Unravelling the geodynamics of eastern Australia during the Permian: the link between plate boundary bending and basin formation

G. Rosenbaum, S.A. Pisarevsky, C.R. Fielding, F. Speranza: Supported by ARC Discovery (commenced 2013)

Summary:  The Permian evolution of eastern Australia is poorly understood. It involved bending of the southern New England Orogen and simultaneous development of widespread sedimentary basins. This project will combine palaeomagnetic and structural investigations to unravel the palaeogeography and plate kinematics of eastern Australia during the Permian. We will generate a comprehensive database on palaeolatitudes, block rotations and magnetic fabric, and will link, for the first time, the process of oroclinal bending with the development of the east Australian rift system. Outcomes will elucidate the fundamental tectonic process of oroclinal bending and will fill a knowledge gap in our understanding of the evolution of the Australian continent.

What lies beneath: Unveiling the fine-scale 3D compositional and thermal structure of the subcontinental lithosphere and upper mantle

J.C. Afonso, Y. Yang, N. Rawlinson, A.G. Jones, J.A.D. Connolly, S. Lebedev: Supported by ARC Discovery (commenced 2012)

Summary:  Characterising the compositional and thermal structure of the lithosphere and upper mantle is one of the most important goals of Geoscience. Yet, a method capable of providing robust estimates of these two fields in 3D has still not been achieved. This limitation is the focus of this project, which will develop the first full 3D method that integrates multiple geophysical and petrological datasets. We will apply our methodology to image the fine-scale thermochemical structure of the lithosphere beneath Australia, South Africa, and western USA. This project will not only help us understand the evolution of continental lithosphere but its outcomes will be translatable into predictive exploration methods for Australia’s Deep Earth Resources.

Investigation of the early history of the Moon: implications for the understanding of evolution of Earth and Solar System

A. Nemchin, M.L. Grange: Supported by ARC Discovery (commenced 2012)

Summary:  The goal of the project is to characterise the chemistry and timing of processes that shaped the specific evolutionary path followed by the Moon during the early history of the Solar System. This is not only vital for evaluation of lunar history, but is also essential for a better understanding of early evolution of the Earth, where the record of the first 500 m.y. of history has been erased by the continuous activity of the planet. The project will test existing models of lunar evolution describing initial global differentiation, early plutonic magmatism, impact history and volcanic activity, shedding new light on the processes driving these major events on the Moon and determining the ability of these models to describe the early history of the Earth.

Investigating the fundamental link between deformation, fluids and the rates of reactions in minerals

S. Piazolo, N.R. Daczko, A. Putnis, M.W. Jessell: Supported by ARC Discovery (commenced 2012)

Summary:  In Earth’s crust and mantle, minerals are constantly undergoing chemical changes while simultaneously being deformed. In this project we use a novel combination of techniques in order to advance our understanding of how deformation influences these chemical changes.

Supercells and the supercontinent cycle

W.J. Collins, J.B. Murphy, E. Belousova, M. Hand: Supported by ARC Discovery (commenced 2012)

Summary:  Phanerozoic plate motions can be explained by westerly and northerly migration of continental blocks toward Laurentia during protracted (~500 Ma) northerly mantle flow, confined within a hemispheric supercell. The other supercell on Earth encompasses the oceanic Pacific realm, characterised by E-W mantle flow diverging from the East Pacific Rise. We aim to determine if similar supercells and mantle flow patterns existed during the Proterozoic, by characterising contrasting orogenic systems within different supercells through tectonostratigraphic review, isotopic fingerprinting using Lu-Hf isotopes in zircon, and by paleomagnetic analysis. This is a new holistic approach to solving Precambrian geodynamics and continental reconstructions.

Multiple vertical tectonic movements in a continental interior: consequences of flat-subduction and foundering of an oceanic plateau?

