Crude Oil–Brine–Rock Interactions in Tight Chalk Reservoirs: An Experimental Study

Samira Mohammadkhani*, Benaiah U. Anabaraonye, Armin Afrough, Rasoul Mokhtari, Karen Louise Feilberg*

*Corresponding author for this work

    Research output: Contribution to journalJournal articleResearchpeer-review

    74 Downloads (Pure)


    We present a systematic study of crude oil–brine–rock interactions in tight chalk cores at reservoir conditions. Flooding experiments are performed on outcrops (Stevns Klint) as well as on reservoir core plugs from Dan field, the Ekofisk and Tor formations. These studies are carried out in core plugs with reduced pore volumes, i.e., short core samples and aged with a dynamic ageing method. The method was evaluated by three different oil compositions. A series of synthetic multicomponent brines and designed fluid injection scenarios are investigated; injection flow rates are optimized to ensure that a capillary-dominant regime is maintained. Changes in brine compositions and fluid distribution in the core plugs are characterized using ion chromatography and X-ray computed tomography, respectively. First, we show that polar components in the oil phase play a major role in wettability alteration during ageing; this controls the oil production behavior. We also show that, compared to seawater, both formation water and ten-times-diluted seawater are better candidates for enhanced oil recovery in the Dan field. Finally, we show that the modified flow zone indicator, a measure of rock quality, is likely the main variable responsible for the higher oil recoveries observed in Tor core samples.
    Original languageEnglish
    Article number5360
    Issue number17
    Number of pages20
    Publication statusPublished - 2021


    • Low salinity water
    • Crude oil–brine–rock interactions
    • Chalk
    • Short core plug
    • Core flooding


    Dive into the research topics of 'Crude Oil–Brine–Rock Interactions in Tight Chalk Reservoirs: An Experimental Study'. Together they form a unique fingerprint.

    Cite this