Hot rocks and hidden metals: The porosity puzzle of the Cornubian batholith

Director of Studies:  Dr Michelle Harris  

2nd Supervisor:  Dr Andrew Parsons  

3rd Supervisor: Dr Katie Jones  

4th Supervisor:  Dr Giuliano Laudone  

Applications are invited for a 3.5 years PhD studentship. The studentship will start on 1 October 2026

Scientific background
The Cornubian batholith of SW England represents a crucial resource for the UK’s Energy Transition, providing a source of critical metals (Li, Sn, W) and heat for geothermal projects. Deep crustal fluid flow and the resulting fluid-rock reactions that mobilise heat and metals into the fluids are key to its potential as an economic resource. However, the nature of the porosity and permeability which controls fluid flow within these rocks is poorly understood, limiting our ability to capitalise on their resource potential. Central to this problem is the uncharacterised role of microporosity (i.e. grain scale) versus the broader macro-scale porosity and permeability generated by local and regional structures (e.g., faults and fractures). How does microporosity vary across the granites, how is this impacted by mineralogy and macroscopic structures, and how can we scale lab-based measurements of porosity with field observations? The answers to these questions will provide a new and much needed understanding of the controls of fluid-flow processes in the Cornubian batholith and their controls on the fluid mobilization of geothermal heat and metals. 

Representative samples and field structural data will be collected from a number of accessible sites across the Cornubian batholith. Discrete samples will be fully characterised for mineralogy (SEM) and bulk rock geochemistry (ICP-MS, XRF). Internal pore structure will be investigated in detail using helium pycnometry, mercury porosimetry and micro-CT scanning. These datasets will be used in combination with the Porexpert Research Suite to construct numerical models that simulate fluid flow, allowing for the calculation of permeability. These results will be integrated with the field data to determine the variability in microporosity and permeability and how these are influenced by mineralogy and larger scale structures.

The successful candidate will receive all necessary training including field sampling and measurement, as well as direct training in the safe and effective operation of the different instruments and in advanced data processing workflows for the data outputs and modelling tools

We seek a motivated individual with an interest in Earth Science and a desire to develop expertise in analytical techniques and modelling/basic programming. 

Simons et al., 2016. The petrogenesis of the Early Permian Variscan granites of the Cornubian Batholith: Lower plate post-collisional peraluminous magmatism in the Rhenohercynian Zone of SW England. Lithos 260 p76-94 http://dx.doi.org/10.1016/j.lithos.2016.05.010

Stanek & Geraud 2019. Granite microporosity changes due to fracturing and alteration: secondary mineral phases as proxies for porosity and permeability estimation. JGR Solid Earth 10, p251-274 https://doi.org/10.5194/se-10-251-2019

Schwarzenbach & Harris 2025 Hydrothermal alteration of the oceanic lithosphere. Treatise of Geochemistry 3rd Edition Vol 2 p1-37 https://doi.org/10.1016/B978-0-323-99762-1.00016-4

Jones, KL, Matthews, GP & Laudone, GM 2020, 'The effect of irradiation and radiolytic oxidation on the porous space of Gilsocarbon nuclear graphite measured with mercury porosimetry and helium pycnometry', Carbon, vol. 158, pp. 256-266. https://doi.org/10.1016/j.carbon.2019.11.084

Matthews, GP, Levy, CL, Laudone, GM, Jones, KL, Ridgway, CJ, Halllin, I, Gazze, SA, Francis, L, Whalley, WR, Schoelkopf, J & Gane, PAC 2018, 'Improved Interpretation of Mercury Intrusion and Soil Water Retention Percolation Characteristics by Inverse Modelling and Void Cluster Analysis', Transport in Porous Media, vol. 124, no. 2, pp. 631-653. https://doi.org/10.1007/s11242-018-1087-1,

If your first language is not English, you will need to meet the minimum English requirements for the programme, IELTS Academic score of 6.5 (with no less than 5.5 in each component test area) or equivalent.  

Successful candidates who meet UKRI’s eligibility criteria will be awarded a fully-funded ARIES studentship of fees, maintenance stipend, £20,780 p.a. for 2025/26 (2026/27 rate TBC) and research costs. 

A limited number of ARIES studentships are available to International applicants. Please note however that ARIES funding does not cover additional costs associated with relocation to, and living in, the UK.

NB: The studentship is supported for 3.5 years of the four-year registration period. The subsequent 6 months of registration is a self-funded ‘writing-up’ period. 

ARIES is committed to equality, diversity, widening participation and inclusion in all areas of its operation. We encourage applications from all sections of the community regardless of gender, ethnicity, disability, age, sexual orientation, and transgender status. Projects have been developed with consideration of a safe, inclusive, and appropriate research and fieldwork environment. Academic qualifications are considered alongside non-academic experience, with equal weighting given to experience and potential. 

For further information, please visit www.aries-dtp.ac.uk.

If you wish to discuss this project further informally, please contact  Dr Michelle Harris . 

Please see our apply for a postgraduate research programme page for a list of supporting documents to upload with your application. 

For more information on the admissions process generally, please visit our apply for a postgraduate research programme page or contact the Doctoral College .

Shortlisted candidates will be invited for interview after the deadline. We regret that we may not be able to respond to all applications. Applicants who have not received a response within six weeks of the closing date should consider their application has been unsuccessful on this occasion.