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Nummulitic Limestones deposits are preserved along the tectonic contact between the Variscan basement and Alpine units of Corsica. These marine carbonates, dated from the Late Palaeocene to the Middle Eocene, were deposited within a foreland flexural basin that is considered to be the southern continuation of the Alpine foreland basin of southeast (SE) France. However, in contrast with the Nummulitic Limestones of SE France, those of Corsica are far less documented. This field‐based study constrains the sedimentology, stratigraphy and structure of the Nummulitic Limestones of Corsica in three localities (Balagne, Corte and Sari‐Solenzara) to identify factors that controlled foreland basin development and to clarify its significance within the early alpine orogen. The microfacies, microfaunal assemblages and siliciclastic fractions are characterised throughout the succession at each locality. The results indicate the existence of an important Variscan basement relief to the west of the basin (West Corsican Massif) that supplied early alluvial fans found at the base of the foreland succession in the northernmost Balagne area. Continuous high clastic input strongly reduced the development and diversity of the overlying Nummulitic Limestones facies and fauna. Further south, limestones in the Corte and Sari‐Solenzara areas are thicker and contain richer fauna. Three depositional models corresponding to the carbonate ramp system are proposed for the Nummulitic Limestones and used to construct paleogeographic maps illustrating the transgressive evolution of the Corsican foreland basin from the Early to the Late Eocene. Based on our results and available regional tectonic data and LT thermochronological data, we propose that the Nummulitic marine transgression took place within a continuous foreland basin encompassing southern Corsica and SE France during the early development of the western alpine arc. [ABSTRACT FROM AUTHOR]

We present new sedimentological, petrographical, palaeontological and detrital zircon U–Pb data on late Oligocene–early Miocene sedimentary rocks of the thin‐skinned thrust belt of East Carpathians. These data were acquired to reconstruct the sedimentary routing system for two compositionally different turbidite fans made of the regionally extensive Kliwa and Fusaru formations. On the eastern margin of the Moldavides foreland basin, large low‐gradient river systems draining the East European Platform provided well‐sorted quartz‐rich sand forming deltas on wide shallow shelves and thick Kliwa submarine fans. Due to the westward subduction of a thinned continental plate, the western basin margin was characterized by short, steep‐gradient routing systems where sediment transport to deep water was mainly through hyperpycnal flows. The Getic and Bucovinian nappes of the East Carpathians and the exhumed Cretaceous–Early Palaeogene orogenic wedge fed Fusaru fans with poorly sorted lithic sand. The Fusaru fans trend northwards in the foredeep basin having an elongate depocentre, interfingering and then overlapping on the distal part of the Kliwa depositional system due to the eastward advance of the Carpathian fold‐and‐thrust belt. A smaller sediment input is supplied by southern continental areas (i.e. Moesian Platform, North Dobrogea and potentially the Balkans). In general, the sandstone interfingering between distinct basin floor fan systems is less well documented because the facies would be similar and there are not many systems that have a distinct sediment provenance like Kliwa and Fusaru systems. This case study improves the understanding of regional palaeogeography and sedimentary routing systems and provides observations relevant here or elsewhere on the interfingering turbidite fan systems. [ABSTRACT FROM AUTHOR]

The Messinian Salinity Crisis is well known to have resulted from a significant drop of the Mediterranean sea level. Considering both onshore and offshore observations, the subsequent reflooding is generally thought to have been very sudden. We present here offshore seismic evidence from the Gulf of Lions and re-visited onshore data from Italy and Turkey that lead to a new concept of a two-step reflooding of the Mediterranean Basin after the Messinian Salinity Crisis. The refilling was first moderate and relatively slow accompanied by transgressive ravinement, and later on very rapid, preserving the subaerial Messinian Erosional Surface. The amplitude of these two successive rises of sea level has been estimated at ≤500 m for the first rise and 600-900 m for the second rise. Evaporites from the central Mediterranean basins appear to have been deposited principally at the beginning of the first step of reflooding. After the second step, which preceeded the Zanclean Global Stratotype Section and Point, successive connections with the Paratethyan Dacic Basin, then the Adriatic foredeep, and finally the Euxinian Basin occurred, as a consequence of the continued global rise in sea level. A complex morphology with sills and sub-basins led to diachronous events such as the so-called ' Lago Mare'.This study helps to distinguish events that were synchronous over the entire Mediterranean realm, such as the two-step reflooding, from those that were more local and diachronous. In addition, the shoreline that marks the transition between these two steps of reflooding in the Provence Basin provides a remarkable palaeogeographical marker for subsidence studies. [ABSTRACT FROM AUTHOR]

ABSTRACT The timing of deformation in the northern Zagros Folded Belt is poorly constrained because of the lack of an accurate absolute chronology of the syntectonic sedimentary sequences. The foreland basin infill in the northern part of the Fars arc is composed of supratidal sabkha deposits (Razak Fm), medium-grained deltaic deposits (Agha Jari Fm) and coarse conglomerates of nearshore fan delta deposits at the base (Bakhtyari Fm, Bk1) and continental alluvial deposits at the top of the section (Bakhtyari Fm, Bk2). A magnetostratigraphic study was carried out in a composite section spanning about 1300 m on the northern flank of the Chahar-Makan syncline. Magnetostratigraphic correlation of the Razak Fm with chron C6n yields an age of 19.7 Ma at the base of the composite section. The transition to Agha Jari Fm is correlated with chron C5Cn, yielding an age of 16.6 Ma. The transition to the conglomerates of the Bakhtyari Fm (Bk1) correlates with the chron C5AD at approximately 14.8 Ma, which is considerably older than previously thought. The base of the Bakhtyari Fm growth strata, and thus the beginning of the deformation in northern Fars, is dated at 14-15 Ma. The topmost preserved Bakhtyari Fm (Bk1) is folded and unconformably overlain by Bakhtyari Fm (Bk2) conglomerates. This indicates that tectonic deformation in northern Zagros was already underway in the Middle Miocene. [ABSTRACT FROM AUTHOR]