Fossil associations from the middle and upper Eocene strata of the Pamplona Basin and surrounding areas (Navarre, western Pyrenees)

Fossil associations from the middle and upper Eocene (Bartonian and Priabonian) sedimentary succession of the Pamplona Basin are described. This succession was accumulated in the western part of the South Pyrenean peripheral foreland basin and extends from deep-marine turbiditic (Ezkaba Sandstone Formation) to deltaic (Pamplona Marl, Ardanatz Sandstone and Ilundain Marl formations) and marginal marine deposits (Gendulain Formation). The micropalaeontological content is high. It is dominated by foraminifera, and common ostracods and other microfossils are also present. The fossil ichnoasssemblages include at least 23 ichnogenera and 28 ichnospecies indicative of Nereites, Cruziana, and ?Scoyenia-Mermia ichnofacies. Body macrofossils of about 80 taxa corresponding to macroforaminifera, sponges, corals, bryozoans, brachiopods, annelids, molluscs, arthropods, echinoderms and vertebrates have been identified. Both the number of ichnotaxa and of species (e. g. bryozoans, molluscs and condrichthyans) may be considerably higher. Body fossil assemblages are comparable to those from the Eocene of the Nord Pyrenean area (Basque Coast), and also to those from the Eocene of the west-central and eastern part of South Pyrenean area (Aragon and Catalonia). At the European scale, the molluscs assemblages seem endemic from the Pyrenean area, although several Tethyan (Italy and Alps) and Northern elements (Paris Basin and Normandy) have been recorded. Palaeontological data of studied sedimentary units fit well with the shallowing process that throughout the middle and late Eocene occurs in the area, according to the sedimentological and stratigraphical data.Se describen las asociaciones fósiles del Eoceno medio y superior (Bartoniense y Priaboniense) de la sucesión sedimentaria de la Cuenca de Pamplona. Esta sucesión se acumuló en la parte oeste de la Cuenca de antepaís periférica surpirenaica y comprende desde turbiditas marinas profundas (Formación Areniscas de Ezkaba) hasta depósitos deltaicos (Formaciones Margas de Pamplona, Areniscas de Ardanatz y Margas de Ilundain) y marinos marginales (Formación Gendulain). El contenido micropaleontológico es alto y está dominado por los foraminíferos. Los fósiles de ostrácodos y otros organismos son también abundantes. Las asociaciones de icnofósiles incluyen al menos 23 icnogéneros y 28 ichnoespecies, indicativas de las icnofacies de Nereites, Cruziana, y ?Scoyenia-Mermia. Se han identificado fósiles corporales de unos 80 taxones, correspondientes a macroforaminíferos, esponjas, corales, briozoos, braquiópodos, anélidos, moluscos, artrópodos, equinodermos y vertebrados. El número de icnotaxones y de especies (p. e. briozoos, moluscos gasterópodos, bivalvos y peces condríctios) puede ser considerablemente mayor. Las asociaciones de fósiles corporales son comparables a las del Eoceno del Área norpirenaica (Costa vasca) y de las partes central y este del Área surpirenaica (Aragón y Cataluña). A escala europea, la asociación de moluscos parece endémica del Área pirenaica, aunque contiene elementos del Tetis (Italia y Alpes) y de las cuencas del norte (Cuenca de París y Normandía). El contenido paleontológico de las unidades sedimentarias analizadas es coherente con el proceso de somerización que tiene lugar a lo largo del Eoceno medio y tardío, de acuerdo con lo que indican los datos sedimentológicos y estratigráficos.Comments by Dr. Kai Ingemann Schnetler and an anonymous reviewer considerably improved the manuscript. Financial support to H.A., A.Ba., A.Be., I. D.-M., J.E. and X.P.-S. was provided by the Project CGL2013-47521-P (Ministerio de Economia y Competitividad, Servicio de Estado de Investigacion, Desarrollo e Innovacion, MINECO, Spain), the European Regional Development Fund/Fondo Europeo de Desarrollo Regional (ERDF/FEDER), and the research group IT-834-13 (Eusko Jaurlaritza/Gobierno Vasco, EJ/GV). Research work of I.D.-M. was supported by a postdoctoral grant provided by the Ministerio de Ciencia, Tecnologia e Innovacion Productiva, Consejo Nacional de Investigaciones Cientificas y Tecnicas, Argentina. Financial support to F.J.R.-T. was provided by the Project CGL2012-33281 (Secretaria de Estado de I+D+I, MINECO, Spain), and the research group RNM-178 (Junta de Andalucia). A.P. and S.O. were funded by project CGL 2011-23770 (MINECO) and the research group IT-215-07 (EJ/GV)

The early/middle Eocene transition at the Ésera valley (SouthCentral Pyrenees) : implications in Shallow Benthic Zones (SBZ)

