This dataset contains geophysical, transport, and chemical data from a one-year experimental study on H2 and CO2-brine-rock interactions. Conducted under realistic stress conditions, the study replicates shallow saline aquifers in the Endurance area of the UK Southern North Sea - a primary target for carbon capture and storage (CCS) (BEIS, 2022). The primary objective was to differentiate the geophysical footprints of H2 and CO2 injections to improve underground storage monitoring. Fluid substitution tests accounted for coupled hydro-mechanical-chemical phenomena within the sandstone reservoirs. Medium- and long-term effects were assessed by combining monthly brine-gas flow-through tests with a six-month rock-gas-fluid exposure period, interspersed with hydromechanical, chemical, and transport analyses.
Three cylindrical core plugs were prepared from a drill core from well 48/06B7 at approximately 1,380 metres below sea floor, representing the potential injection depth for Endurance. The three samples are from the Bunter Sandstone Formation and comprise fine- to medium-grained red-brown sandstone. Samples were provided by the British Geological Survey (BGS) National Geological Repository (NGR) Core Store, the samples are designated based on their experimental fluid exposure:
- S-H2 (Loan Number: Core 290670; Ref ID: IS(M)913; Sample SSK151413 / 4530.83’–4531’; Date of Sampling: 03/03/2023; Return Date: 30/06/2025): Used for H2 flow-through testing.
- S-CO2 (Loan Number: Core 290670; Ref ID: IS(M)913; Sample SSK151412 / 4530.67’–4530.83’; Date of Sampling: 03/03/2023; Return Date: 30/06/2025): Used for CO2 flow-through testing.
- S-brine (Loan Number: Core 290552; Ref ID: IS(M)1364; Sample SSK150980 / 4530’5’’–4530’7’’; Date of Sampling: 20/01/2023; Return Date: 30/06/2025): Used for baseline brine flow-through testing. X-ray diffraction analysis was conducted at the BGS facilities.
Fluid substitution tests, elastic-transport assessments, batch tests, and pore fluid analyses were performed at 20°C in a specialized multi-flow-through setup at the Rock Physics Laboratory, National Oceanography Centre Southampton (NOCS). The experiments spanned 2022 to 2024 under the MOET (NE/W005026/1), FOCUS (NE/X006271/1), EHMPRES (NE/X003248/1), and CHORUS (NE/X012751/1) projects.
References:
BEIS, 2022. Endurance storage development plan. Key knowledge document (NS051-SS-REP-000-00010), in: Department for Business, Energy and Industrial Strategy. (Ed.), p. 74.
Falcon-Suarez, I.H., Papageorgiou, G., Jin, Z., Muñoz-Ibáñez, A., Chapman, M., Best, A.I., 2020. CO2-brine substitution effects on ultrasonic wave propagation through sandstone with oblique fractures. Geophysical Research Letters 47, e2020GL088439.
McCann, C., Sothcott, J., 1992. Laboratory measurements of the seismic properties of sedimentary rocks. GSL, London, Special Publications 65, 285-297.
BGS IDA Loan: 290670 & 290552