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A taxonomic study of the Paleocene larger foraminifera from the Pyrenean basin has led to the description of sixty taxa including two new species: Alveolina korresensis and Valvulineria bacetai. In this work, we present a chronostratigraphic recalibration of the Paleocene Shallow Benthic Zones SBZ 1 to SBZ 4 based on correlation with calcareous nannofossil and planktic foraminifera biozones, all integrated within the stratigraphic framework of Paleocene platform to basin depositional sequences established for the whole Pyrenean domain. The samples were collected in autochtonous and parautochtonous deposits from ten key stratigraphic sections, representative of coastal to platform margin depositional settings. The results from two sections representing base of slope facies with intercalations of calcareous turbidites, which include penecontemporaneous platform-derived biota have been integrated in the study. The regional chronostratigraphic framework is derived from magneto-biochronological studies carried out in the Zumaia section, the global reference section for the Danian-Selandian and Selandian-Thanetian GSSPs. A new calibration of the Paleocene SBZs is proposed. The SBZ 1 is constrained to the first 1.09m.y. of the Paleocene; this first Paleogene biozone lacks distinct larger foraminiferal markers and thus is defined by an association of non-exclusive taxa composed of Valvulineria patalaensis, Stomatorbina? binkhorsti, Planorbulina? antiqua and Bangiana hanseni. The SBZ 2 now appears as the biozone encompassing most of the Danian stage (from ca. 64.9m.a. to 61.6m.a.), and is characterized by the association of Haymanella elongata, Haymanella paleocenica, Kayseriella decastroi, Rotospirella conica, Pyrenerotalia depressa, Elazigin dienii, Ornatononion moorkensii and Paralockhartia eos. The SBZ 2-SBZ 3 boundary coincides with the base of the Selandian stage (ca. 61.6m.a.). The SBZ 3 biozone is defined by the occurrence of Glomalveolina primaeva, Periloculina slovenica, Vania anatolica, Coskinon rajkae, Fallotella alavensis, Cribrobulimina carniolica, Miscellanea yvettae, Miscellanea juliettae, Miscellanites primitivus, Miscellanites minutus, Ranikothalia soldadensis, “Operculina” heberti and Discocyclina seunesi. The SBZ 3-SBZ 4 boundary is now ascribed to ca. 57.2m.a. The SBZ 4 biozone appears characterized by Glomalveolina levis, Alveolina korresensis, Hottingerina lukasi, Daviesina garumnensis, Assilina yvettae, Assilina azilensis and Nummulites catari. The SBZ 4-SBZ 5 boundary is placed at the Paleocene-Eocene boundary event (ca. 56.0m.a.).

During the Paleocene/Eocene Thermal Maximum, ~55.6 Ma, the Earth experienced the warmest event of the last 66 Ma due to a massive release of CO2. This event lasted for ~100 thousands of years with the consequent ocean acidification (estimated pH = 7.8-7.6). In this paper, we analyze the effects of this global environmental shift on coralline algal assemblages in the Campo and Serraduy sections, in the south-central Pyrenees (Huesca, N Spain), where the PETM is recorded within coastal-to-shallow marine carbonate and siliciclastic deposits. In both sections, coralline algae occur mostly as fragments, although rhodoliths and crusts coating other organisms are also frequent. Rhodoliths occur either dispersed or locally forming dense concentrations (rhodolith beds). Distichoplax biserialis and geniculate forms (mostly Jania nummulitica) of the order Corallinales dominated the algal assemblages followed by Sporolithales and Hapalidiales. Other representatives of Corallinales, namely Spongites, Lithoporella as well as Neogoniolithon, Karpathia, and Hydrolithon, are less abundant. Species composition does not change throughout the Paleocene/Eocene boundary but the relative abundance of coralline algae as components of the carbonate sediments underwent a reduction. They were abundant during the late Thanetian but became rare during the early Ypresian. This abundance decrease is due to a drastic change in the local paleoenvironmental conditions immediately after the boundary. A hardground at the top of the Thanetian carbonates was followed by continental sedimentation. After that, marine sedimentation resumed in shallow, very restricted lagoon and peritidal settings, where muddy carbonates rich in benthic foraminifera, e.g., milioliids (with abundant Alveolina) and soritids, and eventually stromatolites were deposited. These initial restricted conditions were unfavorable for coralline algae. Adverse conditions continued to the end of the study sections although coralline algae reappeared and were locally frequent in some beds, where they occurred associated with corals. In Serraduy, the marine reflooding was also accompanied by significant terrigenous supply, precluding algal development. Therefore, the observed changes in coralline algal assemblages during the PETM in the Pyrenees were most likely related to local paleoenvironmental shifts rather than to global oceanic or atmospheric alterations.

