Comparison of geological models for the simulation of CO2 migration: a case study in Ordos, China

At the deep saline‐aquifer level, geological storage of CO2 is considered to be one of the most effective geological methods for reducing greenhouse gas concentrations and emissions. The objective of this study is to compare the performance of different geological models in simulating CO2 storage as part of the Ordos Shenhua project, which is the first and the largest demonstration project in China. The project has injected 300 000 t of CO2 into low‐permeability saline aquifers at a depth of 1600 m. The injection procedure began in May 2011 and ended in April 2015. We studied the impact of different models on the predicted gas saturation distribution of the CO2 plume 50 years after well shutoff, using the CO2STORE module in the Eclipse E300 simulator. In our simulation comparisons, four 3D geological models are established, including the flat constant model, flat sequential Gaussian model, seismic constant model, and seismic sequential Gaussian model. The seismic sequential Gaussian model is the most precise model, which is established through the sequential Gaussian co‐simulation method under the constraints of the seismic profile. Actual monitoring data were applied for historical pressure fitting in the four different geological models. Through the comparison of the four models, it can be concluded that the seismic sequential Gaussian model simulated CO2 migration more effectively. The results of this project can provide support for safety assessments in the later stages of deep monitoring programs. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd.