Unraveling the oxidative geochemistry of nanoparticulate mackinawite in acid sulfate soil landscapes. Acid sulfate soils impact over 8 million ha of valuable coastal land in Australia, and over 24 million ha throughout the world. Drainage from acid sulfate soil waterways is a major threat to water quality, ecosystem health, agricultural sustainability and fisheries productivity. The practical benefits of this project arise from an improved understanding of the processes controlling water qualit ....Unraveling the oxidative geochemistry of nanoparticulate mackinawite in acid sulfate soil landscapes. Acid sulfate soils impact over 8 million ha of valuable coastal land in Australia, and over 24 million ha throughout the world. Drainage from acid sulfate soil waterways is a major threat to water quality, ecosystem health, agricultural sustainability and fisheries productivity. The practical benefits of this project arise from an improved understanding of the processes controlling water quality and associated resources in these areas. The intellectual benefits include the development of novel geochemical concepts involving sulfur minerals that are central to coastal rivers, wetlands and estuaries. This project will enhance Australia's capacity for sustainable environmental management.Read moreRead less
Sulfide Partial Melting at Broken Hill: Process and Implications. Based entirely on experimental studies, we suggested that the sulfide ore at Broken Hill, N.S.W., partially melted during granulite-facies metamorphism. Our subsequent discovery of sulfide melt inclusions in silicates associated with the ore strongly supports this assertion. This proposed research will evaluate the extent of melting and the composition of such a melt as well as the effect of this melt on the rocks surrounding the ....Sulfide Partial Melting at Broken Hill: Process and Implications. Based entirely on experimental studies, we suggested that the sulfide ore at Broken Hill, N.S.W., partially melted during granulite-facies metamorphism. Our subsequent discovery of sulfide melt inclusions in silicates associated with the ore strongly supports this assertion. This proposed research will evaluate the extent of melting and the composition of such a melt as well as the effect of this melt on the rocks surrounding the ore. The results of this basic research will not only impact on Broken Hill genetic models specifically, but could profoundly effect our understanding of metamorphic and magmatic sulfide deposits globally.Read moreRead less
The Origin of Australian Opal Deposits: Unlocking the Secrets of an Australian Icon. Opal is the National Gemstone of Australia. With over 95% of world's precious opal being mined in Australia, this precious mineral is not only one of our major export earners but also the life blood of many central Australian townships. Despite its economic significance and long history of mining little is known about the formation of opal. Consequently, exploration is still based on old-fashioned prospecting me ....The Origin of Australian Opal Deposits: Unlocking the Secrets of an Australian Icon. Opal is the National Gemstone of Australia. With over 95% of world's precious opal being mined in Australia, this precious mineral is not only one of our major export earners but also the life blood of many central Australian townships. Despite its economic significance and long history of mining little is known about the formation of opal. Consequently, exploration is still based on old-fashioned prospecting methods rather than on genetic exploration models that have made base metal exploration so successful. The aim of this project is to investigate the processes controlling the formation of Australian opal and to use this information to construct an exploration model that will lead to more effective and efficient exploration methods.Read moreRead less
Resolving uncertainty over the importance of N-fixation versus denitrification in coastal systems. Nutrient enrichment of coastal waters is a significant national and international problem requiring urgent action. Despite many studies and many millions of dollars in research funding we know virtually nothing about the relative importance of the major nitrogen cycling pathways, N-fixation and denitrification. Many hundred's of millions of dollars are likely to be spent over the next ten years on ....Resolving uncertainty over the importance of N-fixation versus denitrification in coastal systems. Nutrient enrichment of coastal waters is a significant national and international problem requiring urgent action. Despite many studies and many millions of dollars in research funding we know virtually nothing about the relative importance of the major nitrogen cycling pathways, N-fixation and denitrification. Many hundred's of millions of dollars are likely to be spent over the next ten years on the management of nitrogen enrichment of Australia's coastal waters. This study will use a new method for directly measuring N-fixation to resolve uncertainty over the importance of N-fixation versus denitrification in coastal systems; information which is critical for the efficient allocation of management resources.Read moreRead less
Understanding the Sibao Orogenic Belt in South China: A Part of the Rodinian Supercontinent Assembly Adjacent to Australia. The Sibao Orogenic Belt (SOB) in South China is regarded as one of the worldwide 1300-1000 Ma mountain belts that record the assembly of the supercontinent Rodinia. However, recent work suggests that some of these mountain belts, including the SOB, were probably active until 900 Ma, thus questioning parts of the early Rodinia reconstructions. In this study we aim to deter ....Understanding the Sibao Orogenic Belt in South China: A Part of the Rodinian Supercontinent Assembly Adjacent to Australia. The Sibao Orogenic Belt (SOB) in South China is regarded as one of the worldwide 1300-1000 Ma mountain belts that record the assembly of the supercontinent Rodinia. However, recent work suggests that some of these mountain belts, including the SOB, were probably active until 900 Ma, thus questioning parts of the early Rodinia reconstructions. In this study we aim to determine the ages, and geochemical and structural characteristics of key tectonic units in the SOB. This will lead to a better understanding of the assembly process of Rodinia, and events occurring in continental blocks adjacent to Australia at that time.Read moreRead less
