-scale shallow water submarine fan deposit. Tectonic structures were developed under a low cover during a single phase of folding and regional cleavage formation - the Middle Devonian Tabberabberan deformation. Chevron folds plunge at low angles to the.north or south, while minor parasitic folds have a different but predictable orientation relative to major fold axes in that they diverge from the major anticlinal axes and converge on the synclines. This is caused by local reorientation of the overall stress field on the limbs of the major folds which have an initial plunge. Folds show evidence for generation at and migration from point sources with consequent rapid changes in plunge both between different folds and within individual folds. In the profile plane a cyclical change in fold form can be seen with single hinged chevron folds giving way to box folds which have two diverging hinges. These style changes are thought to reflect packing difficulties encountered during tightening of the folds. The regional cleavage is statistically axial planar to the folds and is developed as a penetrative differentiated layering best seen in the mudstones. Mica rich M foliae and quartz rich Q zones indicate pressure solution of the more soluble minerals (chiefly quartz) with concentration of less soluble minerals (chiefly mica) at the solution surfaces. Mechanical rotation and deformation of larger clastic flakes attended the shortening which accompanied this pressure solution process. The geometrical and spatial relationship between certain post-depositional soft sediment structures and certain hard rock tectonic structures is noted and a possible link between tectonic and sedimentary structures is suggested, in that they may have developed at the same time.
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    Household vulnerabiltiy to climate change in a rural Chinese country : does the local state matter?
    Rogers, Sarah May (University of Melbourne, 2014)
    The aim of this thesis is to understand the vulnerability of rural households to climate change in China and the influence of local government on that vulnerability. To achieve this aim, two research questions are addressed: 1) in what ways are rural households vulnerable to climate change?; and 2) in what ways does local government influence rural household vulnerability to climate change? The thesis applies a sustainable livelihoods approach to examining household vulnerability and is further informed by theories of vulnerability to climate change and theories of central-local government relations in China. It posits that local governments influence the vulnerability of rural households by mediating their access to livelihood assets and activities, and by shaping their coping and adaptive strategies. The research questions are addressed through the analysis of data collected in four apple-producing villages � two wealthier and two poorer � in a case study county called Jixian. Jixian is a nationally designated poverty county that lies on the Loess Plateau in Shanxi Province. The methods used are primarily qualitative: semi-structured interviews and direct observation, supported by secondary data collection. The thesis finds that all households in all villages are vulnerable to climate change due to water insecurity, but that some are more vulnerable than others as a result of differential access to land. Households in wealthier villages have better access to land such that they are better able to cope with climatic stress than households in poorer villages. In relation to local government influence, it is the county government that has the most influence through its allocation of resources to villages. Resource allocation is done in such a way as to favour the two wealthier, more developed villages, thus amplifying existing differences in access to resources between villages. Yet the county government�s influence on vulnerability is far from absolute, as the major drivers of household vulnerability in Jixian, which are access to land and water, lie beyond its control.
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    Structural evolution and hydrocarbon play fairways of the Gippsland basin
    Power, Michael Roderic. (University of Melbourne, 2003)
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    Severe weather forecasting in coastal East Antarctica
    Murphy, Bradley F. (University of Melbourne, 1999)
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    The chemistry of the ethylene sulphides and some related topics
    Culvenor, C. C. J (University of Melbourne, 1948)
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    Geological investigations in the Murray Basin in New South Wales
    Pels, Simon. (University of Melbourne, 1962)
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    Bonding and anharmonic vibration in some high symmetry crystals
    Moss, Grant Richard. (University of Melbourne, 1977)
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