Z.X. Li, M. Danisik, Y. Xu: Supported by ARC Discovery (commenced 2011)

Summary:  This project will investigate how the subduction of particularly thick oceanic crust impacts on the landscape, climate, structure and composition of the adjacent continent. It will help in understanding the history and distribution of mineral and hydrocarbon resources of similar provinces in Australia.

The effective strength of oceanic plate bounding faults

C. O’Neill, J.-C. Afonso: Supported by ARC Discovery and MQ (commenced 2011)

Summary:  The strength of the ocean faults surrounding the Australian plate controls the long-term fault motions, stress partitioning across the plate boundary and, ultimately, the seismicity of such fault systems. Numerous lines of evidence suggest such faults are far weaker than previous models predict, possibly due to the alteration of crustal and lithospheric rocks into hydrous phases. This is a critical gap in our understanding of such fault systems, and this project will ultimately constrain the weakening mechanisms acting on such faults, and produce a geodynamic-scale model for their effective strength. This project addresses the anomalously weak behaviour of the seismically active faults on the boundary of the Australian plate, in three key geodynamic areas. This will constrain the mechanisms which weaken such faults, and produce a model for their effective strength and evolution over geological timescales.

Down under down under: using multi-scale seismic tomography to image beneath Australia’s Great Artesian Basin

Y. Yang, N.Rawlinson: Supported by ARC Discovery (commenced 2011)

Summary:  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.

Origin of silicic magmas in a primitive island arc: the first integrated experimental and short-lived-isotope study of the Tongan Kermadec system

T. Rushmer, S. Turner: Supported by ARC Discovery (commenced 2011)

Summary:  Silicic magmas are the building blocks of the continental crust and constitute the most hazardous of volcanic eruptions. Silica-rich magmas are found in the Tonga-Kermadec arc, which extends for several thousand km north of New Zealand. Application of a novel combination of experiments and short-lived isotopes to selected magma samples from the primitive Tonga arc will explain the origin of these magmas. The combined technique will also allow us to estimate water content, rates of melting and magma migration at depth, which are critical factors for understanding volcanic hazards. This approach can then be expanded to other parental magma types here and to other arc systems. The Tongan arc forms a large portion of the Australian plate boundary and is one of the most chemically primitive systems known. Oddly, it produces volumes of more evolved, dangerous silicic magmas. The results of this project will establish the source of these magmas and rates of migration, which are fundamental for understanding volcanic hazards.

Oxygenating the Earth: using innovative techniques to resolve the timing of the origin of oxygen-producing photosynthesis in cyanobacteria

M.R. Walter, B.A. Neilan, S.C. George, R.E. Summons, J.W. Schopf: Supported by ARC Discovery (commenced 2011)

Summary:  The early Earth was a hostile place with little oxygen in the atmosphere. Then cyanobacteria (‘blue green algae’) invented oxygen releasing photosynthesis. That profound event affected many fundamental processes, from the course of evolution to the formation of ore deposits. However, estimates of when these bacteria originated are disputed with uncertainties of hundreds of millions of years. We will resolve those uncertainties. We have developed new analytical techniques that we will apply to well preserved 2.7-2.8 billion year old rocks in Western Australia. We will couple that approach to the use of the latest genetic techniques to reveal the origins of living cyanobacteria.

The application of very short-lived Uranium-series isotopes to constraining Earth system processes

S. Turner, T. Dosseto, M. Reagan: Supported by ARC Discovery (commenced 2009)

Summary:  Precise information on time scales is fundamental to understanding natural processes. Uranium series isotopes have revolutionised the way we think about time scales because they can date processes which occurred in the last 10-350 000 years. This proposal will establish new procedures at the recently founded world-class Uranium-series research facility at Macquarie University for analysing very short-lived isotopes (22 years). These new abilities will be utilised to determine the mechanisms of melt/fluid migration and volcano degassing and to ascertain rates of soil production and erosion over time. The methodologies developed will also have application to Uranium exploration and nuclear safeguarding.

