Interpretation and depth conversion of an extensive, well-calibrated seismic database provides the basis upon which to map the limits and evaluate the geological risks of using a saline aquifer target for carbon dioxide (CO2) storage in the Moray Firth Basin of the North Sea. The seismic interpretation demonstrates that the Lower Cretaceous (Albian-Aptian) Captain Sandstone Member is a continuous, interconnected reservoir that rises to subcrop in western areas of the basin as a consequence of Early Cenozoic uplift and tilt. As such, the aquifer forms an open system with few barriers or sizable closures to arrest or entrap light fluids and gases en route to its western subcrop. The new interpretation also shows that the saline aquifer is cut by several WSW-ENE striking reactivated normal faults. Whilst migration along the faults permitted hydrocarbons to get into structurally elevated traps, such as the Captain Field itself, some faults also breach the seal of the Captain Sandstone Member aquifer, rise to the sea-bed and increase the risk of seabed leakage. Consequently, despite its large storage capacity, the dip, subcrop and fault reactivation affecting the Captain Sandstone Member aquifer all suggest that its use of as a site for CO2 storage remains unproven and is not the best choice for an initial North Sea exemplar. As such, the study highlights the importance of undertaking a robust and forensic geological screening of any prospective storage site prior to injection.
|Number of pages||21|
|Early online date||20 Sept 2017|
|Publication status||Published - Nov 2017|
ASJC Scopus subject areas
- Sociology and Political Science