Abstract This paper examines the stratal geometries and facies stacking patterns associated with forced regressions around fault-propagation folds in extensional and compressional settings. Case studies are documented from: (i) the Miocene of the Suez rift and (ii) the Eocene of the Ainsa piggyback basin, Pyrenees. Despite the different tectonic settings, the stratal geometries and facies stacking patterns are remarkably similar. Distinctive sharp-based shoreface sandstones, formed as a result of forced regression, were deposited around growth anticlines. The forced regressive shoreface sandstones ‘shale-out’ rapidly basinward away from the growth anticlines and sit abruptly within offshore mudstones of highstand (HST) and transgressive (TST) systems tracts along the flanks of the growth anticlines. As fold amplification proceeded, older sandbodies were rotated to dip more steeply, and there is commonly a 2–5° angular difference between successive forced regressive sandbodies. This progressive tilting, coupled with marine erosion during relative sea-level fall has completely removed HST and TST deposits near anticline crets, and led to vertical amalgamation of individual forced regressive sandbodies. The resulting stratal geometries clearly result from the tectonic enhancement of forced regression.

Abstract Late Quaternary depositional sequences in northern Peloponnesos, central Greece, occur as a number of offlapping and downstepping forced regressive wedges. Major along-strike variability is evident, with three environmental responses to forced regression: (i) attached shoreface deposits; (ii) detached shoreface deposits; (iii) fan-deltas. All three depositional systems are cut by incised valleys. Relative sea-level change was responsible for similarities in key stratal surfaces and stacking patterns; regional uplift drove the overall forced regression, whereas individual sequences relate to fourth- and fifth order glacioeustatic cycles. Variations in basin physiography and the amount and type of sediment led to along-strike variability of depositional sequences. Fan-deltas developed at the mouths of incised valleys in the west of the area, where supply of coarse-grained sediment was high and slope gradients were steep. In contrast, limited supply of coarse-grained sediment and low slope gradients over most of the study area promoted the development of shoreface systems. Forced regressive wedges in the shoreface systems attach and detach along strike. Detached wedges developed where both slope gradients and coarse-grained sediment supply were low, away from the axes of major incised valleys.