Patent ID: 8908474

Claim:
A method for inversion of time-lapse (4D) seismic data (a base survey and a later monitor survey of the same subsurface formation) to estimate the change in fluid saturation and reservoir pressure from the time of the base survey to the time of the monitor survey, comprising: (a) at at least one well location, inverting the 4D seismic data in a single iterative inversion process to directly obtain formation pressure change and fluid saturation change versus for at least one formation fluid, constraining the inversion with well log data, wherein the inversion is model-based and incorporates rock physics in the model, and the model is a 1D model showing variation as a function of depth; and (b) using the saturation and pressure change from at least one well location to obtain saturation and pressure change away from well locations, thereby generating a well-tied fluid saturation and pressure change model predicting change of fluid saturation from the time of the base survey to the time of the monitor survey.