University of Oxford

In a sentence: "For my PhD, I recreated Martian lakes in the lab to see what happened to the planet’s carbon supply — and whether its ancient atmosphere is now buried deep below ground."

Experimental Geochemistry Lab, Department of Earth Sciences, University of Oxford.

Remote sensing is one way to study planetary surfaces — as I did for my Masters — but I knew if I wanted to fully understand Mars, I would need a thorough understanding of geochemistry too. Over four years at Oxford I set up 160 miniature Martian landscapes in the lab. This was with the aim of recreating the mineralogy seen in craters such as Jezero, where NASA’s Perseverance rover is currently exploring, as well as deep below ground where water may percolate even today.

Incredibly, what I discovered was evidence in favour of a buried carbon sink only rarely exposed at the surface today. This could be the fate of a once-substantial earlier atmosphere, and this is important because such an atmosphere would have been vital in keeping the young Mars warm — and, potentially, habitable.

In April 2021 I successfully defended my PhD and was awarded the title of Doctor.

SKILLS

AQUEOUS GEOCHEMISTRY

Conducted in controlled atmosphere glove boxes to simulate the Martian surface. Involves designing and maintaining experiments, intensive monitoring, and the delicate manoeuvring of concentrated acids.

EXPERIMENTAL PETROLOGY

Synthesis of 100% pure fayalite as a proxy for the Martian surface in my experiments. Required use of >1000 ºC furnace, extreme fastidiousness and persistence, and the careful operation of dangerous equipment. 

THERMODYNAMICS

Modelling of experiments in Geochemist's Workbench to identify key conditions; constraining required temperature/oxygen fugacity for fayalite synthesis.

KEY SPECIALISMS

Aqueous geochemistry; Martian limnology; experimental geochemistry; sedimentology; comparative planetology; planetary geology; aqueous thermodynamics.