oa Effects of Fractures on CO2 Storage

Storage safety is mainly controlled by a number of physical trapping mechanisms including the cap rock's ability to retain the trapped CO2 over long periods of time. It is therefore Important to consider geological heterogeneities, and in particular the effects of faults and fractures when evaluating the long term behaviour of a storage system. Collecting fracture data, integrating this information in geo- and reservoir models, and performing CO2 plume flow simulations are challenging tasks and an important area of research. There are a number of CO2 EOR (enhanced oil recovery) projects as well as active and potential CO2 storage sites where there are data on fracture properties. Among these locations are Weyburn (Canada), Sprayberry (USA), Snøhvit (Norway), In Salah (Algeria), Teapot Dome (USA). This data is of variable quality and needs to be reviewed and put into context for the purpose of CO2 storage. In this poster we compile this fracture data, compare the quality and usability for CO2 storage predictions, and evaluate the potential influence on the long term storage behaviour. Furthermore, we compare this data with our recent work on fracture characterization at the In Salah CO2 storage project. This work includes building of discrete fracture models and compositional fluid flow simulations. We will show that we needed to include fracture properties in our reservoir models to be able to explain the short term development of the CO2 plume 1-2 years after injection. This is a strong indication for the even stronger importance of appropriate fracture treatment for long-term simulations.