This project seeks to improve current methods of time-lapse seismic reflection modeling for carbon dioxide sequestration and miscible CO2 floods in oil and gas reservoirs and to develop new strategies to invert such data to estimate changes in pressure and CO2 saturation over time. The three major objectives of this DOE/NETL research project are to: ? Research and develop improved methods to quantitatively model the rock physics effects of CO2 injection in porous reservoir/aquifer rock systems. ? Develop a means to quantitatively model the seismic response to CO2 injection from well logs (1-D) and from digital earth model volumes (3-D and 4-D). ? Research and develop new technology to perform quantitative inversions of time-lapse 4-D seismic data to estimate injected CO2 distributions and pore pressure changes within subsurface reservoirs and aquifers.