Miss Madeleine Stow
2018 - present: PhD, Durham University
2017-2018: MSc in Geochemistry, University of St Andrews
2013-2017: BSc in Geology, University of Edinburgh
Intrusive investigations with transition metal (Fe-V-Zn) stable isotopes
Developments in analytical techniques have permitted the detection of small variations in the isotopic composition of transition metals in igneous rocks and minerals. Stable isotope fractionation is fundamentally driven by differences in bond strength between phases, which is proportional to the valence state of elements, and inversely related to bond co-ordination number. Therefore, stable isotopes can be used to study both the intensive parameters of igneous systems (e.g. oxygen fugacity) and processes including melting, fractional crystallisation and alteration.
Previous studies on stable isotopes in igneous systems tend to focus on mantle rocks or extrusive lavas. My research aims to investigate the controls on the fractionation of Fe, V and Zn stable isotopes during the crystallisation of intrusive igneous rocks. Several intrusive complexes with different parent magma chemistries and fractional crystallisation histories will be targeted, starting with the Boggy Plain Zoned Pluton in SE Australia. The Fe, V and Zn isotopic composition of whole rock samples and mineral separates will be measured using Multi-Collector Inductively-Coupled Plasma Mass-Spectrometry (MC-ICP-MS) at Durham University. These three isotopic systems are chosen because they have different chemical characteristics so are fractionated by different processes in magma chambers allowing isolation of the controls on fractionation. These systematics can then be used to investigate specific processes that occur during crustal magmatic evolution, including oxide fractionation and sulfide saturation.