4-D Stratigraphic Inversion of the Girassol Field – Towards a More Quantitative Approach

C018 4-D STRATIGRAPHIC INVERSION OF THE GIRASSOL FIELD - TOWARDS A MORE QUANTITATIVE APPROACH Summary 1 As applications of 4-D seismic technology become more mature there is a growing need for quantitative 4-D inversion workflows where base and monitor surveys are jointly inverted to estimate time-lapse changes in elastic properties which are then linked to changes in reservoir pressure and fluid saturation. In practice quantitative 4-D elastic inversion is made difficult by the presence of time-variant misalignments between corresponding seismic reflections in base and monitor surveys. These time-shifts are often the result of production-related velocity changes within the reservoir interval.