Screening offshore geological structures for implementing a CO2 injection pilot in Portugal

Abstract

This study evaluates potential offshore geological structures for a CO2 injection pilot in Portugal, focusing on the Lusitanian Basin as part of the PilotSTRATEGY project funded by the European Commission. The Lusitanian Basin, located on the Western Iberian Margin, offers significant potential for CO2 storage within its deep saline aquifers (DSA). The northern sector of this basin was selected for detailed studies due to its comprehensive geophysical data coverage and proximity to industrial CO2 sources. The research utilized well-log data, 3D seismic volumes, and 2D seismic profiles to characterize potential storage sites, identifying the Lower Cretaceous and Upper Jurassic formations as promising reservoirs. The primary seals are composed of Upper Cretaceous carbonate-rich rocks, while secondary seals include Paleocene siliciclastic deposits and dolomites. Structural and stratigraphic interpretations were performed to identify potential storage sites and assess their capacity to maintain CO2 in a supercritical state. The application of quantitative seismic interpretation techniques, alongside petrophysical data, is planned for future work to enhance prospect characterization and support a detailed risk analysis. This study underscores the Lusitanian Basin's capacity for CO2 storage, contributing to Portugal's carbon management strategies.