Patent ID: 7242637

Claim:
A method of investigating a reservoir region in a subsurface formation using a time-lapse seismic survey, wherein said subsurface formation comprises a further formation region adjacent to the reservoir region, said method comprising the steps of: obtaining data from a time-lapse seismic survey from a source and receiver, including seismic data of the subsurface formation at a first point in time and a later point in time; processing the seismic data to obtain a seismic representation of change in a predetermined seismic parameter in the further formation region, said seismic parameter being dependent on stress in the further formation; interpreting the seismic representation of change in the seismic parameter in the further formation region for an indication of changes of stress distribution in the further formation region caused by a change in a property of the reservoir region; deriving the change in the property of the reservoir region from the indication of change of stress distribution in the further formation region; and storing or displaying the change in the property of the reservoir region.