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The Pyrenees display numerous paleomagnetic studies acquired during the past six decades after the pioneer works carried out by the University of Utrecht in the early sixties (Van der Voo, 1969 and references therein). Currently, the Pyrenean Paleomagnetic Database (of IGME) includes nearly 40,000 individual vectors (demagnetizations) from more than 3000 sampling sites and more than 170 magnetostratigraphic profiles (comprising more than 35 kilometres of sections) that are harmonized and synthesized. This implies a significant increase (ca. 20%) with respect to previous versions introduced in the Iberian paleomagnetic meeting in 2017. This outstanding amount of data (considering the rather small size of the Pyrenees) is due to: 1) excellent outcrop conditions of stratigraphic sequences and biostratigraphic calibrations with global interest; 2) the availability of synorogenic materials, allowing for an accurate dating of deformation processes; and 3) the occurrence of well-exposed areas affected by lateral transference of deformation (oblique structures) that have motivated abundant paleomagnetic studies focused on characterizing vertical-axis rotations.In this work we present the state of the art of the Pyrenean Paleomagnetic Database. About 75% of the compiled paleomagnetic data display fisherian means with alfa95 below 15° (84% below 20°) that are in agreement to standard reliability criteria of paleomagnetic data in tectonic studies. Most sites and localities are drilled in Cenozoic (Miocene to Paleocene) and Upper Cretaceous rocks, thus, coeval or younger than the Pyrenean convergence time. Sites in Lower Cretaceous and Jurassic rocks represent pre-orogenic stages and are coeval or older than the rotation of Iberia (Biscay Bay opening). Less than 15% of the paleomagnetic sites come from Triassic and Permian red-beds and display an uneven distribution along the mountain chain. A similar uneven distribution of sites is observed in Paleozoic rocks. Several studies have determined remagnetization processes in the Pyrenees from the Western Basque Palaeozoic massifs to other Palaeozoic rocks of the Axial Zone mostly in relation to burial processes. This is the case of Lower Cretaceous, highly subsiding basins, like Organyá, Mauléon, Cotiella or the Chaînons Béarnais, as well as other Ceno-Mesozoic sequences in the Internal Sierras and related units; Larra-Monte Perdido, Nogueras, Boixols, Cadí, etc. In most cases, the remagnetization ages are Cenozoic when maximum temperatures were acquired at the base of the sequences during the convergence period or, in any case, younger than the rotation of Iberia and the opening of the Biscay Bay. Van der Voo, R. (1969). Paleomagnetic evidence for the rotation of the Iberian Peninsula. Tectonophysics, 7(1), 5-56.

An extense systematic description of the Eocene larger foraminiferal faunas recorded in the South Pyrenean Basin (Sierras Exteriores) is presented herein. The large dataset provided in this work includes both Nummulites and Alveolina species, along with a variety of other porcellaneous and hyaline taxa with lesser biostratigraphic relevance, are represented. The larger foraminifera described in this work correspond mainly to the Lutetian (SBZ13 to SBZ16 biozones) interval, but late Ypresian (SBZ11, Cuisian) and Bartonian (SBZ17) shallow benthic zones have also been identified.As one of the most relevant results of this systematic analysis, a new species, Idalina osquetaensis, is described. The systematic revision of middle to late Lutetian alveolines led to a reassessment of A. fusiformis and the finding of two new precursor forms, described as affinis of their corresponding species, A. aff. fragilis and A. aff. elongata. The new forms A. aff. elongata and A. aff. fragilis fill the gap in the middle to late Lutetian alveolinid biostratigraphy. Despite not being exclusive to SBZ16, these new forms provide realiable biostratigraphic information where Nummulites are not present. This realibility lies on the correlation of Nummulites and Alveolina biomarkers in the same sections and their calibration to the global time scale through magnetostratigraphy. In fact, magnetostratigraphic calibration of all described taxa is also provided, along with an update of the SBZ calibration to the current Geologic Time Scale (Gradstein et al., 2012).

