Leveraging Analogues for CO2 Core Flood Experiments: Enhancing Reservoir Simulation Inputs

Carbon capture and storage (CCS) initiatives rely on robust CO₂ core flood experiments to clarifytransport and trapping mechanisms within geological formations. However, a paucity of reservoir-conditionexperimental data often hampers the direct application of field core results for reservoir simulation. Thispaper emphasizes the critical need for analogues in CO₂ core flood experiments, especially in areas wheresuch data remain sparse. Steady-state drainage relative permeability measurements were conducted atrepresentative reservoir conditions, using equilibrated CO₂ and synthetic formation water (SFW) onreservoir core samples. These measurements were complemented by 1D X-ray scanning of average watersaturations and differential pressures, followed by history matching (HM) to validate experimentalobservations. X-ray diffraction (XRD) analyses revealed that calcite concentrations ranged from 5% to 30%in the studied reservoir rocks. An automatic history-matching approach, employing a specialized core floodsimulator, was utilized to estimate key parameters. Compositional simulation further assessed the impact ofdifferential pressure, carbonate dissolution, and CO₂ dissolution on phase-property variations. Minorgeochemical effects were observed, attributable to the relatively high brine salinity and low differentialpressures. Consequently, chemical reactions were deemed negligible for history matching under theconditions studied. Further validation included the integration of capillary pressure data measured viaMercury Intrusion Capillary Pressure (MICP). The MICP-derived capillary pressures correlated closely withthe estimated values across the experimentally relevant saturation range, indicating that any potentialwettability shifts were either minor or negligible. This consistency supports MICP-based capillary pressureas a sound proxy for the CO₂/brine system under reservoir conditions. From these analogue-drivenexperimental outcomes, a comprehensive SCAL model—including an uncertainty range—was developedand used to inform subsequent reservoir simulations. This model is essential for refining our understandingof CO₂ storage potential on the Norwegian Continental Shelf (NCS), and the results were benchmarkedagainst existing data from the Northern Lights project. By highlighting the advantages of analogues, thisstudy encourages their broader use in CO₂ core flood research, with the aim of improving CO₂ storagestrategies and enhancing the effectiveness of reservoir simulations.