The Southern Ocean's role in determining atmospheric CO2 levels: new insights from novel biogenic silica records of seawater pH. About half the emissions from the burning of fossil fuel since the Industrial Revolution have been absorbed by the oceans. However, considerable uncertainty surrounds the consequences of and the extent to which the oceans will continue to sequester CO2 into the future. This research will improve existing limited knowledge of the key biological and related ocean process ....The Southern Ocean's role in determining atmospheric CO2 levels: new insights from novel biogenic silica records of seawater pH. About half the emissions from the burning of fossil fuel since the Industrial Revolution have been absorbed by the oceans. However, considerable uncertainty surrounds the consequences of and the extent to which the oceans will continue to sequester CO2 into the future. This research will improve existing limited knowledge of the key biological and related ocean processes that transfer CO2 between the surface and depth, and the poorly understood effects on marine ecosystems of increasing ocean acidity due to CO2 absorption. This knowledge will contribute to predicting the course of future climate change and gauging the impacts on marine life and production systems.Read moreRead less
Partial melting in natural metal-silicate and silicate systems: rheological and geochemical implications for the Earth and other planets. Understanding how fluid and melts migrate through the Earth's crust is vital to predicting how important minerals, metals and oil can be concentrated. Understanding fluid-rock systems therefore contribute to an environmentally sustainable Australia (Research Priority 1). Furthering our knowledge of permeable networks through the use of dynamic experiments is a ....Partial melting in natural metal-silicate and silicate systems: rheological and geochemical implications for the Earth and other planets. Understanding how fluid and melts migrate through the Earth's crust is vital to predicting how important minerals, metals and oil can be concentrated. Understanding fluid-rock systems therefore contribute to an environmentally sustainable Australia (Research Priority 1). Furthering our knowledge of permeable networks through the use of dynamic experiments is an innovative way to study their development within naturally evolving crustal systems as they respond to changing physical and chemical conditions. Thus, this proposal is also directly concerned with the continuing aim of building a sustainable Australia through knowledge of deep Earth resources.Read moreRead less
Toward the use of metal stable isotopes in geosciences. Metal stable isotopes (MSI: Mg, Fe, Cu, Zn, Ga) have enormous potential applications (basic and applied) in Geosciences and beyond. However the use of these elements as geochemical tracers and petrogenetic tools requires: (1) the definition of their isotopic composition in Earth key reservoirs and in reference materials such as the chondritic meteorites; (2) Understanding and quantification of the causes of MSI fractionations during geolog ....Toward the use of metal stable isotopes in geosciences. Metal stable isotopes (MSI: Mg, Fe, Cu, Zn, Ga) have enormous potential applications (basic and applied) in Geosciences and beyond. However the use of these elements as geochemical tracers and petrogenetic tools requires: (1) the definition of their isotopic composition in Earth key reservoirs and in reference materials such as the chondritic meteorites; (2) Understanding and quantification of the causes of MSI fractionations during geological processes. By a unique combination of in-situ and solution geochemical analytical techniques avaliable now through frontier technology and method development we aim to establish a conceptual and theoretical framework for the use of MSI in Geosciences.Read moreRead less
Diamond genesis: cracking the code for deep-Earth processes. The project will provide new insights into the processes by which diamond crystallises in the Earth's mantle, and will deliver information directly relevant to interpreting the diamond prospectivity of the Australian continent. The development of a new diamond mine in Australia, or by Australian companies abroad, would be a major addition to the economy and Australian-based industry. Another outcome of this research will be further de ....Diamond genesis: cracking the code for deep-Earth processes. The project will provide new insights into the processes by which diamond crystallises in the Earth's mantle, and will deliver information directly relevant to interpreting the diamond prospectivity of the Australian continent. The development of a new diamond mine in Australia, or by Australian companies abroad, would be a major addition to the economy and Australian-based industry. Another outcome of this research will be further development of methodologies for identification of sources of individual diamonds, relevant to the international Kimberley Process for reducing theft and illegal diamond trade. The project will be a highly visible Australian contribution to this global social and economic problem.Read moreRead less
Trace element geochemistry of microbialites: towards an independent record of biogenicity, microbial communities, and seawater chemistry. A vast amount of Australia's mineral wealth is held in rocks of Precambrian age, yet those rocks are notoriously difficult to date and correlate owing to the rarity of fossils. Successful discrimination of different microbialites using biochemically sensitive trace elements will provide a firm basis and rationale for stromatolite biostratigraphy and greatly in ....Trace element geochemistry of microbialites: towards an independent record of biogenicity, microbial communities, and seawater chemistry. A vast amount of Australia's mineral wealth is held in rocks of Precambrian age, yet those rocks are notoriously difficult to date and correlate owing to the rarity of fossils. Successful discrimination of different microbialites using biochemically sensitive trace elements will provide a firm basis and rationale for stromatolite biostratigraphy and greatly increase our ability to understand the geological evolution and distribution of Precambrian rocks and resources. Additionally, a better understanding of the information content of stromatolites will yield considerable insight into the origin of life on Earth and its relationship to Earth's evolving chemistry and environment. Read moreRead less