Seismic tomography using signal and noise: A new window into deep Earth. This project will combine traditional imaging techniques based on earthquake records, and state of the art ambient noise tomography, which exploits oceanic and atmospheric disturbances, to construct detailed models of the crust and upper mantle beneath southeast Australia. The national benefits of this research include: a vastly improved understanding of the deep architecture of the Australian Plate, and how it has evolved ....Seismic tomography using signal and noise: A new window into deep Earth. This project will combine traditional imaging techniques based on earthquake records, and state of the art ambient noise tomography, which exploits oceanic and atmospheric disturbances, to construct detailed models of the crust and upper mantle beneath southeast Australia. The national benefits of this research include: a vastly improved understanding of the deep architecture of the Australian Plate, and how it has evolved over time; a paradigm shift in the interpretation of seismic data, which will enhance Australia's reputation in the international scientific community; and important new constraints on the broad scale geology of prospective regions that host world class mineral deposits.Read moreRead less
Dynamics and Chemical Evolution of the Earth's Early Mantle. Preliminary numerical results demonstrate that the Earth's mantle may have been compositionally stratified early in its history through a novel interaction between compositional buoyancies and viscosity stratification. This result has important implications for the evolution of the crust and for the chemical and isotopic evolution of the mantle. It also complements recent geochemical evidence for the extraction of a basaltic componen ....Dynamics and Chemical Evolution of the Earth's Early Mantle. Preliminary numerical results demonstrate that the Earth's mantle may have been compositionally stratified early in its history through a novel interaction between compositional buoyancies and viscosity stratification. This result has important implications for the evolution of the crust and for the chemical and isotopic evolution of the mantle. It also complements recent geochemical evidence for the extraction of a basaltic component from the early upper mantle. It is proposed to explore the robustness of this phenomenon in two and three dimensions, its longer-term behaviour, and the evolution of the stratification as the mantle cools to its present condition.Read moreRead less
The seismic signature of crustal fluids. Fluids are expected to profoundly modify the seismic properties of the cracked rocks of Earth's upper crust (to depths of about 15 km) but there are so far few relevant laboratory measurements. Through the development and application of novel experimental techniques we plan to build a better laboratory-based understanding of the seismic properties of fluid-saturated crustal rocks. The outcome will be an improved capacity to monitor the presence of fluid ....The seismic signature of crustal fluids. Fluids are expected to profoundly modify the seismic properties of the cracked rocks of Earth's upper crust (to depths of about 15 km) but there are so far few relevant laboratory measurements. Through the development and application of novel experimental techniques we plan to build a better laboratory-based understanding of the seismic properties of fluid-saturated crustal rocks. The outcome will be an improved capacity to monitor the presence of fluids in diverse situations ranging from geothermal power generation and waste disposal to earthquake fault zones. Read moreRead less
Growth and Decay of ice sheets during glacial cycles:the example of Europe. The proposal is to develop a comprehensive model for the growth and decay of the ice sheets of Europe during the last glacial cycle, using a combination of diverse field evidence with geophysical modelling. The outcomes provide boundary conditions for climate models (times of inception and decay, ice limits, ice thickness) including processes driving climate as well as constraints on the Earth's mantle viscosity. Thu ....Growth and Decay of ice sheets during glacial cycles:the example of Europe. The proposal is to develop a comprehensive model for the growth and decay of the ice sheets of Europe during the last glacial cycle, using a combination of diverse field evidence with geophysical modelling. The outcomes provide boundary conditions for climate models (times of inception and decay, ice limits, ice thickness) including processes driving climate as well as constraints on the Earth's mantle viscosity. Thus the project contributes to the quantitative characterisation of both climate change and planetary structure. In an Australian context, these outcomes form important elements in the development of predictive models for sea-level change.Read moreRead less
Taming the nonlinearity of geophysical inversions. This project will develop new ways to extract information from complex geophysical data sets used to construct images of the Earth's interior. Applications will be important to indirect imaging problems in the physical and engineering sciences and particularly to the discovery of resources within the Earth upon which Australian society is dependent.