Acknowledgement. AB fieldwork has been supported by the project PGC2018-093903-C1, additional support came from the projects DR3AM (CGL2014-54118-C2-2-R) MAGIBERII (CGL2017-90632-REDT) and UKRIA4D (PID2019-104693GB-I00/CTA) all of them from the Spanish Science National Plan. The study of calcareous nannofossils was supported by the Research Group of the Basque University System IT-1602-22. Pablo Calvín gave us a hand with the reversal test in Python. The accurate and constructive comments from Johannes Pignatti, Elisabet Beamud, the Journal Manager Laura Rincón, and the editors Carles Martín Closas, Eulàlia Gili and Miguel Garcés helped to improve the original manuscript.An integrated study including magnetostratigraphy, larger benthic foraminifera and calcareous nannofossil biostratigraphy is presented herein. This work was performed in shallow marine siliciclastics rich in larger foraminifera, around the Ypresian/Lutetian boundary in the Ésera valley (South-Central Pyrenees). Although the calcareous nannofossil content in the studied interval is low, not allowing a precise Y/L boundary to be recognised, the taxa found are enough to support the chronostratigraphic attribution. Data obtained in the Ésera valley section has improved the knowledge of larger benthic foraminifera (Nummulites and Assilina) distribution through chron C21. SBZ 11 to SBZ 12 transition took place at the lowermost C21r, as shown in previous works. SBZ 12 assemblages extend into C21n, where the SBZ 12 to SBZ 13 boundary occurs. These data, obtained in shallow marine siliciclastic facies, with in situ fauna, results in a shift of the SBZ 12/SBZ 13 boundary to the Lower Lutetian, younger than previously believed. Accordingly, the Ypresian/Lutetian boundary occurs in SBZ 12

The early/middle Eocene transition at the Ésera valley (SouthCentral Pyrenees) : implications in Shallow Benthic Zones (SBZ)

Acknowledgement. AB fieldwork has been supported by the project PGC2018-093903-C1, additional support came from the projects DR3AM (CGL2014-54118-C2-2-R) MAGIBERII (CGL2017-90632-REDT) and UKRIA4D (PID2019-104693GB-I00/CTA) all of them from the Spanish Science National Plan. The study of calcareous nannofossils was supported by the Research Group of the Basque University System IT-1602-22. Pablo Calvín gave us a hand with the reversal test in Python. The accurate and constructive comments from Johannes Pignatti, Elisabet Beamud, the Journal Manager Laura Rincón, and the editors Carles Martín Closas, Eulàlia Gili and Miguel Garcés helped to improve the original manuscript.An integrated study including magnetostratigraphy, larger benthic foraminifera and calcareous nannofossil biostratigraphy is presented herein. This work was performed in shallow marine siliciclastics rich in larger foraminifera, around the Ypresian/Lutetian boundary in the Ésera valley (South-Central Pyrenees). Although the calcareous nannofossil content in the studied interval is low, not allowing a precise Y/L boundary to be recognised, the taxa found are enough to support the chronostratigraphic attribution. Data obtained in the Ésera valley section has improved the knowledge of larger benthic foraminifera (Nummulites and Assilina) distribution through chron C21. SBZ 11 to SBZ 12 transition took place at the lowermost C21r, as shown in previous works. SBZ 12 assemblages extend into C21n, where the SBZ 12 to SBZ 13 boundary occurs. These data, obtained in shallow marine siliciclastic facies, with in situ fauna, results in a shift of the SBZ 12/SBZ 13 boundary to the Lower Lutetian, younger than previously believed. Accordingly, the Ypresian/Lutetian boundary occurs in SBZ 12

Los ostracódos de las arenas con "Heterostegina" de la formación "calcarenita de Niebla" (Depresión del Guadalquivir, S.O. de España)

El estudio de las asociaciones de ostrácodos de las arenas basales con microforaminíferos de la Formación "Calcarenita de Niebla" (Civis et al., 1987) indican una edad Tortoniense para estos materiales. Su depósito se produjo en un medio infralitoral muy somero, bien oxigenado y con una importante vegetación.The ostracod assemblages of the basal sands with Heterostegina of the "Calcarenita de Niebla" Formation (Civis et al, 1987) indicates a Tortonian age. These materials were deposited in an infralittoral environment, well oxigenated and vegetate

New Geological Evidence of the 1755 Lisbon Tsunami from the Rock of Gibraltar (Southern Iberian Peninsula)

This paper presents the easternmost mineralogical and geochemical evidence of the 1755 Lisbon tsunami found in the Western Mediterranean. This multidisciplinary analysis of a sediment core obtained in Gibraltar (southern Iberian Peninsula) has allowed us to differentiate a tsunamiite from an old lagoon (The Inundation). This tsunamigenic layer has increased levels of calcite and aragonite and higher concentrations of Ba and ferromagnesian elements in comparison with the underlying lagoonal sediments of this core. This layer is also differentiated by its paleontological record, with the introduction of marine species within this lagoon. The uppermost part of the core includes a transition from swampy/marsh paleoenvironments to terrestrial scenarios, with a final anthropogenic filling occurring during the last centuryThis work was carried out through the following projects: a) DGYCIT project CTM2006- 06722/MAR; b) DGYCIT project CGL2006-01412; and c) FEDER 2014-2020 project UHU-1260298. Other funds have come from Autonomous University of Madrid (GPG-418 Research Group) and the Andalusian Government (groups RNM-238, RNM-293 and RNM-349). It is a contribution to the Research Center in Historical, Cultural and Natural Heritage (CIPHCN) of the University of Huelv

