Project Description
Supervisors
Dr Michelle Harris, School of Geography, Earth and Environmental Science, University of Plymouth
Dr Andy Parsons, School of Geography, Earth and Environmental Science, University of Plymouth
Dr Katie Jones, School of Geography, Earth and Environmental Science, University of Plymouth
Dr Giuliano Laudone, School of Geography, Earth and Environmental Science, University of Plymouth
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.
Research Methodology
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.
Training
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.
Person Specification
We seek a motivated individual with an interest in Earth Science and a desire to develop expertise in analytical techniques and modelling/basic programming.
Acceptable first degree subjects: Earth Sciences, Geology, Material Science
Project code: HARRIS_PLYM_ARIES26