Tracking mass transport during metamorphism using in situ micro-analysis of minerals. The continental masses we inhabit developed in response to the colossal forces of plate tectonics. Through compression and heating, rocks of the crust can experience fluid loss or melting. Movement of these fluids or magmas can, among other things, impact on the heat budget of Earth, the carbon and water cycles and the formation of ores in the crust. This project will utilize state-of-the-art scientific instrum ....Tracking mass transport during metamorphism using in situ micro-analysis of minerals. The continental masses we inhabit developed in response to the colossal forces of plate tectonics. Through compression and heating, rocks of the crust can experience fluid loss or melting. Movement of these fluids or magmas can, among other things, impact on the heat budget of Earth, the carbon and water cycles and the formation of ores in the crust. This project will utilize state-of-the-art scientific instruments and methods to greatly improve our understanding of these issues, which, in turn, will enhance our knowledge of how the Earth's crust develops. Research training and development will be provided through two PhD projects supported through this project.Read moreRead less
An experimental study of trace element equilibria during metamorphism. The analytical methods and experimental data to be developed will enable an Australian team to become world leaders in determining pressures and temperatures of mineral growth that correspond to a range of depths and temperature gradients in the Earth tha t is wider than accessible previously. Obtaining this information from small zones within single grains will allow determination of rates of change, and give us a detailed p ....An experimental study of trace element equilibria during metamorphism. The analytical methods and experimental data to be developed will enable an Australian team to become world leaders in determining pressures and temperatures of mineral growth that correspond to a range of depths and temperature gradients in the Earth tha t is wider than accessible previously. Obtaining this information from small zones within single grains will allow determination of rates of change, and give us a detailed picture of how the host rock has evolved, even from very small samples. One application would be checking the origin of relatively common minerals for whether they could be associated with diamonds.Read moreRead less
Order-disorder behaviour in Bi-tellurides: a tool to monitor gold scavenging by Bi-Te melts. This project addresses a group of minerals (bismuth tellurides) that are often part of the exotic assemblages present in gold deposits, yet their potential to model the gold-forming processes is only recently apparent. These minerals also have the capacity to record their genetic history due to crystal modularity. Materials scientists target the analogous synthetic compounds because of the same structura ....Order-disorder behaviour in Bi-tellurides: a tool to monitor gold scavenging by Bi-Te melts. This project addresses a group of minerals (bismuth tellurides) that are often part of the exotic assemblages present in gold deposits, yet their potential to model the gold-forming processes is only recently apparent. These minerals also have the capacity to record their genetic history due to crystal modularity. Materials scientists target the analogous synthetic compounds because of the same structural modularity for applications in nanotechnology. The dataset on the mineral compounds, using the geological environment as a natural laboratory, will serve materials science research, as much as delivering key information relevant to understanding the reasons for gold enrichment in economically important types of ores. Read moreRead less
Experimental studies on hydrothermal reaction processes at the molecular level: the role of mineral replacement reactions in ore formation. Most of the World's supply of metals such as copper (Cu), gold (Au), molybdenum (Mo), lead (Pb), zinc (Zn) or uranium (U) comes from hydrothermal ore deposits. The metals were deposited deep below the Earth's surface when hot fluids, carrying minute quantities of the metals, reacted with suitable rocks to form ore minerals. By understanding molecular-level ....Experimental studies on hydrothermal reaction processes at the molecular level: the role of mineral replacement reactions in ore formation. Most of the World's supply of metals such as copper (Cu), gold (Au), molybdenum (Mo), lead (Pb), zinc (Zn) or uranium (U) comes from hydrothermal ore deposits. The metals were deposited deep below the Earth's surface when hot fluids, carrying minute quantities of the metals, reacted with suitable rocks to form ore minerals. By understanding molecular-level reaction mechanisms at high pressure and temperature, we can predict the nature of the ore minerals formed for a given set of physical and chemical conditions. This multidisciplinary research project is devoted to understanding these chemical and physical processes and how this knowledge can be applied to improve mineral exploration, mining, and ore processing.Read moreRead less
The role of melting of oceanic crust within the subduction factory: A melt inclusion approach. Continental crust is ultimately generated in subduction zones, where oceanic crust is recycled back into the mantle along deep ocean trenches, producing island arcs. Processes occurring in the subduction 'factory' are poorly understood, but dehydration of old subducted oceanic crust is usually invoked to provide water that triggers mantle melting and arc magmatism. Evidence is accumulating that in many ....The role of melting of oceanic crust within the subduction factory: A melt inclusion approach. Continental crust is ultimately generated in subduction zones, where oceanic crust is recycled back into the mantle along deep ocean trenches, producing island arcs. Processes occurring in the subduction 'factory' are poorly understood, but dehydration of old subducted oceanic crust is usually invoked to provide water that triggers mantle melting and arc magmatism. Evidence is accumulating that in many locations the subducted oceanic crust may melt, rather than simply dehydrate. I will test this using studies of melt inclusions (droplets of melt trapped by crystals growing in the magma), and will better constrain the input-output budgets of the subduction factory.Read moreRead less
