The Earth's Deep Carbon Cycle. The climate change debate has focused scientific attention on Earth’s exogene carbon-cycle. However, Earth has another, much deeper carbon-cycle which is poorly understood. In addition to exerting a profound influence on atmospheric greenhouse gas concentrations over time scales from thousands to billions of years, it is critically important in many processes in the Earth’s deep mantle. The major means by which the deep carbon-cycle is replenished is via subduction ....The Earth's Deep Carbon Cycle. The climate change debate has focused scientific attention on Earth’s exogene carbon-cycle. However, Earth has another, much deeper carbon-cycle which is poorly understood. In addition to exerting a profound influence on atmospheric greenhouse gas concentrations over time scales from thousands to billions of years, it is critically important in many processes in the Earth’s deep mantle. The major means by which the deep carbon-cycle is replenished is via subduction of carbonate-bearing oceanic crust. The project proposes a high-pressure experimental and field-based program to understand the fate of this carbonate during its journey from the exosphere, through subduction zones and into the deep mantle.Read moreRead less
Continents in the Mantle Transition Zone? Sediment Recycling and the Geochemical Fertilization of the Deep Mantle. Because of its intrinsic compositional buoyancy, continental crust has traditionally been considered to be unsubductable in the denser underlying mantle. Yet some ocean island basalts carry a geochemical signature of recycled continental material in their plume source in the deep mantle. This project will reconcile this paradox through high-pressure experiments that will simulate su ....Continents in the Mantle Transition Zone? Sediment Recycling and the Geochemical Fertilization of the Deep Mantle. Because of its intrinsic compositional buoyancy, continental crust has traditionally been considered to be unsubductable in the denser underlying mantle. Yet some ocean island basalts carry a geochemical signature of recycled continental material in their plume source in the deep mantle. This project will reconcile this paradox through high-pressure experiments that will simulate subduction of continental sediments into the deep mantle. These experiments will provide the first empirical constraints on the role of sediment-derived fluids in mantle metasomatism and the origin of economically-rich potassic magmas, and the nature of the ultrarefractory continental component that ultimately reaches the plume source for ocean-island basalts.Read moreRead less
Resolving the influence of intraplate orogenesis on continental margin tectonics. Novel, multi-dating of continental sedimentary rocks will be undertaken to examine the effects of a high sediment flux from an enigmatic, major mountain-building event on a distant continental margin. This will expand our understanding of the range of tectonic influences between continental interiors and margins and onshore resource potential.
Down under down under: using multi-scale seismic tomography to image beneath Australia's Great Artesian Basin. Seismic arrays will be deployed in the Great Artesian Basin to image the crust and mantle using distant earthquake and ambient noise sources. This will answer fundamental questions about the tectonic evolution of eastern Australia and elucidate the structure of a region containing significant deep Earth resources.
Magnetite and metal-rich sulphides in arc magmas. Ascending magmas cool and crystallise a variety of minerals. Triggering sulfide deposition which hosts base and precious metals is a critical point in magma evolution. This research will explore the role of magnetite as this trigger and its potential as a tracer of this process.
The link between cratonic roots, redox state, and mantle geodynamics. This project aims to understand the role of Earth's redox state on the geodynamic evolution of continental cratonic roots. Cratonic roots form strong, buoyant rafts upon which Australia's oldest crust and mineral deposits survived. Cratons preserve a record of planetary-scale chemical shifts, including the rise of surface oxygen, but it is unclear how these redox shifts themselves affected lithospheric processes. This project ....The link between cratonic roots, redox state, and mantle geodynamics. This project aims to understand the role of Earth's redox state on the geodynamic evolution of continental cratonic roots. Cratonic roots form strong, buoyant rafts upon which Australia's oldest crust and mineral deposits survived. Cratons preserve a record of planetary-scale chemical shifts, including the rise of surface oxygen, but it is unclear how these redox shifts themselves affected lithospheric processes. This project integrates new developments in geochemistry, geophysics, and geodynamics, to map the geochemical state and structure of cratonic roots, aiding mineral exploration, and also shedding light on the processes that modify, mineralise, and sometimes destroy cratonic roots.Read moreRead less
Magma dynamics and ore deposits. This project aims to advance knowledge on magma transport mechanisms through the Earth’s lithosphere, and boost predictive capacity to discover new ore deposits. Using field surveys, three-dimensional reflection seismic data, laboratory experiments and rock fracture mechanics, this project will investigate where, how and why, narrow finger-like conduits form in lithosphere-scale magma plumbing systems. The project expects to generate new knowledge on the formatio ....Magma dynamics and ore deposits. This project aims to advance knowledge on magma transport mechanisms through the Earth’s lithosphere, and boost predictive capacity to discover new ore deposits. Using field surveys, three-dimensional reflection seismic data, laboratory experiments and rock fracture mechanics, this project will investigate where, how and why, narrow finger-like conduits form in lithosphere-scale magma plumbing systems. The project expects to generate new knowledge on the formation and location of highly valuable ore deposits of nickel, copper, cobalt and platinum group elements, which are preferentially trapped in poorly understood, finger-like magma conduits. Anticipated outcomes of the project include fundamental insights into how magma transport dynamics control traps for magmatic sulfide ores as well as equipping mineral explorers in targeting their search for these important, but hard to find, ore deposits, benefitting society through future discoveries of economically strategic, new commodities.Read moreRead less
Seeing the unseeable: A new generation of geophysical imaging. This project aims to develop novel mathematical frameworks for probabilistic geophysical imaging and inference, building on recent advances in statistics and machine learning. These will allow us to obtain a more detailed and robust understanding of structures and processes occurring within the Earth, including those relevant to the Australian minerals and/or energy industries. Outcomes of this research include mathematical and compu ....Seeing the unseeable: A new generation of geophysical imaging. This project aims to develop novel mathematical frameworks for probabilistic geophysical imaging and inference, building on recent advances in statistics and machine learning. These will allow us to obtain a more detailed and robust understanding of structures and processes occurring within the Earth, including those relevant to the Australian minerals and/or energy industries. Outcomes of this research include mathematical and computational tools for imaging the subsurface, and greater understanding of Australian and global geoscience. This work can permit more effective exploitation of earth resources, as well as improving our understanding of how the Earth system has developed over geological history. 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
Mapping mineral systems of deep Australia. We aim at enabling mineral resource discoveries by calibrating geophysical surveys using geochemical and petrophysical properties measured on mantle samples brought to the surface by recent volcanoes. National geophysical surveys deliver images of geophysical gradients in the deeper part of the Australian continent. The interpretation of these gradients in geological terms and in terms of economic mineral systems is the key to unlock deep exploration su ....Mapping mineral systems of deep Australia. We aim at enabling mineral resource discoveries by calibrating geophysical surveys using geochemical and petrophysical properties measured on mantle samples brought to the surface by recent volcanoes. National geophysical surveys deliver images of geophysical gradients in the deeper part of the Australian continent. The interpretation of these gradients in geological terms and in terms of economic mineral systems is the key to unlock deep exploration success. This project will turn Australia’s investment in National geophysical surveys into new discoveries of base metals. The benefit stems from enabling the transition to a clean economy which requires a much broader range of critical minerals and a larger quantity of base metals.Read moreRead less