Providing clean energy for the UK: testing the efficacy of Carbon Capture and Storage (CCS) in the North Sea

In this fellowship the integrity of the overburden stratigraphy above the primary seal of potential CCS reservoirs in the North Sea will be investigated. It has become increasingly clear that new sources of renewable energy will be insufficient for helping the British government to achieve their greenhouse gas (GHG) emissions targets. In order to accomplish the 2050 target of an 80% reduction of CO2 emissions it is likely that Carbon Capture and Storage (CCS) will have to play an integral part of any low-carbon energy portfolio. The ideal location for any CCS generation is going to be proximal to existing reservoirs, such as those in the North Sea, which have been depleted of oil and gas. Thus, the prolific success of the oil and gas industry in the North Sea means that there is significant potential for using this infrastructure for CCS. However, the current state of knowledge on the efficacy of a CCS scheme in the North Sea is poorly-known and there remains an important lack of detail on the quantification of risk that would be associated with such a scheme. By using seismic reflection data to characterise these poorly-known sediments and any geomorphological features that they contain (e.g. tunnel valleys, iceberg scours, fluvial channels, sandstone intrusions, chimneys, and pipes) potential routes for rapid vertical and lateral gas and fluid flow will be mapped. Seismic attributes will be combined with abundant subsurface data from wells in the North Sea to populate this better-constrained stratigraphy with quantitative rock properties. This data will then be used to produce a 3D model where the potential CCS reservoir will be filled until saturated with CO2. This model, which represents an approximation to reality, will allow for overburden leakage to be assessed and, more broadly, for the efficacy of the study area as a potential CCS site in the North Sea to be tested. The main conclusions from this project will lead to a better understanding of the potential and application for CCS in the North Sea. It is also anticipated that the overburden characterisation will provide additional palaeo-climatological information on past environmental changes that will be of use to climate modellers.