Fig. 5: Uncertainties in river profile restoration.

a Calculated subsidence during burial of pre-Pliocene sediments using compaction parameters of shale, sand, and shaly-sand. Calculated deflection due to unloading of post-Messinian sediments using elastic thickness Te = 20, 30, 40, and 50 km. b Restoration based on the assumption that pre-Pliocene sediments are mostly shales (same as Fig. 4a). c Restoration based on the assumption that pre-Pliocene sediments are mostly shaly sand. The difference between b and c is 100 m in the sea level restoration (650 m versus 750 m, respectively).