The hydrothermal solubility of molybdenum: A LA-ICPMS study of synthetic and natural fluid inclusions. The solubility of molybdenum under magmatic-hydrothermal conditions is essentially unknown. This study will, for the first time, identify the fundamental controls on molybdenum solubility in porphyry systems. This information will provide geologists with basic information on the transport and deposition of this important ore metal. In an allied study, the ore metals; copper, gold and molybdenum ....The hydrothermal solubility of molybdenum: A LA-ICPMS study of synthetic and natural fluid inclusions. The solubility of molybdenum under magmatic-hydrothermal conditions is essentially unknown. This study will, for the first time, identify the fundamental controls on molybdenum solubility in porphyry systems. This information will provide geologists with basic information on the transport and deposition of this important ore metal. In an allied study, the ore metals; copper, gold and molybdenum, will be traced through the Kidston porphyry system, Queensland. This will clarify the processes that lead to ore deposition, which will ultimately allow geologists to more effectively explore for porphyry-type deposits, a major target for Australian mining companies in the Pacific region.Read moreRead less
An experimental exploration of silicate melt therrmodynamics. The chemical properties of magmas are the key to understanding igneous activity in the Earth, and hence the tectonic significance of magmatism, and the mineral resources resulting from past magmatism. The chemistry of magmas is also a determining factor in assessing the hazards associated with volcanic eruptions, including natural inputs into the atmosphere against which anthropogenic inputs causing climate change must be assessed. Th ....An experimental exploration of silicate melt therrmodynamics. The chemical properties of magmas are the key to understanding igneous activity in the Earth, and hence the tectonic significance of magmatism, and the mineral resources resulting from past magmatism. The chemistry of magmas is also a determining factor in assessing the hazards associated with volcanic eruptions, including natural inputs into the atmosphere against which anthropogenic inputs causing climate change must be assessed. This research program will measure experimentally the way different magma compositions affect the solubilites of important volatile and trace-element components in magmas, providing the much-needed fundamental data to model magmatic activity.Read moreRead less
The Geochemistry of the Platinum Group Elements, Copper, Rhenium and Gold in Granitic Rocks. Many of the World's largest copper and gold deposits derive their ore fluids from crystallizing granitic magmas. These elements, together with the platinum group elements, are sequestered by immiscible sulfide melts, which when they precipitate from a magma, control the subsequent evolution of these elements. The proposed study takes advantage of platinum's remarkable affinity for sulfides to identify ....The Geochemistry of the Platinum Group Elements, Copper, Rhenium and Gold in Granitic Rocks. Many of the World's largest copper and gold deposits derive their ore fluids from crystallizing granitic magmas. These elements, together with the platinum group elements, are sequestered by immiscible sulfide melts, which when they precipitate from a magma, control the subsequent evolution of these elements. The proposed study takes advantage of platinum's remarkable affinity for sulfides to identify onset of sulfide saturation and then monitor its effect on the subsequent evolution of copper and gold in the evolving magma. It is expected to provide new insights into chemistry of copper and gold in crystallizing granitic melts and explain why some granitic systems are ore bearing and other are not. 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
In-situ solubility and speciation studies in super-critical H2O-NaCl-CO2 mixtures using synchrotron radiation. Understanding the physics and chemistry of metals in hypersaline and supercritical solutions represents a major scientific challenge with wide-ranging applications in the fields of mineral processing, economic geology, or CO2 sequestration. The advent of very bright sources of x-rays (synchrotrons) and development of spectroscopic cells that can contain corrosives samples at high pressu ....In-situ solubility and speciation studies in super-critical H2O-NaCl-CO2 mixtures using synchrotron radiation. Understanding the physics and chemistry of metals in hypersaline and supercritical solutions represents a major scientific challenge with wide-ranging applications in the fields of mineral processing, economic geology, or CO2 sequestration. The advent of very bright sources of x-rays (synchrotrons) and development of spectroscopic cells that can contain corrosives samples at high pressure and temperature allow for the first time the in-situ observation of these solutions. This project creates strong link between Australian and French scientists. By sharing the know-how developed at the European Synchrotron Research Facility, we aim to create a world-class facility at the Australian Synchrotron that will open in Melbourne in 2007.Read moreRead less
Transport of metals in vapours and brines: new insights into the formation of the Earth's mineral deposits. Traditional models for the formation of hydrothermal ore deposits assume that aqueous fluids transported the metals. This view is challenged by new observations showing that gold and copper are preferentially enriched in vapours coexisting with salty aqueous fluids in some deposits. This project uses state-of-the-art techniques and develops new instruments to measure experimentally the par ....Transport of metals in vapours and brines: new insights into the formation of the Earth's mineral deposits. Traditional models for the formation of hydrothermal ore deposits assume that aqueous fluids transported the metals. This view is challenged by new observations showing that gold and copper are preferentially enriched in vapours coexisting with salty aqueous fluids in some deposits. This project uses state-of-the-art techniques and develops new instruments to measure experimentally the partitioning of metals between solid, fluid and vapour at temperatures typical for natural ore deposits (350-550C, pressures varying for vapour saturated to 1 kb). By improving our understanding of metal transport within the Earth's crust, these data will lead to improved models and technologies for exploring and processing base and precious metals.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
A microscopic and analytical study of extreme thermophile bacteria in simulated environments compared to organic matter in early Earth hydrothermal systems. The study will examine microbial cells and organic residues of cultured thermophilic archaea from simulated extreme environments in terms of temperature, pressure and mineral concentrations. These will be compared, applying observational and geochemical techniques to organic material in geologically earliest ecosystems. A novel approach will ....A microscopic and analytical study of extreme thermophile bacteria in simulated environments compared to organic matter in early Earth hydrothermal systems. The study will examine microbial cells and organic residues of cultured thermophilic archaea from simulated extreme environments in terms of temperature, pressure and mineral concentrations. These will be compared, applying observational and geochemical techniques to organic material in geologically earliest ecosystems. A novel approach will be adopted, of 'backtracking' changes occurring to cultured microbial cells towards their breakdown and disintegration (in contrast to the more common approach of simulating synthesis of organic compounds as a starting point towards structured functioning organisms), and their viability limits. The results of the study will be tested within the currently available theoretical models for the origin of life.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
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