Tom Lynch

Graduated with an interdisciplinary MSc/PhD in the Doctoral Training Centre for Low Carbon Technologies

Thesis: Geological Storage of Carbon Dioxide in the UK: Opportunities and Risks

Carbon Capture and Storage (CCS) offers one of the most promising ways to reduce CO2 emissions from large CO2 point sources, such as fossil fuel power stations. Storage of CO2 is most likely to be in the geosphere in depleted petroleum reservoirs and deep saline formations. However, there remains significant uncertainty in estimates of total storage capacity, potential injection rates, and leakage pathways and rates.

Dr Tom Lynch’s PhD project used coupled and non-coupled flow and geomechanical models to investigate potential storage capacities, injection rates and leakage mechanisms within proposed geological storage sites both onshore and offshore UK. Novel outcomes of the work included: modelling of hysteretic behaviour of the fracture pressure for storage in depleted hydrocarbon reservoirs, which may indicate lower fracture pressures than expected during injection of CO2; modelling of the variability in capacity estimates in the Bunter Saline Aquifer based on geological variability; and identification of very long term pressure lag effects in the aquifer which may have implications for monitoring and remediation of CO2 injection in the aquifer over significant spatial and temporal scales.

Tom’s post-doc continues work in this area, using the same numerical modelling techniques, but with a greater focus on the behaviour of the caprock seal to geological CO2 storage units. Using a combination of laboratory investigations and numerical modelling incorporating laboratory data he will investigate fracture closure behaviour in shale cap-rocks and the effect of CO2 temperature on reservoir and caprock fracturing.