Visualisation of multiphase fluid displacement at pore scale in carbonate media using X-ray microtomography

The application of high resolution x-ray computed tomography in conjunction with x-ray transparent core holders and representative volumes of porous carbonate media enable exceptionally high quality imaging of fluid displacement processes. The experiments show that the rock is water wet. This in turn is in agreement with what was expected prior to running the experiments since the rock was a clean outcrop and has never been exposed to hydrocarbon phases. Moreover, major fluid displacement mechanisms being used in pore scale simulations including piston like displacement and snap off have been captured clearly. The experiments have characterized the transport features and the structure of residual oil present in a water wet system. Subsequent experiments will focus on wettability alteration to develop oil wet surfaces for direct comparison. The on-going phase of this study will focus on building multiple scale network models and using them to run fluid displacement simulations. These models will be validated against experimental data such as MICP and relative permeability measurements.