Research
My research sits at the intersection of igneous geochemistry, experimental petrology, and micro-analytical method development. The unifying question: how do volatile elements move between Earth’s interior and its surface, and what does that tell us about the planet’s deep structure and long-term evolution?
Carbon in the upper mantle
Carbon is volcanism’s most under-measured volatile. It is present at vanishingly low concentrations in basaltic glass, and its isotope composition is sensitive to degassing, contamination, and analytical drift. Working with the Northeast National Ion Microprobe Facility, I developed a SIMS protocol that measures C concentration and δ¹³C concurrently in basaltic glasses with a precision tight enough to resolve mantle-source variability, and produced a set of well-characterised reference glasses for the community.
Applied to olivine-hosted melt inclusions, this method has revised the carbon isotope composition of the convecting upper mantle and uncovered a distinct, isotopically heavy deep primordial reservoir sampled by Icelandic basalts. The downstream implication is a revised long-term carbon cycle.
Funding: NERC IMF direct access; Wellcome Trust EDIA Summer Internship.
Key collaborators: John Maclennan, Marie Edmonds, Ery Hughes (GNS), Glenn Gaetani (WHOI).
Hydrothermal vents and the origin of life
A new experimental thread (started October 2025): testing scenarios that link volcanism and deep volatile cycles to prebiotic chemistry at hydrothermal vents. The work uses piston-cylinder and gas-mixing furnace experiments to recreate geochemically plausible vent conditions, and then asks what organic chemistry follows.
This is interdisciplinary by design — geochemistry, mineralogy, and origins-of-life biochemistry — and is the kind of question that benefits from a student or two willing to learn experimental methods. See the students page.
Mantle melting on Mars
With sample return on the horizon and InSight’s seismic legacy now in hand, the question of how the Martian mantle melts is suddenly tractable. I have argued (in a paper currently addressing reviews at EPSL) that Martian mantle melting operates in a distinct deep regime compared with Earth, with implications for the volatile budget delivered to the surface and what we should expect returned samples to record.
This was the subject of an invited talk at the Mars Forum (JPL/Caltech) in March 2025.
Methods I use
Microbeam and isotopic analysis
SIMS (concurrent C abundance + δ¹³C in basaltic glass), ToF-SIMS, LA-ICP-MS/MS, EPMA, SEM-EDS/EBSD/CL, Raman, CHNS.
Experimental petrology
Piston-cylinder (including rapid-quench), multi-anvil to transition-zone pressures, gas-mixing furnace.
Data science
Python and R for processing micro-analytical data, including statistical workflows for XRF/EDS spectral mapping and machine-learning approaches to spectral processing.
Field
Eastern Australian intraplate volcanism, Cornish granites, Hawaiʻian shield volcanism. Roughly 7.5 months of cumulative field time.
Past work
My PhD (Macquarie, 2022, with Stephen Foley) used eastern Australia as a natural laboratory for lithospheric metasomatism and showed that metasomatised source assemblages are required to generate the region’s intraplate volcanism. That work also clarified how olivine partitioning differs between highly alkaline and tholeiitic melts — a result still being applied in studies of cratonic-margin magmatism.
My Manchester postdoc (with Simon Hunt, 2022–23) characterised the rheological behaviour of Co₂SiO₄ at transition-zone pressures under stress, and produced a statistical workflow for processing XRF and EDS spectral mapping data on experimental charges.