CO2 migration in saline aquifers. Part 1. Capillary trapping under slope and groundwater flow

CW MacMinn, ML Szulczewski and R Juanes, Journal of Fluid Mechanics, 662:329-351, 2010. doi:10.1017/S0022112010003319

When CO2 is injected into a saline aquifer for carbon sequestration, it will rise and spread due to buoyancy. It will also migrate away from the injection well if the aqufier is sloped, or due to background (regional) groundwater flow through the aquifer. As the CO2 migrates, small blobs of residual CO2 are left behind in the pore space of the rock -- this process is known as residual or capillary trapping.

Here, we presented a theoretical model to study the interaction between migration and capillary trapping in a large-scale plume of CO2. We developed a complete analytical solution to the model in its hyperbolic limit. These solutions are very useful, but can be quite tricky to implement because they involve many different cases (see the paper), so we're providing a complete MATLAB implementation of the full solution:

Note that a few of the functions require the Symbolic Math toolbox.