New fossils of Sirenia from the Middle Eocene of Navarre (Western Pyrenees) : the oldest West European sea cow record

Postcranial remains of Sirenia from the early Middle Eocene (late Lutetian) Urbasa-Andia Formation of Navarre (Western Pyrenees) are described. The material consists of two partial atlas vertebrae, one humerus and several dorsal ribs (from Arrasate, Urbasa plateau), and partial dorsal ribs (from Lezaun, Andia plateau). The morphology of the fossils is consistent with referral to Dugongidae, the only sirenian clade known so far in the Middle Eocene of Europe. Moreover, the histological study of the ribs shows that the pachyosteosclerosis of extant Sirenia was definitively present by the early Middle Eocene. The oldest sirenian remains reported to date in the Pyrenean Realm were assigned to the Biarritzian, a regional stage that is currently ascribed either to the middle or to the lower-middle Bartonian. Therefore, the sirenian remains of Lezaun, reliably dated as late Lutetian (SBZ16 zone) in age, are definitively the earliest sirenian fossils known in Western Europe and are among the oldest sea cow records of Europe

Redefinition of the Ilerdian Stage (early Eocene)

The Ilerdian Stage was created by Hottinger and Schaub in 1960 to accommodate a significant phase in the evolution of larger foraminifera not recorded in the northern European basins, and has since been adopted by most researchers working on shallow marine early Paleogene deposits of the Tethys domain. One of the defining criteria of the stage is a major turnover of larger foraminifera, marked by the FO's of Alveolina vredenburgi (formerly A. cucumiformis) and Nummulites fraasi. There is now conclusive evidence that this turnover was coeval with the onset of the Carbon Isotope Excursion (CIE) and, consequently, with the Paleocene-Eocene (P-E) boundary, a temporal correspondence that reinforces the usefulness of the Ilerdian as a chronostratigraphic subdivision of the early Eocene in a regional context. However, in addition to the paleontological criteria, the definition of the Ilerdian was also based on the designation of two reference sections in the southern Pyrenees: Tremp (stratotype) and Campo (parastratotype). In both sections, the base of the stage was placed at the lowest marine bed containing A. vredenburgi specimens. Using the CIE as a correlation tool we demonstrate that these two marine beds occur at different chronological levels, being older in Campo than in Tremp. Further, we show that both beds are in turn younger than the lowest strata with Ilerdian larger foraminifera at the deep-water Ermua section in the Basque Basin (western Pyrenees). Since the age of stage boundaries must be the same everywhere, the choice of these stratotype sections was misleading, since in practice it resulted in the Ilerdian being used as a facies term rather than as a chronostratigraphic unit. To eliminate that conflict, and yet be respectful with established tradition, we propose to redefine the Ilerdian Stage following a procedure similar to the one used by the International Commission on Stratigraphy to establish global chronostratigraphic standards, namely: by using a "silver spike" to be placed in the Tremp section at the base of the Claret Conglomerate, a widespread lithological unit that in the Tremp Graus Basin coincides with the onset of the CIE. The redefined regional Ilerdian Stage becomes thus directly correlatable to the lower part of the global Ypresian Stage, as currently defined by the International Commission on Stratigraphy

An inventory of the marine and transitional Middle/Upper Eocene deposits of the Southeastern Pyrenean Foreland Basin (NE Spain)

In the southeastern Ebro Foreland Basin, the marine deposits of Lutetian and Bartonian age show excellent outcrop conditions, with a great lateral and horizontal continuity of lithostratigraphic units. In addition, the rich fossil record -mainly larger foraminifers-, provides iostratigraphic data of regional relevance for the whole Paleogene Pyrenean Basin, that can be used for the Middle Eocene biocorrelation of the western Tethys. This contribution is a sedimentary and biostratigraphic synthesis of the basic outcrops and sections of the Lutetian and Bartonian marine and transitional deposits in the southeastern sector of the Ebro Foreland Basin

An inventory of the Marine and Transitional Middle/Upper Eocene Deposits of the Southeastern Pyrenean Foreland Basin (NE spain)

In the southeastern Ebro Foreland Basin, the marine deposits of Lutetian and Bartonian age show excellent outcrop conditions, with a great lateral and horizontal continuity of lithostratigraphic units. In addition, the rich fossil record -mainly larger foraminifers-, provides iostratigraphic data of regional relevance for the whole Paleogene Pyrenean Basin, that can be used for the Middle Eocene biocorrelation of the western Tethys. This contribution is a sedimentary and biostratigraphic synthesis of the basic outcrops and sections of the Lutetian and Bartonian marine and transitional deposits in the southeastern sector of the Ebro Foreland Basin