A taxonomic study of the larger foraminifera found in Paleocene rocks from the Pyrenean basin has led to the description of sixty taxa including two new species: Alveolina korresensis and Valvulineria bacetai. In this work, we present a chronostratigraphic recalibration of the Paleocene Shallow Benthic Zones (SBZ 1 to SBZ 4) based on correlation with calcareous nannofossil and planktic foraminifera biozones, all integrated within the stratigraphic framework of Paleocene platform to basin depositional sequences established for the whole Pyrenean domain. The samples were collected in autochtonous and parautochtonous deposits from ten key shallow platform stratigraphic sections, representative from coastal to platform margin depositional settings. The results from two base of slope sections with numerous intercalations of calcareous turbidites with penecontemporaneous platform-derived biota have been integrated in the study. The regional chronostratigraphic framework is derived from magneto-biochronological studies carried out in the Zumaia section, global reference section for the Danian-Selandian and Selandian-Thanertian GSSPs. The new calibration of the Paleocene SBZs is summarized as follows. The SBZ 1 is constrained to the first 1.09 m.y. of the Paleocene; this first Paleogene biozone lacks distinct larger foraminifera biomarkers and thus is defined by an association of non-exclusive taxa composed of Valvulineria patalaensis, Stomatorbina? binkhorsti, P.? antiqua and Bangiana hanseni. The SBZ 2 now appears as the biozone encompassing most of the Danian stage (from ca. 64.91 m.y. to 61.6 m.y.), and is characterized by the association of Haymanella elongata, Haymanella paleocenica, Kayseriella decastroi, Rotospirella conica, Pyrenerotalia depressa, Elazigina dienii and Paralockhartia eos. The SBZ 2-SBZ 3 boundary coincides with the base of the Selandian stage (ca. 61.6 m.y.). The SBZ 3 biozone is defined by Glomalveolina primaeva, Periloculina slovenica, Vania anatolica, Coskinon rajkae, Fallotella alavensis, Cribrobulimina carniolica, Miscellanea yvettae, Miscellanea juliettae, Miscellanites primitivus, Miscellanites minutus, Ranikothalia soldadensis, Nummulites heberti and Discocyclina seunesi. The SBZ 3-SBZ 4 boundary is now ascribed to ca. 57.2 m.y. The SBZ 4 biozone appears characterized by Glomalveolina levis, Alveolina korresensis, Hottingerina lukasi, Daviesina garumnensis, Assilina yvettae, Assilina azilensis and Nummulites catari. The SBZ 4-SBZ 5 boundary is placed at the Paleocene-Eocene boundary event (ca. 56.0 m.y.).