From crust to core: probing the heterogeneity of the Earth with seismic arrays. Seismic array deployments will be used for a variety of studies including tomographic mapping of upper mantle structure, coda analysis for crustal properties and delineation of deeper Earth structure. The high resolution information on crustal and upper mantle structure will provide important detail on the building blocks of the Australian plate at depth. This class of information helps to refine our understanding o ....From crust to core: probing the heterogeneity of the Earth with seismic arrays. Seismic array deployments will be used for a variety of studies including tomographic mapping of upper mantle structure, coda analysis for crustal properties and delineation of deeper Earth structure. The high resolution information on crustal and upper mantle structure will provide important detail on the building blocks of the Australian plate at depth. This class of information helps to refine our understanding of the way that the Australian continent has been assembled with regard to the interaction of the crust and mantle and the emplacement of mineral resources.Read moreRead less
Plate kinematics to plate dynamics: understanding plate boundary processes at the global scale. This proposal aims to create geodynamic models which can be used a basis for a new, smart resource exploration and extraction industry which uses simulation to help characterize regions where traditional geophysical imaging alone is not able to penetrate. It provides essential scientific underpinnings for
The Australian Computational Earth System Simulator Major National Research Facility (ACcESS).
NUMERICAL MODELS OF PLATE TECTONICS, MANTLE CONVECTION AND SLAB DYNAMICS WITH EVOLVING FAULTS. We plan to develop a method for simulating large-scale
geological structures with a much improved treatment
of tectonic faults in 3D.
Current computer models have sharp geological faults at plate
boundaries represented by broad, blurred zones. New techniques
for modeling cracks in engineering structures will be scaled up to
the whole Earth.
This will help us to understand how the Earth's p ....NUMERICAL MODELS OF PLATE TECTONICS, MANTLE CONVECTION AND SLAB DYNAMICS WITH EVOLVING FAULTS. We plan to develop a method for simulating large-scale
geological structures with a much improved treatment
of tectonic faults in 3D.
Current computer models have sharp geological faults at plate
boundaries represented by broad, blurred zones. New techniques
for modeling cracks in engineering structures will be scaled up to
the whole Earth.
This will help us to understand how the Earth's plates move and
interact now and in the past and how the structure of the continents
arose.
Not only is this intrinsically interesting, it
will also be of immediate practical benefit to geological modelers.Read moreRead less
Beneath Bass Strait: linking Tasmania and mainland Australia using a novel seismic experiment. A new low-cost approach based on background seismic energy and earthquake recordings will be used to construct three-dimensional maps of the deep structure beneath Bass Strait. Understanding the broad scale geology of southeast Australia is of national importance because the area is host to an abundance of petroleum, geothermal and mineral resources.
Three-dimensional flow, temperature and melting distributions in mantle subduction zones. We will predict spatial distributions and time evolution of temperature and magma production in subduction zones, where cold oceanic plates sink into the Earth's mantle, recycle crust and sediments, and generate volcanic arcs. Three-dimensional laboratory experiments, including 3-D flow visualization and high-resolution temperature measurements, will model slab segments, different rates and modes of subduct ....Three-dimensional flow, temperature and melting distributions in mantle subduction zones. We will predict spatial distributions and time evolution of temperature and magma production in subduction zones, where cold oceanic plates sink into the Earth's mantle, recycle crust and sediments, and generate volcanic arcs. Three-dimensional laboratory experiments, including 3-D flow visualization and high-resolution temperature measurements, will model slab segments, different rates and modes of subduction and upward transport of melt. Ocean trench migration (?rollback? subduction) is of special interest because it gives patterns of temperature and vertical motion most conducive to melting. Results will be used to interpret geochemical and seismic data from the Tonga subduction zone in the South Pacific.Read moreRead less