THE DEVELOPMENT OF A REGIME-BASED FRAMEWORK FOR THE ANALYSIS OF WETTABILITY EXPERIMENTS

This paper examines the macroscopic consequences of wettability variat ions at the pore-scale. Important theoretical issues relating to distr ibuted contact angles are examined and a process simulator capable of simulating the full flooding cycle characteristic of laboratory wettab ility tests is described. Simulations predict that final waterflood re coveries from weakly water-wet, or even weakly oil-wet, systems can of ten exceed those from strongly water-wet systems-even though initial i mbibition rates may lead to the opposite conclusion. The underlying po re level physics has been explored by defining a capillarity surface w hich incorporates the combined effects of both contact angle and pore dimension during the imbibition process. Finally, a regime-based frame work has been developed which can be used to reconcile apparently cont radictory wettability experiments.