The study across the Pliensbachian–Toarcian boundary sedimentary record in the Bizanet section of the Pyrenean Basin (southern France) revealed the presence of solid bitumen. This secondary organic matter was characterized using petrographic (transmitted and reflected white lights, incident blue light, and scanning electron microscopy) and geochemical (total organic carbon, total sulfur, and insoluble residue) techniques. The spore coloration index (SCI) was also determined. With the characterization of the optical properties and reflectance of the solid bitumen, it was possible to distinguish four different families (A–D) that display a wide range of reflectance values, from 0.21% to 2.64% BRr, i.e., from glance pitch to meso-impsonite. SCI values were higher than 9–9.5 (%Req > 1.50%). The comparison between the equivalent vitrinite reflectance values of the solid bitumen and SCI showed that this index and the solid bitumen D values are concordant, indicating that solid bitumen D can be considered an indigenous bitumen. The other three families of solid bitumen (A–C) are considered as having migrated. The laterally equivalent Pont de Suert section (South Pyrenean Zone) displays no trace of solid bitumen which points to the important role of the morphotectonic context of the Bizanet section in the migration of these hydrocarbons, namely, the presence of a major thrust fault in the eastern Corbières close to the section’s location.

A taxonomic study of the Paleocene larger foraminifera from the Pyrenean basin has led to the description of sixty taxa including two new species: Alveolina korresensis and Valvulineria bacetai. In this work, we present a chronostratigraphic recalibration of the Paleocene Shallow Benthic Zones SBZ 1 to SBZ 4 based on correlation with calcareous nannofossil and planktic foraminifera biozones, all integrated within the stratigraphic framework of Paleocene platform to basin depositional sequences established for the whole Pyrenean domain. The samples were collected in autochtonous and parautochtonous deposits from ten key stratigraphic sections, representative of coastal to platform margin depositional settings. The results from two sections representing base of slope facies with intercalations of calcareous turbidites, which include penecontemporaneous platform-derived biota have been integrated in the study. The regional chronostratigraphic framework is derived from magneto-biochronological studies carried out in the Zumaia section, the global reference section for the Danian-Selandian and Selandian-Thanetian GSSPs. A new calibration of the Paleocene SBZs is proposed. The SBZ 1 is constrained to the first 1.09m.y. of the Paleocene; this first Paleogene biozone lacks distinct larger foraminiferal markers and thus is defined by an association of non-exclusive taxa composed of Valvulineria patalaensis, Stomatorbina? binkhorsti, Planorbulina? antiqua and Bangiana hanseni. The SBZ 2 now appears as the biozone encompassing most of the Danian stage (from ca. 64.9m.a. to 61.6m.a.), and is characterized by the association of Haymanella elongata, Haymanella paleocenica, Kayseriella decastroi, Rotospirella conica, Pyrenerotalia depressa, Elazigina dienii, Ornatononion moorkensii and Paralockhartia eos. The SBZ 2-SBZ 3 boundary coincides with the base of the Selandian stage (ca. 61.6m.a.). The SBZ 3 biozone is defined by the occurrence of Glomalveolina primaeva, Periloculina slovenica, Vania anatolica, Coskinon rajkae, Fallotella alavensis, Cribrobulimina carniolica, Miscellanea yvettae, Miscellanea juliettae, Miscellanites primitivus, Miscellanites minutus, Ranikothalia soldadensis, "Operculina" heberti and Discocyclina seunesi. The SBZ 3-SBZ 4 boundary is now ascribed to ca. 57.2m.a. The SBZ 4 biozone appears characterized by Glomalveolina levis, Alveolina korresensis, Hottingerina lukasi, Daviesina garumnensis, Assilina yvettae, Assilina azilensis and Nummulites catari. The SBZ 4-SBZ 5 boundary is placed at the Paleocene-Eocene boundary event (ca. 56.0m.a.). [ABSTRACT FROM AUTHOR]

Abstract Ronchi et al. (in press) comment on the stratigraphic, sedimentological, mineralogical and palaeontological analyses performed in the recently described Coll de Terrers Permian–Triassic terrestrial succession from the Catalan Pyrenees by Mujal et al. (2017a). The comment debates our interpretation of a succession of red-beds as Permian (Upper Red Unit, URU). Instead, the comment infers that the analysed succession is part of the regional upper Buntsandstein facies unit (Triassic), debating the proposed stratigraphic scheme by using the tectonic evolution as the main argument. Here, we clarify and present more details on the interpretation published in Mujal et al. (2017a). Based on this clarification and taking into account the comment, we arrive to the conclusion that the interpretation and inferences presented in Mujal et al. (2017a) are sound and justified. Highlights • Reply to comment on Mujal et al. (2017a) study of the Permian–Triassic transition at Coll de Terrers (Catalan Pyrenees). • Previously exposed ideas derived from the originally published data are shown as valid. • The proposed stratigraphic framework is discussed and demonstrated as valid, further studies on the region are encouraged. [ABSTRACT FROM AUTHOR]

