This PhD project at Heriot-Watt University investigates the synergistic and competitive effects between multiple gas storage operations in subsurface porous media, with a particular focus on the North Sea region. As CO₂ storage projects proliferate and interest in subsurface hydrogen storage grows, understanding the interactions between different injection sites and gas types becomes critical for safe, efficient, and sustainable geological resource management. The research aims to explore fluid migration behaviour and pressure dynamics when CO₂, H₂, and natural gas storage processes coexist in close proximity, examining both competitive and synergistic interactions. The project will employ advanced flow simulations using industry-standard software such as CMG, ECLIPSE, PFLOTRAN-OGS, and research codes like MATLAB to model these complex subsurface processes. The outcomes will inform strategic resource use, capacity planning, and pressure management, contributing to responsible stewardship of geological formations increasingly used for energy storage. The position is based in the School of Energy, Geoscience, Infrastructure and Society and is supported by a full EPSRC scholarship for UK-home students, including tuition fees and a generous annual stipend (£20,780) for 42 months, with additional funding from Crown Estate Scotland for research and travel. Applicants should have a strong background in geoscience, geology, earth science, or engineering, and must provide a comprehensive application including a supporting statement, CV, academic transcripts, reference, and proof of English proficiency. The application deadline is November 28, 2025, with a start date in January 2026. For further information or informal discussion, candidates are encouraged to contact the supervisory team.

This PhD project at Heriot-Watt University, in collaboration with the University of Glasgow, the University of Edinburgh, and Pacific NorthWest National Lab, focuses on reactive fracturing and carbonation dynamics in mafic and ultramafic rocks under CO₂ storage conditions. The research aims to advance understanding of how carbonate mineralisation and crystallisation-induced stress drive fracture evolution and permeability changes in basaltic systems exposed to CO₂-rich fluids. The project integrates geomechanics, geophysics, geochemistry, and advanced imaging techniques such as X-ray micro-computed tomography (µCT) and acoustic emission (AE) monitoring to visualise and quantify fracture growth, mineral precipitation, and microcracking in real time. Key research questions include: the influence of crystallisation-induced stress on fracture propagation, the coupled geochemical and mechanical controls on carbonation in basalt, and the integration of µCT and AE monitoring to model reactive fracturing processes. The project will also explore the potential of mafic rock carbonation for critical mineral liberation. Laboratory experiments will be conducted under realistic pressure, temperature, and stress conditions, with a reactive transport modelling framework developed to link observed geochemical gradients with mechanical effects. The methodology involves specimen preparation, baseline characterisation, CO₂–fluid reaction experiments, in-situ monitoring, post-experiment multi-scale characterisation, image-based mechanics, and reactive transport modelling. The project timeline spans imaging workflow, AE monitoring, pilot experiments, advanced microCT, geochemical analyses, reactive transport modelling, and integration of lab tests with modelling for upscaling to reservoir-relevant metrics. Applicants should have a strong background in geoscience, geomechanics, geophysics, geochemistry, or related fields, with experience in laboratory experiments and imaging techniques being desirable. The position is open to UK-based students only at this stage and is part of the IAPETUS Doctoral Training Partnership, which typically provides full funding including tuition and stipend. The application deadline is January 5th, 2025. For more information or informal enquiries, contact Prof. Andreas Busch at [email protected]. Keywords: reactive fracturing, mafic rocks, geomechanics, geophysics, geochemistry, imaging, CO2 storage, basalt, mineralisation, acoustic emission, microCT, hydrothermal experiments.