Argon thermochronometers and the effects of recrystallization. Rocks exhumed from high temperatures in continental settings contain a record of cooling in potassium-bearing minerals, known as thermochronometers, due to the quantitative retention of radiogenic argon below some characteristic closure temperature. However, thermochronometers may be affected by recrystallization processes occurring below such temperatures, and in some cases argon data record the timing of crystallization rather tha ....Argon thermochronometers and the effects of recrystallization. Rocks exhumed from high temperatures in continental settings contain a record of cooling in potassium-bearing minerals, known as thermochronometers, due to the quantitative retention of radiogenic argon below some characteristic closure temperature. However, thermochronometers may be affected by recrystallization processes occurring below such temperatures, and in some cases argon data record the timing of crystallization rather than cooling. Field, microstructural and isotopic analysis will be used to evaluate the effects of recrystallization on the muscovite and potassium-feldspar thermochronometers, particularly in fault zones. Understanding the effects of recrystallization on thermochronometers is critical for studies of the assembly of the continental crust.Read moreRead less
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
Understanding the stratigraphic and structural architecture of late Archean basins and the context of their gold deposits. Gold mined from Archean rocks contributed $4.0 billion to Australia's export income in 2006 and provided the backbone of support for many remote communities. However, production has fallen 40% since 1997 and will be exhausted within 15 years unless major new discoveries are made. The potential to find additional gold deposits remains high, but urgently requires new data and ....Understanding the stratigraphic and structural architecture of late Archean basins and the context of their gold deposits. Gold mined from Archean rocks contributed $4.0 billion to Australia's export income in 2006 and provided the backbone of support for many remote communities. However, production has fallen 40% since 1997 and will be exhausted within 15 years unless major new discoveries are made. The potential to find additional gold deposits remains high, but urgently requires new data and improved exploration techniques to assist in their discovery. The results of this integrated multidisciplinary project will help to arrest the declining discovery rate and thereby sustain this important Australian industry.Read moreRead less
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
Exploring deep Australia: 3-D imaging of the lithosphere beneath south-east Australia using multiple high density seismic arrays. The successful completion of this project will significantly improve our knowledge of the seismic structure of the Australian lithosphere, and hence improve our understanding of how the Australian continent came to be formed. In addition, the tomographic imaging methods that will be developed and applied to the individual and combined seismic arrays have a direct rele ....Exploring deep Australia: 3-D imaging of the lithosphere beneath south-east Australia using multiple high density seismic arrays. The successful completion of this project will significantly improve our knowledge of the seismic structure of the Australian lithosphere, and hence improve our understanding of how the Australian continent came to be formed. In addition, the tomographic imaging methods that will be developed and applied to the individual and combined seismic arrays have a direct relevance to the seismic imaging techniques used by the exploration industry. Finally, the creation of a combined dataset comprising records from ~300 stations will help keep Australia at the leading edge of observational seismology, as other countries (e.g. U.S.) begin to deploy very large seismic arrays.Read moreRead less
How has the continental lithosphere evolved? Processes of assembly, growth, transformation and destruction. We will use new in-situ analytical techniques, developed In-house, to date the formation and modification of specific volumes of the subcontinental lithospheric mantle, and to define the temporal and genetic relationships between mantle events and crustal formation. Quantitative modelling will investigate the geodynamic consequences of spatial and temporal variations in lithosphere composi ....How has the continental lithosphere evolved? Processes of assembly, growth, transformation and destruction. We will use new in-situ analytical techniques, developed In-house, to date the formation and modification of specific volumes of the subcontinental lithospheric mantle, and to define the temporal and genetic relationships between mantle events and crustal formation. Quantitative modelling will investigate the geodynamic consequences of spatial and temporal variations in lithosphere composition and thermal state. Magmatic products will be used to assess the roles of mantle plumes and delamination in construction of the lithosphere and xenolith studies will investigate the evolution of oceanic plateaus. The results will provide a framework for interpreting the architecture of lithospheric terranes and their boundaries.Read moreRead less
