We propose a new approach to update fault seal estimates in fluid flow simulation models by direct use of 4D seismic amplitudes calibrated by a well geological constraint. The method is suited to compartmentalized reservoirs and based on metrics created from differences in the 4D seismic signature on either side of major faults. The effectiveness of the approach is demonstrated by application to data from the fault controlled Heidrun field in the Norwegian Sea. The results of this application appear favourable and show that our method can detect variations of fault permeability along the major controlling faults in the field. Updates of the field simulation model with the 4D seismic-derived transmissibilities are observed to decrease the mismatch between the predicted and historical field production data in the majority of wells in our sector of interest.