How the Earth moves: Developing a novel seismological approach to map the small-scale dynamics of the upper mantle

Y. Yang: Supported by ARC Future Fellowship (commenced 2013)

Summary:  The concept of small-scale convection currents from about 100-400 km below the Earth’s surface is a model proposed to explain the origins of intraplate volcanoes and mountains. However, direct evidence for the physical reality of small-scale convection cells is generally weak. This project will develop a novel seismological approach combining both ambient noise and earthquake data that can image such small-scale upper mantle convection. The outcomes of this project will help to fill the gap left in the Plate Tectonic paradigm by its inability to explain intraplate geological activity (volcanoes, earthquakes, mountains), which would be a significant step towards unifying conceptual models about how the Earth works.

A new approach to quantitative interpretation of paleoclimate archives

D. Jacob: Supported by ARC Future Fellowship and MQ (commenced 2013)

Summary:  Skeletons of marine organisms can be used to reconstruct past climates and make predictions for the future. The precondition is the knowledge of how climatic and environmental information is incorporated into the biominerals. This project will use cutting-edge nano-analytical methods to further our understanding of how organisms build their skeletons.

Dating Down Under: Resolving Earth’s crust - mantle relationships

E. Belousova: Supported by ARC Future Fellowship and MQ (commenced 2012)

Summary:  How the continental crust has grown is a first-order problem in understanding the nature of the surface on which we live. Was most of the crust formed early in Earth’s history or did it grow episodically? Was its growth related to underlying mantle processes? The project will use in-situ isotopic and trace-element microanalysis of the mineral zircon (a geological “time capsule”), extracted from rocks and sediments worldwide, to answer these fundamental questions. It will develop a new model for the timing of crustal formation and the tectonic and genetic links between Earth’s crust and mantle. The results will be relevant to the localisation of a wide range of mineral resources.

The timescales of Earth-system processes: extending the frontiers of uranium-series research

H. Handley: Supported by ARC Future Fellowship and MQ (commenced 2012 S

Summary:  This project will advance our understanding of the timescales of Earth processes using short-lived (22 to 380,000 years) isotopes. The results will provide better constraints on the timescales of magmatic processes and frequency of large-scale eruptions for volcanic hazard mitigation and also soil production rates for landscape erosion studies.

Strength and resistance along oceanic megathrust faults: implications for subduction initiation

C. O’Neill: Supported by ARC Future Fellowship and MQ (commenced 2010)

Summary:  Plate tectonics is enabled by the sinking of dense oceanic lithosphere at ocean trenches - a process known as subduction, but how this process initiates is poorly understood. The development of an incipient subduction zone involves a major evolution of the plate boundary, into an oceanic megathrust fault system, capable of generating devastating earthquakes. An example is the Hjorta Trench, at the Australian-Pacific plate boundary south of Macquarie Island. This project will explore the evolution of this plate-boundary fault system during subduction initiation. Recent advances in our understanding of physical processes along plate-bounding faults will be incorporated into regional geodynamic simulations of this evolving fault system.

Flow characteristics of lower crustal rocks: developing a toolbox to improve geodynamic models

S. Piazolo: Supported by ARC Future Fellowship and MQ (commenced 2012) S

Summary:  This project will investigate in detail how rocks flow in the lowest part of the Earth’s crust. The results will be used to improve sophisticated computer simulations of large-scale geological processes, allowing a better understanding of earthquakes, the formation of volcanic areas and location of energy resources.

From Core to Ore: emplacement dynamics of deep-seated nickel sulphide systems

M. Fiorentini: Supported by ARC Future Fellowship (commenced 2012)

Summary:  Unlike most mineral resources, which are generally concentrated in a wide range of crustal reservoirs, nickel and platinum are concentrated either in the core or in the mantle of our planet. In punctuated events throughout Earth history, large cataclysmic magmatic events have had the capacity to transport and concentrate these metals from their deep source to upper crustal levels. This project aims to unravel the complex emplacement mechanism of these magmas and constrain the role that volatiles such as water and carbon dioxide played in the emplacement and metal endowment of these systems.

