P‐wave attenuation as an additional tool for monitoring CO 2 injection sites

Changes in P‐wave attenuation are successfully measured from a CO2 sequestration injection site. Simple but accurate measurements of attenuation from pre and post injection VSPs demonstrate the capability to detect small changes in intrinsic attenuation in the presence of large scattering attenuation (frequency dependent noise). The frequency dependent noise is shown to be very repeatable between vintages and the increase in attenuation in the injection zone can be associated with an increase in CO2 concentration. We show that seismic attenuation has the potential to be a useful additional tool for monitoring CO2 sequestration.