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Despite increasing knowledge on the orogenic phases of the Pyrenees, the Neogene evolution of the range remains poorly constrained. The central Pyrenees, particularly the Ariège River valley and its terrace systems and glacial extensions, are key to reconstructing Pyrenean evolution during the Neogene. However, few terrace relics remain on the piedmont edges. To overcome this limitation and temporally extend the dataset obtained from terraces, we focus on alluvium-filled horizontal epiphreatic passages developed in limestone karstic networks. These landforms record the transient position of former local base levels during the process of valley deepening, similar to fluvial terraces. The alluvium fills of the studied caves in the Tarascon-sur-Ariège area, in the transition zone between the upper range and the piedmont, therefore enable the reconstruction of the geodynamic evolution of the Ariège River valley. All studied caves are developed on at least eight levels. Based on burial durations determined by 26 Al/ 10 Be and 10 Be/ 21 Ne terrestrial cosmogenic nuclide dating of samples from epiphreatic levels, our results indicate Langhian to Messinian (~13-5 Ma) incision rates averaging 48 m Myr-1. However, the obtained record does not allow us to accurately retrace the Pliocene evolution of the area due to the lack of known caves at corresponding levels. Moreover, raised local base levels during glacial phases both make the record more complex and call into question the methodological approach in terms of potential internal sediment remobilization and mixing related to implied re-flooding periods.

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. The oil field of Rospo Mare is located in the Adriatic Sea, 20 km of the Italian coast. The reservoir lies at a depth j of 1300 m and consists of a paleokarst of Oligocene to Miocene age which developed within cretaceous limestones, now covered by 1200 m of mio-pliocene sequences. The oil column is about 140 m high. The karstic nature of the reservoir was identified through vertical, cored drill holes which allowed the analysis of the various solution features and the sedimentary infilling (spe-leothems, terra rossa, marine clays), as well as their vertical distribution. Erosion morphology at the top of the karst is highly irregular, including more especially paleoval-leys as well as many pit-shaped sinkholes. Observations concerning the upper part of the reservoir were compared to a paléokarst of the same age, outcropping widely, onshore, in quarries located nearby. Detailed knowledge of that morphology through geophysics helped to optimize the development of the field through horizontal drilling. The paléokarst of Rospo Mare is an integral part of the ante miocene paléokarst assemblages of the periphery of the Mediterranean which were formed in tropical conditions.