Accessory Mineral Microstructure and Implications for Geochronology. U-Pb geochronology of accessory minerals is widely used to constrain the timing of igneous, metamorphic and sedimentary processes. However, our current knowledge of isotope mobility in these important minerals cannot readily explain some common features of U-Pb dating. Using new developments in quantitative microstructural analysis integrated with high spatial resolution geochronology we will constrain the relationship between ....Accessory Mineral Microstructure and Implications for Geochronology. U-Pb geochronology of accessory minerals is widely used to constrain the timing of igneous, metamorphic and sedimentary processes. However, our current knowledge of isotope mobility in these important minerals cannot readily explain some common features of U-Pb dating. Using new developments in quantitative microstructural analysis integrated with high spatial resolution geochronology we will constrain the relationship between accessory minerals deformation and its effect on radiometric ages. Our results will lead to a better understanding of geochemical modification of accessory minerals and may lead to the development of new applications of geochronology and improve the dating of rock deformation.Read moreRead less
Evolution of a two billion year subduction zone: Insights from the integration of microstructure and geochronology. The dynamic evolution of the earth is fundamentally linked to its thermal history. Since, the internal heat production of the earth has changed over time, plate tectonic processes may also have changed over earth history. The manner and timing of this change is highly controversial. We aim to address the nature of tectonic processes 2 billion years ago by studying one of the wor ....Evolution of a two billion year subduction zone: Insights from the integration of microstructure and geochronology. The dynamic evolution of the earth is fundamentally linked to its thermal history. Since, the internal heat production of the earth has changed over time, plate tectonic processes may also have changed over earth history. The manner and timing of this change is highly controversial. We aim to address the nature of tectonic processes 2 billion years ago by studying one of the world's oldest subduction zones (the Usagarian belt in Tanzania). The geometry, kinematics and deformation history of the subduction complex will be integrated with radiometric age dating to quantify the style and rates of ancient tectonic processes.Read moreRead less
The ins and outs of a Proterozoic supercontinent - what is the significance of 990-900 Ma orogenesis for the assembly of Rodinia? The hypothesis that all of Earth's continents came together one billion years ago to form a supercontinent known as Rodinia has invigorated debate about ancient continental distributions. Current models depict a flawed configuration for Rodinia, since they assume that continental fragments preserving evidence for quite different episodes of tectonic activity between ....The ins and outs of a Proterozoic supercontinent - what is the significance of 990-900 Ma orogenesis for the assembly of Rodinia? The hypothesis that all of Earth's continents came together one billion years ago to form a supercontinent known as Rodinia has invigorated debate about ancient continental distributions. Current models depict a flawed configuration for Rodinia, since they assume that continental fragments preserving evidence for quite different episodes of tectonic activity between 1350 and 900 million years ago developed at the same time. This project will make new correlations based upon careful observation and precise isotopic dating of rocks in Antarctica and Mexico, and will use these data to develop a more realistic picture of the ancient Earth.Read moreRead less
Crustal-Scale Fluid Flow in Deep Intracontinental Settings: Conditions, Sources and Deformational Responses. Fluids are important agents of heat and mass transport in the Earth's crust. They play a key role in the mobilisation of metals and as such play a crucial role in the generation of ore deposits. The outcomes of this project will result in a greater understanding of the mechanisms and sources of fluid generation and mobilisation in deep-crustal settings. These outcomes can be related direc ....Crustal-Scale Fluid Flow in Deep Intracontinental Settings: Conditions, Sources and Deformational Responses. Fluids are important agents of heat and mass transport in the Earth's crust. They play a key role in the mobilisation of metals and as such play a crucial role in the generation of ore deposits. The outcomes of this project will result in a greater understanding of the mechanisms and sources of fluid generation and mobilisation in deep-crustal settings. These outcomes can be related directly to the understanding of the controls on the transport and deposition of metals and hence the formation of mineral resources which are vital to maintaining a strong Australian economy.Read moreRead less
MACQUARIE ISLAND: A UNIQUE WINDOW INTO THE OCEAN BASEMENT AND THE LINK BETWEEN OCEAN RIDGES AND OPHIOLITES. Knowledge about the composition and structure of the oceanic crust is limited due to the inaccessibility of the deep-ocean floor. Macquarie Island is the only fragment of ocean crust and mantle exposed above sea-level in the world, providing a unique opportunity to study processes of oceanic floor generation in-situ. Our project will carry out detailed mapping of the lower crust and mantle ....MACQUARIE ISLAND: A UNIQUE WINDOW INTO THE OCEAN BASEMENT AND THE LINK BETWEEN OCEAN RIDGES AND OPHIOLITES. Knowledge about the composition and structure of the oceanic crust is limited due to the inaccessibility of the deep-ocean floor. Macquarie Island is the only fragment of ocean crust and mantle exposed above sea-level in the world, providing a unique opportunity to study processes of oceanic floor generation in-situ. Our project will carry out detailed mapping of the lower crust and mantle sections on the island, followed by an integrated microstructural, petrological, and geochronological analysis of samples. Such investigations may lead to fundamental advances in the understanding of formation, deformation, and emplacement of oceanic crust at mid-ocean ridge spreading centres.Read moreRead less
