Improved particle tracking proxy for assessing plume migration during geologic sequestration

During geologic carbon sequestration, it is of immense importance that the migration of the injected plume of CO₂ be monitored in order to ensure containment within the storage volume. We have previously described a framework for predicting future plume migration, taking into account routinely recorded well data (like injection rate or bottom-hole pressures). The cornerstone of our prediction process is the use of a particle-tracking proxy that provides the ability to assess rapidly the flow connectivity of multiple aquifer models without the need to use computationally expensive numerical simulators. In this paper, we extend the proxy to explicitly represent multiphase flow effects, buoyancy effects and the effect of fluid viscosity and compressibility. The resultant proxy is thus robust for representing plume migration corresponding to flow and transport of CO₂ in aquifers exhibiting complex heterogeneity and for different physical flow and transport mechanisms.