CO2 Sequestration and 4-D Seismic

1. Towards tracking the movement of CO2 plumes in carbon storage reservoirs using time-lapse seismic monitoring (where, 3-D seismic surveys are taken over various time levels @ same location), to what extent, the time-lapse values of the measured seismic properties including seismic velocity, travel time & reflection amplitude would be able to precisely reflect the variations in the elasticity of the reservoir?

2. Could such variations be confidently related to changes in reservoir properties including pore pressure and CO2 saturation?

3. How about the magnitude of seismic responses to scCO2 and its associated seismic noise level?

4. If the reservoir remains to be highly consolidated (as the depth exceeds 800 m in case of super critical CO2 injection), how about the quality of 4-D seismic signal (where, the rock-matrix remains to be relatively lesser compressible, while, the contrast between scCO2 and the in-situ brine also not remaining larger)?

5. Seismic inversion being an ill-posed and highly non-linear problem, can we go ahead with geophysical inversion with minimal recorded data?

6. Feasible to get rid-off rescaling issues completely by coupling static and dynamic loop methods towards reservoir characterization using Bayesian 4-D seismic inversion?

7. Feasible to continuously collect wavelet as well as seismic amplitude from 4-D seismic surveys towards monitoring seismic wave attenuation caused by seismic wave energy attenuation (and by wave-front diffusion)?

Dr Suresh Kumar Govindarajan

Professor [HAG] IIT Madras 25-Jan-2025