In time lapse (4D) seismic studies, the impact of effective stress on the dry rock frame is difficult to constrain. The relationship between rock moduli and effective stress is dependent on rock properties, initial effective stress and the change in effective stress with time. A workflow is outlined to: 1) constrain laboratory and analogue data where significant variability is observed through use of well data; 2) provide initial effective stress and a time sensitive effective stress taking in to account the effects of pore pressure-stress coupling, where the stress state is not extensional. A time lapse feasibility case study in the Taranaki Basin, New Zealand is shown to demonstrate the sensitivity of these parameters, and indicate how uncertainties in bulk moduli and effective stress can then be quantified in the amplitude domain through modelling.

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