The Eocene record of turtle eggshells is scarce, with a single unconfirmed report from France. This scarcity contrasts with the great abundance of osteological remains, distributed over a wide palaeogeographical range as a result of climatic warmth. In this paper, we describe the first definitive Eocene Testudoolithidae eggshell fragments attributable to Testudines, most likely pleurodiran turtles, from the Eocene Sobrarbe Formation at the Castejon de Sobrarbe fossil site (CS-41) in northern Spain. The eggshells were found in association with osteological remains of at least four individuals of Eocenochelus eremberti (Pleurodira, Erymnochelyini) in an otherwise sirenian-dominated bonebed. Analysis of eggshell ultra- and microstructure allows comparison with eggshells from fossil and extant turtles. The eggshells are highly recrystallized but preserve relics of their original aragonitic radial ultrastructure as crystal phantoms. The barrel-shaped shell units, which are taller than wide, with compactituberculate ornamentation and funnel-shaped pore openings are similar to those of the Palaeocene ootaxon Haininchelys curiosa, whose holotype and paratype have been lost. The CS-41 eggshells are most similar to those of the pleurodiran Erymnochelys madagascariensis from Madagascar, the closest living relative to Eocenochelus, further supporting our attribution. Sedimentological and taphonomic analysis of the assemblage supports the hypothesis that the CS-41 fossil site was formed as the infilling of an abandoned tributary channel in the deltaic plain by an overbank or debris-flow deposit associated with a storm event. This storm resulted in the exhumation and subsequent re-sedimetation of the remains of a nesting ground of Eocenochelus eremberti, an otherwise coastal turtle, which would have entered inland streams to nest in the sand bars at the mouth of the Sobrarbe Deltaic Complex.

A detailed sedimentological and magnetostratigraphic analysis of three selected sections of the Eocene carbonate platforms of the South Pyrenean Jaca-Pamplona foreland basin has been carried out in the Aragonese External Sierras (Huesca, Spain). The stratigraphic record spans from the middle-late Lutetian (Chron 20r, SBZ15) to the Bartonian (Chron 18r, SBZ17). The Lutetian-Bartonian transition was characterized by a major paleogeographic change, from a turbiditic foredeep with associated peripheral carbonate ramps to deltaic sedimentation. In most of the outcrops of the External Sierras, the peripheral carbonate platforms (Guara Formation) are overlained by prodelta and outer ramp marls (Arguis Formation). The drowning unconformity between these two formations in the outcrops located in the westernmost tip of the External Sierras is documented herein for the first time. In this area, the Guara Formation is overlain by glauconitic limestones deposited in a carbonate ramp setting. Between these units a characteristic unconformity is observed, with hard-ground formation and local evidence of subaerial exposure in the shallowest domains of the study area. The abundant glauconite found on top of this unconformity records a starvation period in the basin, followed by the development of a new carbonate ramp system during Bartonian times (Santo Domingo Member of the Arguis Formation). Magnetostratigraphic and sedimentological data show that tectonic tilting occurred in latest Lutetian times, prior to the drowning process. This suggests the influence of the flexural subsidence in the cratonic margin of the foreland as a result of the advance of a basement thrust in the hinterland. Nevertheless, the correlation of the uppermost Lutetian drowning unconformity with a basinwide regional sea level rise, which may have further been global, suggests an interplay between tectonic and eustatic processes in the drowning of the late Lutetian South Pyrenean carbonate ramps. In this work we point out a narrowing of the carbonate ramp, together with a relative sea level rise, as the processes responsible for the drowning of the Upper Guara Mb carbonate ramp. These processes could be responsible for the development of drowning unconformities in cratonic margins of other foreland basins. As carbonate ramps have a high sediment production potential, the narrowing of the carbonate factory could provide the conditions for the drowning of the carbonate ramp system in a subsequent sea level rise.