Rich Cousin, Poor Cousin - What Controls the Formation and Size of Orogenic Gold Deposits? What are the geological and geochemical factors that control the formation and size of gold deposits in Phanerozoic mountain belts (?orogens?)? The answer to this question lies in a combination of methods we will use to establish the importance of source, absolute timing of mineralisation, genetic links to magmas, and geochemical processes that result in the transport, and deposition of gold in three separ ....Rich Cousin, Poor Cousin - What Controls the Formation and Size of Orogenic Gold Deposits? What are the geological and geochemical factors that control the formation and size of gold deposits in Phanerozoic mountain belts (?orogens?)? The answer to this question lies in a combination of methods we will use to establish the importance of source, absolute timing of mineralisation, genetic links to magmas, and geochemical processes that result in the transport, and deposition of gold in three separate, geologically young orogens. The wider implications of this research include a greatly improved understanding of lesser known Phanerozoic orogenic gold provinces, ore genesis at convergent plate margins, and the formation of gold deposits in older terrains.Read moreRead less
Resolving the mystery of how rare earth elements are mobilised and concentrated in continental crust. Rare earth elements are regarded as the vitamins for modern industries and technologies. This project will investigate the geological processes that mobilise and concentrate these elements in the Earth's crust. The results will aid discovery of new ore deposits, which is essential to meet rapidly growing demand for these elements.
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
The copper-gold fertility of mountain belts. This project aims to identify the timing of, and understand the causes of, sulphide saturation in granitic suites to test the hypothesis that sulphide saturation controls the fertility of copper-gold deposits. More than half of the world’s copper and gold comes from granitic rocks, but most granitic suites are barren. As copper-gold deposits become increasingly difficult to find, and exploration budgets have been slashed, it is critical to reliably di ....The copper-gold fertility of mountain belts. This project aims to identify the timing of, and understand the causes of, sulphide saturation in granitic suites to test the hypothesis that sulphide saturation controls the fertility of copper-gold deposits. More than half of the world’s copper and gold comes from granitic rocks, but most granitic suites are barren. As copper-gold deposits become increasingly difficult to find, and exploration budgets have been slashed, it is critical to reliably distinguish ore bearing from barren systems. Platinum group element geochemistry could make this distinction by pinpointing the timing of sulphide saturation in evolving magma systems. Eliminating barren suites as exploration targets will save Australia’s exploration dollars which can be directed to where the prospects of success are greatest.Read moreRead less
Nature's mechanisms for leaching and remobilising metals. This project aims to understand the chemical and physical processes that govern reactive transport and metal scavenging in rocky environments. Much of Australia's mineral wealth is the result of the interaction of warm fluids with rocks deep in the Earth over geological timescales. The formation of ore deposits is governed by the physical chemistry of mineral dissolution and crystallisation, and by fluid flow through porous rocks and frac ....Nature's mechanisms for leaching and remobilising metals. This project aims to understand the chemical and physical processes that govern reactive transport and metal scavenging in rocky environments. Much of Australia's mineral wealth is the result of the interaction of warm fluids with rocks deep in the Earth over geological timescales. The formation of ore deposits is governed by the physical chemistry of mineral dissolution and crystallisation, and by fluid flow through porous rocks and fractures. This project integrates innovation in geology, chemistry, and mineral engineering, and will deliver mineral-scale reaction models that will increase efficiency of in-situ mining and leaching technologies. Knowledge generated can be applied to improve mineral exploration, mining, and processing, contributing to unlocking billions of dollars’ worth of resources tied up in low grade, mineralogically complex ores.Read moreRead less
Experiments to quantify the geochemical behaviour of the precious metals. This project aims to measure the high-temperature geochemical properties of the precious metals, which include gold, silver and the platinum group elements. The measurements are needed to quantify the partitioning of the precious metals between silicate melts and metal or sulfide, which would enable their distinctive geochemical properties to be applied to the testing of current hypotheses on how Earth formed, the composit ....Experiments to quantify the geochemical behaviour of the precious metals. This project aims to measure the high-temperature geochemical properties of the precious metals, which include gold, silver and the platinum group elements. The measurements are needed to quantify the partitioning of the precious metals between silicate melts and metal or sulfide, which would enable their distinctive geochemical properties to be applied to the testing of current hypotheses on how Earth formed, the composition of Earth's mantle through time, the relationship of Earth to the Moon, and the evolution of magmatic systems to form copper-gold deposits. The measurements have become feasible due to newly developed experimental and analytical methods, which avoid the problems that have bedevilled previous attempts.Read moreRead less
Geological applications of synchrotron radiation: magmas, fluids, ores and minerals. This project will use the Australian synchrotron facility to study magmas and minerals to improve our understanding of the formation of ore-deposits and the evolution of the continents.
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
Defining the multi-scale controls on high-grade gold mineralisation. This project aims to improve our understanding of how extremely high-grade gold occurrences form in order to further our understanding of metal transport and accumulation within the Earth’s crust. This project will generate new knowledge in the area of gold geochemistry using novel experimental programs, interdisciplinary approaches and by utilising advanced technologies. Expected outcomes of this project include reducing the ....Defining the multi-scale controls on high-grade gold mineralisation. This project aims to improve our understanding of how extremely high-grade gold occurrences form in order to further our understanding of metal transport and accumulation within the Earth’s crust. This project will generate new knowledge in the area of gold geochemistry using novel experimental programs, interdisciplinary approaches and by utilising advanced technologies. Expected outcomes of this project include reducing the unpredictability of high-grade gold occurrences that impact both production and exploration strategies. This project should benefit the mineral industry partners by helping to discover high grade gold resources which is of great benefit to Australia.Read moreRead less
Gold transport in aqueous versus organic fluids: Experimental data for describing ore-forming systems. In many hydrothermal ore-forming systems, the ore is associated with inclusions of both aqueous brine and organic liquid (petroleum). The conventional theory is that the metals are dissolved and transported to the deposit by the brine, but some researchers suggest that petroleum may fill this role. This project proposes to conduct an experimental and field-based study on the chemical behaviour ....Gold transport in aqueous versus organic fluids: Experimental data for describing ore-forming systems. In many hydrothermal ore-forming systems, the ore is associated with inclusions of both aqueous brine and organic liquid (petroleum). The conventional theory is that the metals are dissolved and transported to the deposit by the brine, but some researchers suggest that petroleum may fill this role. This project proposes to conduct an experimental and field-based study on the chemical behaviour of gold in aqueous-organic and organic fluid systems, to determine which type of liquid is more important for gold mobilisation in a competitive situation. This study will provide much-needed data for more accurate modelling of ore systems, furthering our understanding and facilitating mineral exploration. Read moreRead less