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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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International audienceHere, the larger foraminifera found in Middle Eocene-Early Miocene rocks from Dhofar (Oman) and Socotra Island (Yemen) are studied in detail. The architectural analysis leads to the description of five new genera and nine new species: five agglutinated foraminifera, Pseudolituonella robineti n. sp., Socotraella ashawqi n. gen. n. sp., Pseudoaccordiella ayaki n. gen. n. sp., Barattolites andhuri n. sp., and Rogerella aydimi n. gen. n. sp.; and four porcellaneous foraminifera, Idalina grelaudae n. sp., Idalina pignattii n. sp., Macetadiscus incolumnatus n. gen. n. sp., and Omanodiscus tenuissimus n. gen. n. sp. The larger foraminifera identified in a composite section located in western Dhofar, in the Shuwaymiyah section located in eastern Dhofar, and in the Wadi Ayak section located on Socotra Island have facilitated the identification of the following larger foraminifera zones: SBZ 14–SBZ 15 (middle Lutetian), SBZ 16 (late Lutetian), SBZ 17 (Bartonian), SBZ 18 (latest Bartonian-earliest Priabonian), SBZ 19–SBZ 20 (Priabonian), SB 21–SB 22A (Rupelian), SB 22B–SB 23 (Chattian), and SB 24 (Aquitanian). All these data permit to assess the age of the following lithostratigraphic units: Dammam Fm.—Andhur Mb. lower Lutetian?-middle Lutetian age (SBZ 13?–SBZ 14 partim), Qara Mb. middle Lutetian (SBZ 14–SBZ 15), and Uyun Mb. upper Lutetian (SBZ 16); Aydim Fm.—Heiron Mb. Bartonian (SBZ 17), Moosak Mb. upper Bartonian-Priabonian (SBZ 18–SBZ 20), Tagut Mb. Priabonian (SBZ 19–SBZ 20), and Haluf Mb. Priabonian (SBZ 19–SBZ 20) to lower Rupelian (SBZ 21) on Socotra Island; Ashawq Fm. Rupelian (SB 21–SB 22A); and Mughsayl Fm. Chattian-Aquitanian (SB 23–SB 24)

Piggyback basins often display asymmetric sedimentary successions influenced by both regional and local syn-depositional tectonic structures. There are few examples where a complete exhumed piggyback basin fill can be analyzed, from proximal, close to source areas, to the distal deep-water sinks. The study of these basins is key to extract the stratigraphic signal of intrabasinal tectonics, which often competes and can even overprint other controlling factors such as eustasy, climate, or autogenic processes. The purpose of this paper is to propose a more detailed model of the evolution of piggyback basin fills, which recognizes the influence of intrabasinal tectonic activity, specific to the piggyback context and the resulting stratigraphic architecture. We investigate the Tremp-Graus-Ainsa piggyback basin, located in the southern Pyrenees, during early