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
Seismic constraints on the assembly of cratons. Improved definition of the 3-D seismological structure and nature of the major lithospheric blocks in Australia and their assembly to form the present-day continent will be sought from seismological data. The inclusion of information on the depth extent and character of the lithosphere will improve geological understanding of the evolution of the continent, with relevance to the interaction of the crust and mantle and the placement of mineral res ....Seismic constraints on the assembly of cratons. Improved definition of the 3-D seismological structure and nature of the major lithospheric blocks in Australia and their assembly to form the present-day continent will be sought from seismological data. The inclusion of information on the depth extent and character of the lithosphere will improve geological understanding of the evolution of the continent, with relevance to the interaction of the crust and mantle and the placement of mineral resources.Read moreRead less
Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0668155
Funder
Australian Research Council
Funding Amount
$350,000.00
Summary
Instrumentation for combined seismic and electromagnetic Earth sounding. The set of geophysical recorders will provide the means to enhance understanding of the structure of the Australian continent in 3-D. The interpretation of multiple images of Earth structure will help to link features in the crust and mantle beneath, and provide controls on the evolution and assembly of the present continent, with a major contribution to possible geotransects as recommended in the 2003 National Strategic Pl ....Instrumentation for combined seismic and electromagnetic Earth sounding. The set of geophysical recorders will provide the means to enhance understanding of the structure of the Australian continent in 3-D. The interpretation of multiple images of Earth structure will help to link features in the crust and mantle beneath, and provide controls on the evolution and assembly of the present continent, with a major contribution to possible geotransects as recommended in the 2003 National Strategic Plan for the Geosciences. Combining seismic and electromagnetic methods will provide both geochemeical and geophysical constaints, e.g., on zones of alteration and shear with the potential for deep mineralisation. Read moreRead less
A one million year record of relative sea-level, climatic and environmental changes - Aeolianites of the southern Australian continental margin. This project will (1) further refine two dating methods that will revolutionize Australia's capacity to date geological and archaeological events; (2) ensure that Australia remains in the forefront in applied geochronology and that a sufficient level of technical expertise remains within the country; (3) examine the sensitivity of coastal environments t ....A one million year record of relative sea-level, climatic and environmental changes - Aeolianites of the southern Australian continental margin. This project will (1) further refine two dating methods that will revolutionize Australia's capacity to date geological and archaeological events; (2) ensure that Australia remains in the forefront in applied geochronology and that a sufficient level of technical expertise remains within the country; (3) examine the sensitivity of coastal environments to rapid climate and sea-level changes; (4) increase public awareness of the scientific basis for the unique nature of Australia's coastal landscapes; and (5) may also assist in the exploration of strategically important minerals. Read moreRead less
Submarine explosive eruptions of silicic magma: constraints on products and processes from modern sea-floor examples, ancient successions and experiments. Volcanoes are common on the sea-floor. Many have been the sites of devastating explosive eruptions throughout Earth history, producing thick layers of pumice and volcanic ash in both modern and ancient ocean basins. None of these events has been witnessed, hence, little is known about submarine explosive eruptions and the associated volcanoes. ....Submarine explosive eruptions of silicic magma: constraints on products and processes from modern sea-floor examples, ancient successions and experiments. Volcanoes are common on the sea-floor. Many have been the sites of devastating explosive eruptions throughout Earth history, producing thick layers of pumice and volcanic ash in both modern and ancient ocean basins. None of these events has been witnessed, hence, little is known about submarine explosive eruptions and the associated volcanoes. This detailed, multidisciplinary study will link exploration of modern explosive sea-floor volcanoes (western Pacific Ocean), field-work on older, submarine volcanic formations (Japan, Greece) and experiments that simulate explosive eruptions and their products. The results will elucidate sea-floor explosive volcanism and its contribution to the geology of ocean basins.Read moreRead less
The abundance and isotope composition of pyrogenic carbon in tropical savannas. Tropical savanna burning represents an important but poorly understood component of the global carbon cycle. This project will quantify the dynamics of pyrogenic carbon (charcoal, soot, biochar) production and dispersal during savanna fires. Pyrogenic carbon is important because it can persist in the environment for thousands of years. Hence it represents both a 'sink' for carbon and a source of information about pas ....The abundance and isotope composition of pyrogenic carbon in tropical savannas. Tropical savanna burning represents an important but poorly understood component of the global carbon cycle. This project will quantify the dynamics of pyrogenic carbon (charcoal, soot, biochar) production and dispersal during savanna fires. Pyrogenic carbon is important because it can persist in the environment for thousands of years. Hence it represents both a 'sink' for carbon and a source of information about past environments. The project will also assist in validating 'biochar' as a new tool for carbon sequestration, an enable a deeper understanding of the interactions between fire, humans, vegetation and climate.Read moreRead less
