Time-lapse inversion and geomechanical modelling of the South Arne field

Time-lapse seismic technology is routinely used to monitor production-related reservoir changes. Indeed, the analysis of observed seismic 4D effects and estimation of the corresponding elastic attributes provide valuable information about the dynamics of the reservoir (saturation, pore pressure), particularly away from existing wells, into areas where production data is ‘blind.’ However, the interpretation of time-lapse response can be complex as different reservoir property changes can lead to the same variation in a given elastic parameter. This is particularly true for chalk fields undergoing porosity reduction in addition to change in fluid and pore pressure depletion.