About Dr Joshua Shea

Professional Background

I'm Dr Joshua Shea, an igneous geochemist, petrologist and postdoctoral researcher at the University of Cambridge, working at the intersection of mantle geochemistry, carbon cycling, and planetary differentiation. My research investigates how deep Earth processes control the mobilisation of volatiles like CO₂ — from mantle melting and metasomatism to surface volcanism — on both Earth and Mars.

With a background in analytical geochemistry, experimental petrology, and thermodynamic modelling, I specialise in olivine-hosted melt inclusions, stable isotope systematics, and volatile-rich alkaline magmas. My work aims to resolve key uncertainties in the deep carbon cycle and to better understand how mantle heterogeneity governs magma generation and the formation of economically and environmentally significant minerals.

Originally from Sydney, I completed my PhD at Macquarie University and now lead international collaborations spanning high-precision isotope analysis, planetary interiors, and open-source tools for geochemical data science. I'm also a strong advocate for ethical Earth science, contributing public commentary on critical minerals, scientific independence, and the future of research in Australia and the UK.

Career Highlights