Mike Curtis, Managing Director, CASP

The Lower to Middle Triassic Bunter Sandstone Formation represents the primary CO2 storage reservoir in the Southern North Sea and will play an integral role in the UK’s Net Zero Strategy. It is the main interval of interest for the Endurance structure (UK Blocks 42/25 and 43/21; Figure 1), one of two CO2 storage sites selected by the UK Government for initial development, and is central to the North Sea Transition Authority’s first carbon storage licensing round. A thorough understanding of the Bunter Sandstone storage complex’s composition, correlation and timing of deposition, as well as how the reservoir and seal will behave when subjected to the injection of CO2 is essential.

Figure 1. Palaeogeographic map for the Lower to Middle Triassic showing approximate spatial extent of each of the research theme's projects alongside CO2 storage license blocks and proposed wells to be sampled. Modified from Geluk et al. (2018).

The first phase of projects within this research theme will be based on a newly available cored section from an onshore borehole in North Yorkshire, as well as core and cuttings from selected wells of the Southern North Sea (UK and Dutch sectors). A palynostratigraphy and cyclostratigraphy will be established that will enable the correlation of strata across the basin and provide a framework for compositional and provenance studies, as well as an assessment of regional seal units.

Together these projects will better inform the assessment of Lower to Middle Triassic strata in the Southern North Sea for CO2 storage. Futher research is anticipated to model the impact of composition variability on CO2 reactivity and reservoir efficiency, as well as modelling of seal performance in the Bacton and Haisborough groups, using the data generated by these projects.

KeyFacts Energy Industry Directory: CASP