Investigation of caprock integrity due to pressure build-up during high-volume injection into the Utsira formation

Abstract

In this work, we investigate the pressure-limited storage capacity of the Utsira formation. We employ the use of a simple capacity estimate based on maximum sustainable pressure. Here, the pressure during injection or post-injection cannot exceed the least compressive stress at the base of the caprock at any location. Given the global capacity estimate, large-scale simulations are performed to determine if the global capacity can be reasonably attained given local injectivity constraints and long-term CO2 trapping. We find that the Utsira can withstand injection rates over 100 Mt/y for 50 years, which is equivalent to 8.3 Gt of CO2.