Dynamic permeability and the evolution of fluid pathways in fracture-controlled hydrothermal systems. This project will advance knowledge of how fracture-controlled fluid flow at depth in the Earth influences the strength and mechanical behaviour of the crust, earthquake processes, and the formation of hydrothermal ore systems. Fundamental new knowledge of the dynamic variations in fluid transport properties and flow distribution in deep fracture networks also will have application for understan ....Dynamic permeability and the evolution of fluid pathways in fracture-controlled hydrothermal systems. This project will advance knowledge of how fracture-controlled fluid flow at depth in the Earth influences the strength and mechanical behaviour of the crust, earthquake processes, and the formation of hydrothermal ore systems. Fundamental new knowledge of the dynamic variations in fluid transport properties and flow distribution in deep fracture networks also will have application for understanding hydrocarbon migration in fractured reservoirs, controls on seal integrity in geosequestration projects, and for geothermal energy production from hot, fractured rock. The project will develop international collaboration and train young scientists in applying multidisciplinary approaches to exploring fluid systems in the Earth's crust.Read moreRead less
Phosphate stabilisation of metalliferous mine wastes: The key to solving a major environmental issue? Mine wastes represent the greatest proportion of solid waste produced by mankind. Unconstrained drainage from sulfide-rich mine wastes impacts on water, soil and sediment quality. This project will establish the scientific principles of phosphate stabilisation, which involves the addition of phosphate compounds to mine wastes and soils to permanently contain metals and acid. A solid understandin ....Phosphate stabilisation of metalliferous mine wastes: The key to solving a major environmental issue? Mine wastes represent the greatest proportion of solid waste produced by mankind. Unconstrained drainage from sulfide-rich mine wastes impacts on water, soil and sediment quality. This project will establish the scientific principles of phosphate stabilisation, which involves the addition of phosphate compounds to mine wastes and soils to permanently contain metals and acid. A solid understanding of this emerging technology is a prerequisite for any sustainable management of mine sites. The study will provide the foundation of future management tools needed by landholders, industry and regulators to remediate mined land and waste repositories.Read moreRead less
Experimental and natural constraints on trace element and volatile recycling in subduction zones. The results of this project will provide important constraints on the differentiation of Earth, which ultimately leads to the concentration of elements suitable for mining. Trace element and volatile recycling in subduction zones is an integral part of the research theme 'Journey to the centre of the Earth' which has been identified as a key project (4.4) in the national strategic plan for geoscienc ....Experimental and natural constraints on trace element and volatile recycling in subduction zones. The results of this project will provide important constraints on the differentiation of Earth, which ultimately leads to the concentration of elements suitable for mining. Trace element and volatile recycling in subduction zones is an integral part of the research theme 'Journey to the centre of the Earth' which has been identified as a key project (4.4) in the national strategic plan for geosciences. CO2 recycling in subduction zones is crucial for our understanding of the long-term greenhouse gas variations on Earth. The ANU is one of the world-leading research institutions in experimental petrology and geochemistry, and the outcomes of this project will ensure that Australia remains at the forefront in these disciplines.Read moreRead less
Properties of hydrous fluids and silicate melts at very high temperatures and pressures. High-temperature, high-pressure, water-rich fluids play a central role in many geological processes. However, these fluids are extremely difficult to characterise: although their effects are evident in many rocks, the fluids themselves are too reactive to be preserved. Here several novel techniques are described for studying the compositions and thermodynamic properties of hydrous fluids and silicate melts o ....Properties of hydrous fluids and silicate melts at very high temperatures and pressures. High-temperature, high-pressure, water-rich fluids play a central role in many geological processes. However, these fluids are extremely difficult to characterise: although their effects are evident in many rocks, the fluids themselves are too reactive to be preserved. Here several novel techniques are described for studying the compositions and thermodynamic properties of hydrous fluids and silicate melts over a wide range of geologically relevant conditions. The results of this study will greatly improve the understanding of geological processes as widely diverse as volcanism, ore deposition and metamorphism.Read moreRead less
CO2-brine behaviour in high temperature geological processes: Microanalysis and significance. This project clearly lies within the national research priority of developing deep earth resources. It may strengthen our economic fabric through mineral deposit discoveries in Australia as well as other circum-Pacific countries. The proposed research will also indirectly enhance our understanding of the relationships between geosphere, biosphere, fluids and global greenhouse warming. By strong national ....CO2-brine behaviour in high temperature geological processes: Microanalysis and significance. This project clearly lies within the national research priority of developing deep earth resources. It may strengthen our economic fabric through mineral deposit discoveries in Australia as well as other circum-Pacific countries. The proposed research will also indirectly enhance our understanding of the relationships between geosphere, biosphere, fluids and global greenhouse warming. By strong national and international collaborations and our use of innovative frontier technologies of fluid microgeochemistry, we will expand recognition of Australia's world-class research capacities.Read moreRead less