Driving Mechanisms of Mountain Building in Accretionary Orogens. Accretionary mountain belts constitute major portions of the Earth's continental crust including the Yilgarn in Western Australia and the area east of Broken Hill constituting a third of the Australian land mass. Understanding the origin of the Permo-Triassic (300-230 Ma) mountain range that lay along the margin of Gondwana from Eastern Australia to South America will provide a new insight into our environment and stimulate interna ....Driving Mechanisms of Mountain Building in Accretionary Orogens. Accretionary mountain belts constitute major portions of the Earth's continental crust including the Yilgarn in Western Australia and the area east of Broken Hill constituting a third of the Australian land mass. Understanding the origin of the Permo-Triassic (300-230 Ma) mountain range that lay along the margin of Gondwana from Eastern Australia to South America will provide a new insight into our environment and stimulate international interest through collaboration amongst researchers around the world. Accretionary orogens are of economic importance as they host the Earth's major orogenic gold deposits and our work has potential to provide a new framework for linking mineralization and deformation events within these important settings.Read moreRead less
Tectonic evolution and lode gold mineralisation in the Southern Cross district, Yilgarn Craton (Western Australia): a study of the meso- to Neoarchaean missing link. In the December quarter 2008, Gold export earnings increased by 2 per cent to $3.9 billion. Over the past 20 years and despite an increase in exploration expenditure to around $50 million per year, the discovery rates have been declining. Although the easy targets have been found, there remains considerable potential for future ma ....Tectonic evolution and lode gold mineralisation in the Southern Cross district, Yilgarn Craton (Western Australia): a study of the meso- to Neoarchaean missing link. In the December quarter 2008, Gold export earnings increased by 2 per cent to $3.9 billion. Over the past 20 years and despite an increase in exploration expenditure to around $50 million per year, the discovery rates have been declining. Although the easy targets have been found, there remains considerable potential for future major discoveries. This project addresses the pressing need for new data and improved exploration techniques to enable industry to target new discoveries. As the Southern Cross district is located in remote communities such discoveries also have major benefits for regional Australia.Read moreRead less
Defects and Deformation in Olivine: From Molecules to Mantle. This project establishes the role of hydrogen in controlling olivine deformation, plate tectonics and mantle geodynamics. The unique application of innovative nanoscale simulation, microscale observation and geophysical characterisation ensures that results will have far-reaching impact in the Australian and International Earth Science community. In particular, our results will enable greater understanding of water migration in the m ....Defects and Deformation in Olivine: From Molecules to Mantle. This project establishes the role of hydrogen in controlling olivine deformation, plate tectonics and mantle geodynamics. The unique application of innovative nanoscale simulation, microscale observation and geophysical characterisation ensures that results will have far-reaching impact in the Australian and International Earth Science community. In particular, our results will enable greater understanding of water migration in the mantle, the formation of deep Earth mineral resources and lead to significant improvements in the interpretation of geophysical variations in Earth's lithosphere.Read moreRead less
The Effects of Crystal-Plastic Deformation on Zircon Geochemical Systems. This project establishes the significance of deformation-related fast-diffusion pathways on the zircon geochemical system and develops intragrain compositional variations as new tools for tracking geological processes. The unique application of zircon to constrain geological processes in numerous Earth Science disciplines over 4.4 billion years of Earth history ensures that results will have far-reaching impact in the Aust ....The Effects of Crystal-Plastic Deformation on Zircon Geochemical Systems. This project establishes the significance of deformation-related fast-diffusion pathways on the zircon geochemical system and develops intragrain compositional variations as new tools for tracking geological processes. The unique application of zircon to constrain geological processes in numerous Earth Science disciplines over 4.4 billion years of Earth history ensures that results will have far-reaching impact in the Australian and International Earth Science community. As such this project will maintain Australia's leading international reputation in accessory mineral research.Read moreRead less
A virtual exploration of iron-sulphur-world in search of the precursors to life on earth. The greenhouse gas, carbon dioxide, that currently presents a threat to the continued existence of humanity, ironically represents the starting point from which life on Earth probably originated. This research will probe the chemistry of how this gas, dissolved in ancient oceans, came to be converted to molecules that form the basis of living organisms through interaction with minerals, such as iron sulphid ....A virtual exploration of iron-sulphur-world in search of the precursors to life on earth. The greenhouse gas, carbon dioxide, that currently presents a threat to the continued existence of humanity, ironically represents the starting point from which life on Earth probably originated. This research will probe the chemistry of how this gas, dissolved in ancient oceans, came to be converted to molecules that form the basis of living organisms through interaction with minerals, such as iron sulphide. Aside from answering a fundamental question, it will offer insights into processes that convert a pollutant into a useful chemical, as well as what might happen if carbon dioxide is placed in mineral deposits for long-term storage.Read moreRead less