How has continental lithosphere evolved? Processes of assembly, growth, transformation and destruction. Novel in-situ analytical and dating techniques will be used on samples from the Earth's mantle and deep crust to define the processes by which the continents and their roots (to depths of 250 km) have been formed, modified or destroyed at different times throughout Earth's 4.6 billion year evolution. The role of oceanic plateaus and mantle plumes in building protocontinents or modifying lithos ....How has continental lithosphere evolved? Processes of assembly, growth, transformation and destruction. Novel in-situ analytical and dating techniques will be used on samples from the Earth's mantle and deep crust to define the processes by which the continents and their roots (to depths of 250 km) have been formed, modified or destroyed at different times throughout Earth's 4.6 billion year evolution. The role of oceanic plateaus and mantle plumes in building protocontinents or modifying lithospheric volumes will be evaluated. The results will provide a more robust framework for interpreting the architecture of Earth's lithosphere and will have relevance to the formation and location of resources such as Ni, PGEs, Au and diamonds.Read moreRead less
Large-scale three dimensional deformation of the lithosphere by subduction and mantle flow. We will be modelling of the dynamics of the Earth's crust and shallow lithosphere in response to the huge stresses created by plate motions. For Australia these stresses are transmitted from the distant plate boundaries, but they have a direct controlling influence on the evolution of the petroleum rich basins of Australia. These basins have reached maturity; further exploration will be in deep water wher ....Large-scale three dimensional deformation of the lithosphere by subduction and mantle flow. We will be modelling of the dynamics of the Earth's crust and shallow lithosphere in response to the huge stresses created by plate motions. For Australia these stresses are transmitted from the distant plate boundaries, but they have a direct controlling influence on the evolution of the petroleum rich basins of Australia. These basins have reached maturity; further exploration will be in deep water where geophysical prospecting methods are unreliable. Model-driven "exploration geodynamics" methods such as those we are developing will be needed to support traditional exploration techniques in these areas.Read moreRead less
Application of Double and Triple Dating of Zircons to Sediment Provenance Studies and to Quantifying Recycling in Sedimentary Rocks. Double and triple dating are exciting new ANU-Yale breakthroughs that can be used to more accurately identify the source of sediment in rivers and sedimentary rocks than is possible using existing techniques. They have fundamental applications in the study of erosion, tracing the source of heavy minerals in titanium deposits and in determining the source of sedi ....Application of Double and Triple Dating of Zircons to Sediment Provenance Studies and to Quantifying Recycling in Sedimentary Rocks. Double and triple dating are exciting new ANU-Yale breakthroughs that can be used to more accurately identify the source of sediment in rivers and sedimentary rocks than is possible using existing techniques. They have fundamental applications in the study of erosion, tracing the source of heavy minerals in titanium deposits and in determining the source of sedimentary sequences that host oil. Under favourable circumstances double dating can be used also to date sediments that are devoid of fossils, which has direct application in oil exploration.Read moreRead less
CRATON EDGES AND SUTURES IN THE AUSTRALIAN MANTLE. A major seismic experiment using recording of distant earthquakes will be used to provide images of 3-D structure in the Earth's crust and mantle along the length of the edge of the Precambrian Australian Shield and across the suture between the South and North Australian cratons within the Shield. Seismic structures derived from different classes of geodynamic models will be compared with seismic results derived from a variety of styles of dat ....CRATON EDGES AND SUTURES IN THE AUSTRALIAN MANTLE. A major seismic experiment using recording of distant earthquakes will be used to provide images of 3-D structure in the Earth's crust and mantle along the length of the edge of the Precambrian Australian Shield and across the suture between the South and North Australian cratons within the Shield. Seismic structures derived from different classes of geodynamic models will be compared with seismic results derived from a variety of styles of data interpretation, including seismic tomography. The experiment will improve understanding of the range of physical processes associated with rifting and building of continents.Read moreRead less