How does the continental crust get so hot?

C. Clark: Supported by ARC DECRA (commenced 2012)

Summary:  This project is aimed at constraining the tectonic drivers of high geothermal gradient crustal regimes. The key outcomes of this project are better constraints on the tectonic drivers of high geothermal gradient metamorphism and the development of quantitative tools to assess the evolution of heat within areas of mountain building.

AuScope Australian Geophysical Observing System - Geophysical Education Observatory

C. O’Neill: Supported by DIISR EIF and Macquarie University (commenced 2011)

Summary:  AuScope Australian Geophysical Observing System is designed to augment existing NCRIS AuScope infrastructure with new capability that focuses particularly on emerging geophysical energy issues. It will build the integrated infrastructure that facilitates maximum scientific return from the massive geo-engineering projects that are now being considered – such as deep geothermal drilling – in effect building the platform for treating these as mega geophysical science experiments. AuScope AGOS infrastructure will enable collection of new baseline data including surface geospatial and subsurface imaging and monitoring data, thereby providing for better long-term management of crustal services, particularly in our energy-rich sedimentary basins. The Geophysical Education Observatory – comprising the development of digital real-time connection to existing teaching laboratories, will use the national observatory to provide a unique opportunity for integrating scientific research and education by engaging students, teachers, and the public in a national experiment that is going on in their own backyard

Residual stress investigations of polycrystalline natural diamond aggregates

Venter, S. Piazolo, Luzin: Suported by Braggs Institute, ANSTO (commenced 2013)

Summary:  Our research interest is in the non-destructive investigation of the residual stresses locked into carbonado polycrystalline diamond samples in their raw as-discovered form.

New horizons in geochemical isotopic analysis with a new-generation multicollector plasma mass spectrometer: towards unravelling the deep earth system

W.L. Griffin, N.J. Pearson, S.Y. O’Reilly, E.A. Belousova, Collins, Aitchison, C. Clark, M. Fiorentini, Z.-X. Li, N. Daczko: Supported by ARC LIEF (commenced 2013)

Summary:  A new-generation plasma mass spectrometer will let us develop novel applications in geochemistry to better understand Earth processes. This will enhance Australian Geosciences’ high international profile, and help attract high-quality researchers to attack problems relevant to the Deep Earth Resources National Priority and mineral exploration.

An AZtec electron backscatter diffraction facility for state-of-the-art quantitative microstructural analysis

S. M. Reddy, N.J. McNaughton, N.E. Timms, R.M. Hough, A. van Riessen, P.A. Bland, J.S. Cleverley, M. Fiorentini, B.J. Griffin, A. Kemp, M.R. Kilburn: Supported by ARC LIEF (commenced 2013)

Summary:  Establishing a state-of-the-art quantitative microstructural analysis facility will provide critical infrastructure to complement existing high-spatial resolution microanalytical techniques and facilitate pure and applied research in the geosciences over the next decade.

Craton modification and growth: the east Albany-Fraser Orogen in three-dimensions

H. Tkalcic, B. Kennett, C. Spaggiari, K.Gessner: Supported by ARC LIEF (commenced 2013)

Summary:  The objective of this work is to achieve new, synergistic techniques for delineating the three-dimensional structure of the east Albany-Fraser Orogen in Western Australia, and the lithospheric structure below it. These methods will guide understanding of the potential for mineral resources in this region with little surface geological exposure.

