A key challenge in large-scale carbon dioxide (CO2) sequestration is that injecting large amounts of CO2 pressurizes the subsurface. This pressurization is one fundamental limit on reservoir capacity because of the risk of reservoir damage and leakage. A new study by Kyung Won Chang and colleagues at the University of Texas at Austin will help to clarify this limitation. They study the role of pressure dissipation through the low-permeability layers that surround the injection reservoir. They focus on an idealized scenario and explore a wide range of parameters, showing that this dissipation can in many cases greatly decrease the extent of the pressurized region and lead to larger storage capacity.
K. W. Chang, M. A. Hesse, and J.-P. Nicot. Reduction in lateral pressure propagation due to dissipation into ambient mudrocks during geological carbon dioxide storage. Water Resources Research, 49(5):2573-2588, 2013. (http://dx.doi.org/10.1002/wrcr.20197)