Microscale porosity models as powerful tools to analyze hydrocarbon production mechanisms in liquid shale

Abstract Hydrocarbon production from liquid shale plays presents numerous challenges to modeling and understanding, specifically due to heterogeneity and low permeability. With the aid of the recent advances in high resolution characterization techniques, the current work proposes a partitioning scheme to divide porous media in shale into three different sub-media (porosity systems): inorganic matter and kerogen (in the shale matrix), along with fracture network (natural or hydraulic). A significant advantage of the presented model is its flexibility to incorporate different petrophysical and geological properties to each sub-media. Such capability extends the applicability of our approach to almost all carbon rich mudrocks with different levels of heterogeneity. Various production scenarios were then simulated to evaluate performance of the model. Although a very rich source of hydrocarbon, our results show that relatively high capillary pressure and very low rock permeability hinder oil production in organic-rich shale. Additionally, excessive pressure drop in the near fracture region and localized large gas to oil mobility ratio was observed to impact oil production rate.