Australian membership of the International Ocean Discovery Program

R.J. Arculus, E.J. Rohling, A.P. Roberts, N.F. Exon, C.J. Yeats, S.Y. O’Reilly, S.C. George, D. Muller, J.C. Aitchison, J.M. Webster, M.F. Coffin, P.M. Vasconcelos, K.J. Welsh, T.C. McCuaig, A.D. George, C.G. Skilbeck, A.T. Baxter, J.M. Hergt, S.J. Gallagher, C.L. Fergusson, C.R. Sloss, A.D. Heap, W.P. Schellart, J.D. Stilwell, J.D. Foden, A.P. Kershaw, W.R. Howard, M.B. Clennell, J.J. Daniell, L.B. Collins: Supported by ARC LIEF (commencing 2014)

Summary:  This project is for an Australian membership of the International Ocean Discovery Program. The Program will recover drill cores, situate observatories, and conduct down-hole experiments in all the world’s oceans from lowest to highest latitudes to address fundamental questions about Earth’s history and processes within four high-priority scientific themes: climate and ocean change - reading the past and informing the future; biosphere frontiers - deep life, biodiversity, and environmental forcing of ecosystems; earth connections - deep processes and their impact on earth’s surface environment; earth in motion - processes and hazards on a human time scale.

A digital mineralogy and materials characterisation hub for petrology, mineralogy, exploration, metallurgy and reservoir characterisation research

B.I. McInnes A. van Riessen, P.A. Bland, S. Iglauer, J.J. Eksteen, A.I. Kemp, J.R. Muhling, M. Fiorentini, N.J. Thébaud, M.T. Wingate, C. Kirkland, G. Senanayake, A.N. Nikoloski: Supported by ARC LIEF (commencing 2014)

Summary:  This project will establish a digital mineralogy and materials characterisation hub for applications in petrology, geometallurgy, reservoir characterisation, environmental science, soil science, mineral processing and extractive metallurgy research. An automated mineral analysis instrument would complement the mineral separation (selFrag HV pulse fragmentation) and microanalytical facilities (SHRIMP/Cameca ion microprobes and ELA-ICP-MS) available to the participants via the John de Laeter Centre for Isotope Research. The instrument and software package making up the FEI QEMSCAN 650F model is the most advanced configuration on the market, and ideally suited for the high level research projects undertaken by the partner institutions.

A new view on diamonds: Deformation textures of polycrystalline diamond

S. Piazolo, Griffins, Venter, Luzin: Supported by Braggs Institute, ANSTO (commenced 2013)

Summary:  In-depth knowledge of the orientation characteristics of diamondites will allow us to interpret these rocks in terms of their deformation history.

GSWA-CET Targeting Products

M. Dentith, T.C. McCuaig, J. Miller, S. Beresford, L. Gallardo, E.-J. Holden, A. George, S. Hagemann, A. Porwal, A. Joly: Supported by GSWA (commenced 2012

Summary:  The GSWA is seeking to improve delivery of exploration-relevant geoscience datasets to industry to attract industry investment in WA as an exploration destination and thereby maintain a pipeline of mineral deposit discoveries that will underpin the revenue base of the State Government into the future. In order to achieve a step change in the exploration relevance of GSWA datasets, it has been recognised that a series of targeting products that help junior to mid-sized exploration companies translate the geoscience datasets into actual ground acquisition and drill target decisions will be critical.

Mineral Systems Flagship Cluster

T.C. McCuaig: Supported by CSIRO Flagship Collaboration Fund (commenced 2013)

Summary:  As Australian mineral exploration moves into areas of deep cover, the expense of exploration drilling wil increase dramatically. Explorers will demand increasingly sophisticated targeting tools to plan drilling programs and an improved understanding of the processes that influence the transport and deposition of metals by ore-forming fluids. The cluster has 3 Themes to deliver on each of the advertised requirements notably: Theme 1: An experimental program to assess the behaviour of meta-stable organic compounds in targeting mineral systems and validate thermodynamic models and interpretations. Theme 2: A complementary field program aimed at providing data from key mineral systems to support the thermodynamic and experimental programs. Theme 3: An integrated thermodynamic treatment of organic and inorganic systems that includes recently documented organometallic complexes.