The Carboniferous–Permian terrestrial successions record a global climatic shift from icehouse to hothouse conditions. Our multidisciplinary study documents an aridification trend throughout the ~ 1000 m thick composite terrestrial succession of the western Catalan Pyrenees (NE Iberian Peninsula), representing this time period. The detailed stratigraphic framework integrates sedimentology, paleopedology, biochronology (plant fossils and tetrapod footprints) and geochronology (paleomagnetism). Additional absolute age correlation is also carried out. The new and reviewed data show that the late Carboniferous wet environments (with short drought periods) progressively changed to a strong seasonal semi-arid and arid climate (with short humid periods) through the early Permian. This paleoclimatic trend supports the previously suggested aridification of the Pangean pan-tropical belt, and supports the hypothesis of the influence of the recurrent climatic fluctuations in Central Pangea, being tentatively correlated to the Southern Gondwanan glaciation-deglaciation periods. Therefore, the Carboniferous–Permian terrestrial succession from the Catalan Pyrenees emerges as a continuous record that can help to constrain late Paleozoic paleoenvironmental events. [ABSTRACT FROM AUTHOR]

An integrated magneto-biostratigraphic study, based on calcareous nannofossils, was carried out on the Eocene uppermost marine deposits of the southeastern Pyrenean foreland basin. The study was performed along six sections of the upper portion of Igualada Formation, cropping out in the Vic area. Common late Middle/Upper Eocene nannofossil assemblages allow recognizing, within a normal magnetozone or immediately below, the FO of Istmolithus recurvus, which identifies the base of NP19 Zone, in the Priabonian. This event occurs within C16n.2n magnetozone in several oceanic and Mediterranean sections, which allows the correlation of the normal magnetozone in the Vic area to chron C16n.2n. This challenges previous magnetostratigraphic interpretations in the Vic area that correlated the uppermost marine sediments to chron C17n. The estimated age for the FO of I. recurvus is 36 Ma and collectively with the magnetostratigraphic data indicates that the uppermost marine sediments in the basin are of Priabonian age. The new results indicate that the entire chronology of the marine strata needs reassessment. The thickness of chron C16n.2n varies from 45 m in the Collsuspina area (southern sector) to about 270-290 m in the Sant Bartomeu del Grau area (northern sector), which is indicative of a marked asymmetry in the basin deposition.

Abstract: The current available Shallow Benthic Zones (SBZs) calibration based on larger foraminifera is now being improved for the Paleogene Period. In this work, the San Pelegrín section in the External Sierras, shows new magnetostratigraphic and biostratigraphic information from the Southwestern Pyrenean basin, where the larger thickness of the shallow marine platforms were developed. This environment represents the appropriate frame to calibrate the SBZ scale. Moreover the magnetostratigraphic data can be correlated with biostratigraphic data obtained directly at the same section, avoiding limitations of previous correlations. The San Pelegrín section presents 530m of Ypresian and Lutetian rocks; 169 sampled levels for magnetostratigraphic purposes have been studied, a fact that guarantees the independence and resolution of this record. Thermal and alternating field demagnetizations were carried out to unravel the characteristic remanent magnetization, and the orthogonal diagrams show stable normal and reverse polarity directions. Three pairs of magnetozones were found along the section enabling to define a robust and reliable local polarity sequence correlated with chrons C23, C22, C21n and C20r. The biostratigraphic study distinguished three Shallow Benthic Zones from SBZ11 to SBZ13. The combination of magneto and biochronologic scales is very useful to improve and to accurate the available shallow benthic zone calibration for this time gap, especially for the SBZ11 zone. Now the base of SBZ11 can be located, at least, in 50.96My, because the association is still present at the top of C23n. This data is older than previously thought from existent scales. On the other side, the SBZ11 top falls within chron C22n. The occurrence of a sedimentary hiatus between C22n and C21n prevents an accurate calibration of the SBZ12 top, but our profile proves the relation of SBZ12 with C22n as well. Finally the SBZ13 zone falls within the limits of recent recalibrations (C21n to C20r). [Copyright &y& Elsevier]

