The application of clumped isotope thermometry to the terrestrial environment. Clumped-isotope geochemistry, a novel method for measuring the temperature of formation of carbonate minerals, will be applied to terrestrial materials (soil carbonates, lake deposits and speleothems) from Australia and New Zealand. The method relates the abundance or 'clumping' of rare isotopes (for example, carbon dioxide of mass 47 as carbon-13, oxygen-18, oxygen-16) extracted from carbonates to their formation tem ....The application of clumped isotope thermometry to the terrestrial environment. Clumped-isotope geochemistry, a novel method for measuring the temperature of formation of carbonate minerals, will be applied to terrestrial materials (soil carbonates, lake deposits and speleothems) from Australia and New Zealand. The method relates the abundance or 'clumping' of rare isotopes (for example, carbon dioxide of mass 47 as carbon-13, oxygen-18, oxygen-16) extracted from carbonates to their formation temperature and is independent of the oxygen-18:oxygen-16 value of the host water from which the mineral precipitated. The materials to be investigated span the Last Glacial-Interglacial Transition and will provide robust past temperature estimates and the delta-oxygen-18 values of waters, thereby permitting hydrological balances (for example, precipitation/evaporation) to be constructed. Read moreRead less
Diatom lipids to reveal sea-ice history in remote Antarctic regions. This project aims to understand seasonal Antarctic sea-ice extent using molecular, geochemical, elemental and genomic characteristics of specific marine phytoplankton (diatoms). Little is known of the seasonal sea-ice variation and the position of the summer sea-ice extent a million years before satellite records, but this information is critical to determining air-sea gas exchange and ecosystem food web regulation. This projec ....Diatom lipids to reveal sea-ice history in remote Antarctic regions. This project aims to understand seasonal Antarctic sea-ice extent using molecular, geochemical, elemental and genomic characteristics of specific marine phytoplankton (diatoms). Little is known of the seasonal sea-ice variation and the position of the summer sea-ice extent a million years before satellite records, but this information is critical to determining air-sea gas exchange and ecosystem food web regulation. This project will unite geochemical and biological approaches to provide the data to improve past Antarctic ecosystem and climate models where sea-ice data is missing. Studying diatom biomarkers in deep sea cores from Australia’s Southern Ocean will redefine knowledge of Antarctic climate and provide data necessary to improve global ecosystem and climate models.Read moreRead less
Were abrupt changes in the Precambrian global carbon cycle the trigger for animal appearance and radiation on Earth? The origin of complex life and the properties that allow that life to be sustained on this planet are recorded within the geologic record. This project will reveal the role that severe perturbations of the global carbon cycle and climate had in triggering the step-wise change to animal life after billions of years of only single cell organisms.