Modelling of the flow of immiscible fluids through the pore network of a porous medium, for example during displacement of oil from a rock by water flooding, has been greatly aided by the advances in micro-computerised tomography, which can provide a 3D digital image of the physical structure of this network. However, flow models also require as input the contact angle of the fluid interface at the pore walls. The relatively modest success to date of network models in predicting oil recovery is partly due to the complexity of reservoir wettability, which typically varies spatially (even within individual pores) and can evolve over time (in response to fluid relocation). The presentation describes recent efforts at ANU to map the wettability distribution within rock pores, towards the ultimate goal of providing a unified 3D image of the physical pore network of a porous medium overlain with the local surface chemistry of its walls. Further, the intermolecular interactions between fluid and solid phases which give rise to the observed wettability and its variability are also discussed.

About the speaker

Andrew Fogden completed his PhD in applied mathematics at ANU, in the field of interfaces in soft condensed matter, after which he worked at universities and research institutes in Sweden, mainly focusing on solid-liquid interactions in printing processes. Since 2006 he has been employed as a Research Fellow at Applied Mathematics, working on understanding the mechanisms of oil recovery.