The study across the Pliensbachian–Toarcian boundary sedimentary record in the Bizanet section of the Pyrenean Basin (southern France) revealed the presence of solid bitumen. This secondary organic matter was characterized using petrographic (transmitted and reflected white lights, incident blue light, and scanning electron microscopy) and geochemical (total organic carbon, total sulfur, and insoluble residue) techniques. The spore coloration index (SCI) was also determined. With the characterization of the optical properties and reflectance of the solid bitumen, it was possible to distinguish four different families (A–D) that display a wide range of reflectance values, from 0.21% to 2.64% BRr, i.e., from glance pitch to meso-impsonite. SCI values were higher than 9–9.5 (%Req > 1.50%). The comparison between the equivalent vitrinite reflectance values of the solid bitumen and SCI showed that this index and the solid bitumen D values are concordant, indicating that solid bitumen D can be considered an indigenous bitumen. The other three families of solid bitumen (A–C) are considered as having migrated. The laterally equivalent Pont de Suert section (South Pyrenean Zone) displays no trace of solid bitumen which points to the important role of the morphotectonic context of the Bizanet section in the migration of these hydrocarbons, namely, the presence of a major thrust fault in the eastern Corbières close to the section's location. [ABSTRACT FROM AUTHOR]

Abstract: Calcareous red algae (corallines, ‘solenoporaceans’ and peyssonneliaceans) are major contributors to Paleocene platform deposits in the Pyrenean Basin (N Spain) and Prebetic Zone (Betic Cordillera, SE Spain). The earliest Danian–middle Thanetian time interval in the Pyrenean Basin is represented by four depositional sequences, the Ma-Da (earliest Danian), Da-1 (early Danian), Da-2 (late Danian), and Th-1 (Selandian–mid Thanetian) sequences, from bottom to top. This precise chronostratigraphic framework allows an accurate assessment of the recovery of these calcareous algal groups after the Cretaceous–Tertiary (K/T) mass extinction. Calcareous algae are recorded shortly after the K/T boundary (∼0.2–0.3 Ma after the K/T), although the richness of identifiable species remains low during the Danian: 9 species in the earliest Danian, 9 species in the early Danian, and 11 species in the late Danian. In addition, no change in taxonomic composition is observed in this interval since approximately the same algal species occur in all three Danian sequences. The same low species richness (11 species) and species composition is observed in the Danian algal assemblages of the Betic Cordillera. However, this low level of diversification changes radically in the Selandian–mid Thanetian interval, when 29 species are recorded. Together with the increase in species richness, the taxonomic composition also changes, since 19 species of corallines are recorded for the first time in the Th-1 sequence. Therefore, it can be deduced that species diversity recovery due to a significant radiation of corallines was delayed ∼6 Ma after the end-Cretaceous event. The recovery of corallines during the Paleocene shows a characteristic depth-dependent pattern. Throughout the Danian–middle Thanetian interval, representatives of the family Hapalidiaceae subfamily Melobesioideae and plants of the family Sporolithaceae largely dominate the algal assemblages in the deep-water, outer-platform settings, as they do in present-day seas. Members of these two groups are also the most abundant coralline algae in the Paleocene reef and back-reef paleoenvironments, indicating that the shallowest and best-illuminated areas were occupied by algal groups that in modern tropical seas mainly occur in relatively deep habitats. This suggests that all platform habitats were re-occupied after the end-Cretaceous event by the groups that selectively survived the extinction. Only after a time interval of about 6 Ma did the habitat distribution of coralline groups change to its modern patterns. The subfamilies most abundant in present-day shallow tropical waters, that is, Mastophoroideae and Lithophylloideae, for the first time account for more than 1% of the algal assemblages in the Thanetian and even then they remain very minor components. These shallow-water coralline groups were affected more intensively by the K/T extinction event, accounting for the delay in their recovery in their preferred shallow-water habitats. Shallow-water lithophylloids and geniculate corallines have not been found in Danian sequences. [Copyright &y& Elsevier]