Investigating mineral alteration and infilling of discontinuities in naturally deformed rocks as a guide to rock mass rheology. Structural analysis of naturally deformed rock will be used to investigate the origin, physical characteristics and frictional behaviour of naturally formed discontinuity surfaces. Discontinuities in naturally deformed rock masses are typically altered and infilled with complex combinations of mineral matter and are a major control on the rheology, including strength a ....Investigating mineral alteration and infilling of discontinuities in naturally deformed rocks as a guide to rock mass rheology. Structural analysis of naturally deformed rock will be used to investigate the origin, physical characteristics and frictional behaviour of naturally formed discontinuity surfaces. Discontinuities in naturally deformed rock masses are typically altered and infilled with complex combinations of mineral matter and are a major control on the rheology, including strength and stability, of rock masses in engineering excavations. By combining structural geology techniques and laboratory experiments, and with reference to existing data on field-scale rock mass deformation derived from engineering rock mechanics investigations, a methodology for predicting rock mass rheology from fundamental geological observations will be devised and tested.Read moreRead less
Precise global time scale for the oxidation of Earth's atmosphere between 2.6 and 2.0 billion years ago. The rock record from 2600 to 2000 million years ago preserves evidence for dramatically fluctuating greenhouse and icehouse climates at the same time as, and possibly caused by, change from an oxygen-deficient to an oxygen-rich atmosphere. Although the global changes are well-documented, correlation of their timing and duration between continents is poorly constrained. This project aims to re ....Precise global time scale for the oxidation of Earth's atmosphere between 2.6 and 2.0 billion years ago. The rock record from 2600 to 2000 million years ago preserves evidence for dramatically fluctuating greenhouse and icehouse climates at the same time as, and possibly caused by, change from an oxygen-deficient to an oxygen-rich atmosphere. Although the global changes are well-documented, correlation of their timing and duration between continents is poorly constrained. This project aims to redress that problem by producing a precise calibration of the global changes by analysis of the rock records in Australia, Canada and South Africa. It will provide a much needed time framework within which long-term feedback between atmospheric composition and climate can be understood.Read moreRead less
Nickel iron sulphide mineralogy: the link between mineral transformations and microstructure and magnetic properties. This project is about measuring the rate at which minerals transform or react and how metal diffusion controls these reactions. Metal diffusion in sulphides is much more rapid that in silicates and is still very significant at low temperatures (< 300 C). In this project, we are trying to measure the rate at which the principal ore of nickel, pentlandite, transforms to violarite ....Nickel iron sulphide mineralogy: the link between mineral transformations and microstructure and magnetic properties. This project is about measuring the rate at which minerals transform or react and how metal diffusion controls these reactions. Metal diffusion in sulphides is much more rapid that in silicates and is still very significant at low temperatures (< 300 C). In this project, we are trying to measure the rate at which the principal ore of nickel, pentlandite, transforms to violarite, another important nickel rich sulphide that forms from it in the upper parts of ore bodies. The arrangement of the metal atoms in these minerals is sensitive to temperature, so it may be used as a geothermometer.Read moreRead less
Looking back to see the future: Change in the Lambert Glacier and the East Antarctic Ice Sheet. To develop a comprehensive understanding of the Lambert Glacier of East Antarctica, from the time of the last maximum glaciation to the present, through an integrated and interdisciplinary study combining new field evidence - ice retreat history, geodetic measurements of crustal rebound, satellite measurements of present ice heights and changes therein - with other geological and glaciological data an ....Looking back to see the future: Change in the Lambert Glacier and the East Antarctic Ice Sheet. To develop a comprehensive understanding of the Lambert Glacier of East Antarctica, from the time of the last maximum glaciation to the present, through an integrated and interdisciplinary study combining new field evidence - ice retreat history, geodetic measurements of crustal rebound, satellite measurements of present ice heights and changes therein - with other geological and glaciological data and numerical geophysical modelling advances. The project contributes to the quantitative characterisation of the complex interactions between ice-sheets, oceans and solid earth within the climate system. Outcomes have implications for geophysics, glaciology, geomorphology, climate, and past and future sea-level change.Read moreRead less