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We present and use the chronostratigraphy of 13 field logs and detailed mapping to constrain the evolution of the early Zagros foreland basin, in NW Iran. Large foraminifera, calcareous nannofossil, palynological and 87 Sr/ 86 Sr analysis supplied ages indicating a Campanian–early Eocene age of the basin infill, which is characterizd by a diachronous, southwestward migrating, shallowing upwards, mixed clastic–carbonate succession. Growth synclines and local palaeoslope variations indicate syndepositional folding from Maastrichtian to Eocene time and suggest forelandward migration of the deformation front. We also illustrate the basin architecture with a synthetic stratigraphic transect. From internal to external areas, time lines cross the formation boundaries from continental Kashkan red beds to Taleh Zang mixed clastic–carbonate platforms, Amiran slope deposits and basinal Gurpi–Pabdeh shales and marls. The foreland basin depocentres show a progressive migration from the Campanian to Eocene ( c . 83–52.7 Ma), with rates of c . 2.4 mm a −1 during the early–middle Palaeocene ( c . 65.5–58.7 Ma) increasing to c . 6 mm a −1 during the late Palaeocene–earliest Eocene ( c . 58.7–52.8 Ma). Coeval subsidence remained at c . 0.27 mm a −1 during the first 12.7 Ma and decreased to c . 0.16 mm a −1 during the last 4.2 Ma of basin filling. Finally, we integrate our results with published large-scale maps and discuss their implications in the context of the Zagros orogeny. Supplementary material: Tables with dating results are available at http://www.geolsoc.org.uk/SUP18439 .

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Local isostatic backstripping analysis is performed across the eastern part of the Ebro foreland basin between the Pyrenees and the Catalan Coastal Ranges. The subsidence analysis is based on two well-dated field-based sections and four oil-wells aligned parallel to the tectonic transport direction of the eastern Pyrenean orogen. The marine infill of the foreland basin is separated into four, third-order, transgressive-regressive depositional cycles. The first and second depositional cycles are located in the Ripoll piggy-back basin and the third and fourth ones are located south of the syn-depositional emergent Vallfogona thrust. Subsidence curves display a typical convex-up shape with inflection points recording the onset of rapid tectonic subsidence. Inflection points coincide roughly with the base of depositional cycles. Rates of tectonic subsidence are less than 0.1 mm a -1 in distal parts of the basin and up to 0.53 mm a -1 in proximal parts during second depositional cycle. Younger depositional cycles show maximum rates of tectonic subsidence of 0.26 mm a -1. The locus of subsidence within the basin migrated southward at a rate of c. 10 mm a -1. This flexural wave crossed the complete Ebro foreland basin in 10-11 Ma. The intraplate Catalan Coastal Ranges at the southeastern margin of the Ebro foreland basin produced an increase of tectonic subsidence rate at 41.5 Ma. Maximum rates of tectonic subsidence coincide with deep-marine infill of the basin, maximum rates of shortening and thrust front advance, and low topographic relief orogenic wedge. Transgressive-regressive depositional cycles can be controlled partly by reductions of available space within the basin during tectonic thickening of the sedimentary pile by layer parallel shortening, folding and thrusting.Although much less constrained, an approximation of post-thrusting exhumation and isostatic and tectonic uplift, as well as a first determination of possible amounts of eroded material of parts of the Ebro basin illustrate the impact of post-depositional erosion and uplift on the foreland.

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