This work focuses on the Olenekian-Anisian (Early-Middle Triassic) continental record of the Central-Eastern Pyrenean basin (NE Spain), a near-equator (10°-14°N) basin located in the western peri-Tethys margin, inside the Variscan fold-belt. Due to the mass mortality of the end-Permian and the subsequent Smithian-Spathian Boundary (SSB) crisis, the Early Triassic and its transition to the Middle Triassic was a time period with intermittent stages of environmental instability that affected fauna and flora intensely. Compared to other crisis, a remarkable feature is the longer time required to achive life recovery during this time-interval and the fact that continental environments have been less globally studied than their marine counterparts. Furthermore, in SW Europe there is almost no sedimentary continental record from the beginning of the Triassic. This multidisciplinary study, embracing sedimentology, mineralogy, palaeontology, palaeopedology and palaeogeography, of 10 complete and well dated Early-Middle Triassic field sections has allowed (1) the location and characterization of the oldest Mesozoic sedimentary record in the basin, which is of late Smithian age and overlies the late-middle Permian continental rocks and of (2) the Smithian-Spathian transition (SST), (3) the timing of life recovery during the late Spathian-Anisian, (4) the characterization of the first incursion of the Tethys sea into the basin, and (5) the comparison of the evolution of this basin with other basins of the same age in SW Europe. The SST coincides with hyper-arid climate conditions, evolving to semi-arid in the late Spathian and semi-arid to semi-humid in Anisian times. Poorly sorted breccias and conglomerate alluvial sheets with aeolian reworking dominate the SST, as a result of these environmental changes and tectonicsA broader comparison, based on stratigraphic studies by other authors, indicates less aridity in the basin studied compared to other SW Europe basins in the same period, maybe due to its greater proximity to the equator. Sedimentary characteristics changed during the late Spathian, when sandy braided fluvial systems developed and the first dispersed plants, pollen assemblages and paleosols appeared. Well-developed floodplains and associated paleosols and plants developed during the early Anisian, when more humid conditions prevailed. The occurrence of aluminium phosphate-sulphate (APS) minerals might be considered as evidence of environmental acidification during the Olenekian with an amelioration during the early Anisian, as described in neighboring basins, although in the Pyrenean basin this acidification was probably less intensive. The first incursion of the Tethys sea reached the Central-Eastern Pyrenean basin during the Anisian-Ladinian transition, about 3 My later than in neighbouring Southwestern Europe basins. General comparison with other Early-Middle Triassic continental records of Western Europe basins indicates contrasting trends of climate and sedimentary evolution, probably related to the still prevailing great paleorelief of the Variscan foldbelt, where part of the study basin could constitute an elevated area during some time-intervals, possibly related to the so-called Ebro High. • Continental sedimentsation in the Central-Eastern Pyrenean basin started during the Smithian and lasted until the Fassanian. • The first Triassic marine incursion of the Tethys in the Central-Eastern Pyrenees basin was Fassanian (Ladinian) in age. • Fossil content after the SSB is very scarce all the Spathian in the study basin and increases inthe early Anisian. • Arid conditions in the Olenekian were less accused in the study basin when compared to others of similar age of SW Europe. [ABSTRACT FROM AUTHOR]