"PhD Studentship: An experimental study of mineral reactivity and critical metal mobility in faulted granites"

The University of Manchester - Earth and Environmental Sciences

This 3.5 year PhD project is fully funded and home students, and EU students with settled status, are eligible to apply. The successful candidate will receive an annual tax-free stipend set at the UKRI rate (£20,780 for 2025/26) and tuition fees will be paid. We expect the stipend to increase each year. The start date is flexible.

Growing demand for critical metals necessitates exploration in traditionally unconventional ore deposits. The push for secure local supply chains has driven the commercialisation of lithium, a key component in battery technology, found in brines associated with geothermal prospects e.g. United Downs in Cornwall, Upper Rhine Graben in Alsace. In the UK, Cornish granites are being explored by Cornish Lithium, British Lithium, Cornish Tin and Cornwall Resources, for a range of critical metals including lithium, tin, tungsten, copper, gold and silver. Demand is such that some of these companies are evaluating the potential for the extraction of Li, and other critical metals, from naturally-occurring brines derived from granite-water interaction and thereby avoiding energy intensive, extractive mining. Faults play a key role in these systems by acting as fluid flow conduits and sites of mineralisation. (Caine et al., 1996; Sibson, 1987). Mechanical deformation during faulting reduces grain size, increases surface area, and creates fresh reactive mineral surfaces, potentially enhancing fluid–rock interaction (Wintsch, 1995). Lithium-rich groundwaters identified in faulted Cornish granites suggest that deformation-driven reactivity may be a critical control on metal mobility.

The aim of this PhD project is to experimentally quantify how mechanical deformation in fault zones enhances mineral reactivity and promotes the leaching of lithium and other critical metals into pore fluids. The project will test the hypothesis that fault-related deformation increases reactivity, making fault zones prime locations for the enrichment of lithium and other critical metals in pore waters.

This project combines laboratory experiments, field studies and microstructural analysis. The experimental component will involve rock deformation experiments conducted under controlled pressure–temperature conditions, focusing on the development of fault-related microstructures and associated changes in fluid chemistry (Farrell et al, 2025). These results will be complemented by field-based structural geology and petrographic studies of natural fault rocks (Evans et al, 2025). The findings will provide fundamental insights into aqueous critical-metal deposits, particularly lithium resource models, with additional implications for fluid recharge processes in geothermal energy systems.

The successful candidate will be based at the University of Manchester and will work within the globally renowned Rock Deformation Laboratory, known for its seminal contributions to structural geology and rock mechanics. Full training will be provided in:

• Field-based structural geology techniques
• Optical, electron and chemical microscopy
• Operation and calibration of standard petrophysical apparatus and bespoke high-pressure, high-temperature deformation machines.
• Geochemical and fluid analysis techniques

You will join a diverse and collaborative research environment and have opportunities to present your work to both academic and industrial audiences, working alongside researchers applying experimental results to practical geological challenges.

Applicants should have, or expect to achieve, at least a 2.1 honours degree or a master’s (or international equivalent) in a relevant science or engineering related discipline.

To apply, please contact the main supervisor, Dr Natalie Farrell - natalie.farrell@manchester.ac.uk. Please include details of your current level of study, academic background and any relevant experience and include a paragraph about your motivation to study this PhD project.