Although the Neuquén basin in Argentina forms a key transitional domain between the south‐central Andes and the Patagonian Andes, its Cenozoic history is poorly documented. We focus on the sedimentologic and tectonic evolution of the southern part of this basin, at 39–40°30′S, based on study of 14 sedimentary sections. We provide evidence that this basin underwent alternating erosion and deposition of reworked volcaniclastic material in continental and fluvial settings during the Neogene. In particular, basement uplift of the Sañico Massif, due to Late Miocene–Pliocene intensification of tectonic activity, led to sediment partitioning in the basin. During this interval, sedimentation was restricted to the internal domain and the Collon Cura basin evolved towards an endorheic intermontane basin. From stratigraphic interpretation, this basin remained isolated 7–11 Myr. Nevertheless, ephemeral gateways seem to have existed, because we observe a thin succession downstream of the Sañico Massif contemporaneous with the Collon Cura basin‐fill sequence. Comparisons of stratigraphic, paleoenvironmental and tectonic features of the southern Neuquén basin with other foreland basins of South America allow us to classify it as a broken foreland with the development of an intermontane basin from Late Miocene to Late Pliocene. This implies a thick‐skinned structural style for this basin, with reactivation of basement faults responsible for exhumation of the Sañico Massif. Comparison of several broken forelands of South America allows us to propose two categories of intermontane basins according to their structural setting: subsiding or uplifted basins, which has strong implications on their excavation histories.

-The Tithonian-Berriasian interval in the southern part of the Neuquén Basin is represented by the Vaca Muerta and the Pic un Leuf u Formations. Facies analysis and correlation of the Vaca Muerta Formation and the lower part of the Pic un Leuf u Formation in the Pic un Leuf u Anticline allow us to characterize the evolution of successive facies belts representing siliciclastic shelf and mixed ramp environments. Shoreface and offshore facies are developed on the siliciclastic shelf in the western and southern parts of the Pic un Leuf u Anticline. The offshore transition domain is characterized by storm beds and slump features, whereas the offshore domain corresponds to black to grey shales and turbidites. The mixed siliciclastic-carbonate ramp is characterized by the development of a lagoon and high-energy shoal in the proximal part of the inner ramp, whereas the distal part comprises a tidal complex. The mid-ramp zone is characterized by storm influence and the outer ramp by fine-grained deposits. Two major transgressiveregressive sequences and five high-frequency transgressive-regressive sequences are recognized. The highfrequency transgressive-regressive sequences make up three progradational sequences, an aggradationalprogradational sequence and an aggradational sequence. The geochemical characteristics and clay mineralogy of the Tithonian-Berriasian interval in the southern Neuquén Basin indicate that (1) climate played a key role in the evolution of the sedimentary environment, (2) a "normal marine" depositional environment with oxic sea water and sediment pore waters, rapidly changing to suboxic conditions at shallow depth below the seabed and (3) the occurrence of episodically restricted water-mass circulation at the onset of deposition of the Vaca Muerta Formation.Keywords: Vaca Muerta Formation / source rocks / siliciclastic shelf / mixed siliciclastic-carbonate ramp / sequence stratigraphy / oxygenation status Résumé -Évolution paléoenvironnementale de la partie sud du bassin de Neuquèn (Argentine) pendant l'intervalle tithonien-berriasien (formations Vaca Muerta et Pic un Leuf u) : approche multiproxy. L'intervalle tithonien-berriasien de la partie méridionale du bassin Neuquén est représenté par les formations de la Vaca Muerta et de Pic un Leuf u. L'analyse de faciès et la corrélation de logs sédimentaires de la formation de la Vaca Muerta et de la partie inférieure de la formation de Pic un Leuf u dans l'anticlinal Pic un Leuf u a permis de mettre en évidence un environnement de rampe silicoclastique évoluant vers un environnement de rampe mixte. En environnement de rampe silicoclastique, les faciès de shoreface et d'offshore se localisent dans les parties ouest et sud de l'anticlinal Pic un Leuf u. La zone de transition est caractérisée par des niveaux de tempête et des niveaux déstructurés et slumpés, alors que le domaine d'offshore correspond à des marnes noires à grises ainsi qu'à des niveaux de turbidites. La rampe mixte silicoclastique-carbonatée se caractérise dans sa partie proxima...

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Reconstruction of eroded mountain belt structures is crucial to produce valid precontractional palinspastic restorations and quantify the amount of shortening. In this study, we combine Raman Spectroscopy of Carbonaceous Material (RSCM) thermometry and cross-section balancing technique to propose a reconstruction of the thermal and deformational evolution of the Subalpine Digne Nappe in the southwestern French Alps. We sampled Mesozoic to Cenozoic sedimentary strata for RSCM thermometry analyses along the ~4-km-thick Digne Nappe to calculate maximum temperatures (T RSCM ). T RSCM values range from 243±10°C to 349±13°C in the upper Triassic-upper Cretaceous strata and from 255±19°C to 328±8°C in the overlying upper Eocene-lower Oligocene strata. T RSCM values show a gradual increase with depth and towards the inner part of the orogen. These results are consistent with a ~28±4°C/km modeled thermal gradient in the ~4-km-thick Digne Nappe 2 and suggest post Oligocene burial of the Digne Nappe under sedimentary/tectonic units that have been removed by erosion. Palinspastic restoration of a NE-trending and 65-km-long cross-section (Digne-Barcelonnette transect) constrained by thermal data supports the interpretation that the Digne Nappe involved a ~3-km-thick middle/upper Eocene-Oligocene to lower Miocene foreland basin tectonically overlain by the 3-to 11-km-thick Embrunais-Ubaye flysch nappes. The front of the Embrunais-Ubaye nappes was located ~40 km beyond its present erosional front. The amount of southwestward shortening in the Subalpine thrust wedge derived from palinspastic restoration is about 35 km (35%) over the past ~16 million years. Removal of a substantial volume of the southwestern Alpine orogen may have significantly influenced the dynamics of the Subalpine thrust wedge and Valensole foreland basin since the Middle Miocene.