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This work presents the first results of recent efforts in modeling 4D seismic signals related to geomechanical effects in a pre-salt carbonate field, caused by reservoir production-induced rock properties changes in the reservoir and the overburden. The focus is to investigate the potential detectability of expected minute time-shifts in a stiff carbonate environment. Emphasis is placed on understanding the effect of the behavior of the salt-layer directly above the reservoir on the expected timeshifts. We examine the mechanical response of salt to production of the underlying reservoir, and how this mechanical response may affect observable time-lapse timeshifts.We ask and answer two distinct questions from 3D geomechanical simulations during different stages of reservoir production into and calculation of 4D seismic travel-time differences. The first question assesses the robustness of 1D cross-correlation to measure sub-sample time-shifts. We first create a monitor survey by warping 3D seismic field data using traveltime differences derived from 3D geomechanical modelling, followed by application of a strain-sensitive rock-physics model. The maximum simulated timeshifts are approximately 0.2 to 0.3 ms at the top of the reservoir under the assumption of vertical wave propagation. We use the warped dataset and the original field dataset to measure the (known) timeshifts. We show that timeshifts of this magnitude can be measured in the presence of realistic amounts of coherent and random noise. The second question concerns the ability to measure time-lapse timeshifts after shot-receiver records went through a seismic processing sequence. Base-and monitor seismic data are generated from seismic velocity models using an ocean-bottom node (OBN) survey geometry. The velocity model for the monitor survey is again perturbed by the strain-induced velocity changes and both data are migrated using a least-squares reverse time migration (LSRTM). Time-lapse timeshifts are then analyzed from the final migrated images of the base-and monitor surveys.The geomechanical response of the salt layer to production from pre-salt reservoirs is still poorly understood. We therefore geomechanically simulate two end-members, whereby (i) salt behaves elastically and can maintain differential stress over production time-scales and (ii) differential stress in salt is small, resulting in a near isotropic stress state inside salt. The two different scenarios of salt behavior cause a marked difference in the post-production stress fields and a distinct response in terms of magnitude and shape of 4D time-shift anomalies. This means that the ability of monitoring seismic velocity changes in the overburden may result in an indication of how salt layers behave over production time, and map regions where stresses and strains create a risk to wellbore integrity and to fault reactivation.