ESSI PhD Projects 2016

School of Earth and Environment University of Leeds http://www.see.leeds.ac.uk/research/essi/ @ESSILeeds

Contents Death in the Oceans: extinction risk in the marine realm ......................................................... 2 The Environmental Geochemistry of Vanadium........................................................................ 4 Collapse of the British - Irish Ice Sheet: the role of climate and sea level changes .................. 7 Catastrophic ice melt and life in the oceans............................................................................ 10 Sclerochronology in deep-sea bivalves .................................................................................... 14 Evolution of a habitable planet: An integrated modelling and geochemical study of the rise of oxygen to modern levels ..................................................................................................... 17 Early animals and plants and their effects on the Earth system: Geochemistry and biogeochemical modelling ....................................................................................................... 21 Archives and modelling of ocean sulphate concentrations over the last 200 million years ... 25 Investigating the role of marine sediments in the global oceanic cycling of nutrient trace metals....................................................................................................................................... 29 Nutrient cycling across the Great Oxidation Event: Dynamics, controls and consequences for Earth surface oxygenation ....................................................................................................... 34 Environmental change during the mid-Permian to Permo-Triassic transition in the deep water Karoo Basin, South Africa .............................................................................................. 37 Carbonate Platform Shutdown and the Rise of Black Shale Giants ........................................ 40 Understanding Earth’s Last Interval of Greater Global Warmth ............................................. 42

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Death in the Oceans: extinction risk in the marine realm Supervisors: Tracy Aze , Alex Dunhill and Paul Wignall (School of Earth and Environment, University of Leeds) Contact email: [email protected] Extinction rates are currently at their highest for 65 million years and are rising at an unprecedented rate. Oceanic ecosystems are particularly vulnerable to rapid environmental change, which is compounded by our lack of knowledge regarding the evolutionary history of many marine groups. This project will employ a multidisciplinary approach to provide the most detailed and comprehensive analysis of extinction risk in a marine group to date. The student will use the planktonic foraminiferal fossil record to address extinction risk in the marine realm; the group have an up-to-date species-level phylogeny (Aze et al. 2011) and have the best species-level fossil record of any group throughout the Cenozoic. Planktonic foraminifera are cosmopolitan unicellular biomineralising marine zooplankton that range from tropical to polar latitudes. They are widely used in palaeoceanographic and palaeoclimatic research and as a result there is a substantial literature detailing their ecological preferences. During the Cenozoic, the Earth transitioned from a high atmospheric CO2 greenhouse world to the lower CO2 icehouse conditions of today, resulting in a fossil record that chronicles biological responses to significant environmental perturbations. Figure 1. A scanning electron microscope image of the planktonic foraminifera Globigerinella adamsi, specimen from core material from the GLOW Cruise to the S.W. Indian Ocean. Objectives: The student will use a random sampling approach to identify extinction events as presented in Aze et al. (2011) to determine whether some species are more susceptible to extinction risk than others and whether risk is linked to ecological or morpholo