Towards a more Realistic Cap-rock Leakage Model

In this paper we present a model for capillary leakage that incorporates hysteresis in the modelling of hydrocarbon relative permeability in cap-rocks. The model captures the experimental behaviour observed in laboratory test on capillary leakage in synthetic trap models, Vassenden et al. (2003). In our model the hydrocarbon column height reaches the snap off height when the supply of hydrocarbons have stopped. We compare this model with another leakage model and concludes that the new model fits better with the experimental results. Thus the models differ in the imbibition process. A consequence is that hydrocarbons in place in the trap differs significantly between the two models; which will be of concern in basin modelling exploration.