According to the International Energy Agency (IEA), carbon capture storage (CCS) is needed in order to cut greenhouse gas emissions up to 20% by 2050 in an effort to limit global average temperature rise by no more than 2 °C.
In the large-scale deployment of CCS, carbon dioxide emissions from sources like fossil-fuel power plants and industrial facilities are gathered, compressed, taken to a storage site, and buried deep underground for permanent storage in geological formations.
Most commonly, deeply buried porous rocks are used as storage receptacles. Often used are unmineable coal seams, deep saline aquifers, and depleted oil and gas fields.
Last year, a National Research Council (NRC) report assessed that large-scale CCS might increase earthquake risk and deemed CCS an ineffective and potentially dangerous method for significantly reducing emissions.
However, David Bercovi, a professor of geophysics at Yale University, and Viktoriya Yarushina, a postdoctoral researcher, created a mathematical model that evaluates geophysical consequences of pumping carbon dioxide into underground porous mafic rock, the most common rock on the planet, at different rates. Scientists and researchers are still learning about mafic rock, and there are great uncertainties about their long-term use in CCS.
What Bercovi and Yarushina discovered is that if a delicate balance is struck so that reactions are keeping pace with the rate of carbon dioxide pumping, earthquakes might be avoided.
Experts agree that more engineering studies are needed to determine the connection between CCS and earthquake risk.