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The data were collected in the framework of the AleutBio project of BMBF grant 03G0293A to Prof. Dr. Angelika Brandt, Senckenberg Research Institute and Natural History Museum Frankfurt, Germany. The research of O. Miguez-Salas was funded by a Humboldt Postdoctoral Fellowship from the Humboldt Foundation and a Margarita Salas Fellowship from the Ministry of Spain and EU Next Generations projects. The research of F.J. Rodríguez-Tovar was supported by grant PID2019- 104625RB-100 funded by MCIN/AEI/ https://doi.org/10.13039/501100011033., The online version contains supplementary material available at https://doi.org/10.1038/s41598-023-34050-w, Paleodictyon is one of the most iconic and widespread of trace fossils in the geological record. However, modern examples are less well known and restricted to deep-sea settings at relatively low latitudes. Here, we report the distribution of Paleodictyon at six abyssal sites near the Aleutian Trench. This study reveals for the first time the presence of Paleodictyon at Subarctic latitudes (51°–53°N) and at depths over 4500 m, although the traces were not observed at stations deeper than 5000 m suggesting that there is some bathymetric constraint for the trace maker. Two small Paleodictyon morphotypes were recognized (average mesh size of 1.81 cm), one having a central hexagonal pattern, the other being characterized by a non-hexagonal pattern. Within the study area, Paleodictyon shows no apparent correlation with local environmental parameters. Finally, based on a worldwide morphological comparison, we conclude that the new Paleodictyon specimens represent distinct ichnospecies that are associated with the relatively eutrophic conditions in this region. Their smaller size may reflect this more eutrophic setting in which sufficient food can be obtained from a smaller area in order to satisfy the energetic requirements of the tracemakers. If so, then Paleodictyon size may provide some assistance when interpreting paleoenvironmental conditions., EU Next Generations PID2019-104625RB-100, Ministry of Spain, Wolfgang Borchert, Alexander von Humboldt-Stiftung AvH, Bundesministerium für Bildung und Forschung 03G0293A BMBF, Ministerio de Ciencia e Innovación MICINN, Agencia Estatal de Investigación AEI

Bioturbation can influence petrophysical properties (e.g., porosity, permeability) of sedimentary rocks and, in consequence, reservoir quality. The impact can be positive, negative, or neutral, requiring detailed ichnological analysis. Ophiomorpha, a branched cylindrical burrow with diagnostic peloidal wall, may be present in bioturbated reservoirs that exhibit properties of both superpermeability and reduced porosity/permeability. However, no mechanistic understanding of how Ophiomorpha positively or negatively impacts petrophysical properties has yet been established. This study presents highresolution X-ray microtomographic analysis of how the features of Ophiomorpha (i.e., peloidal wall vs. burrow fill) influence porosity distribution in deep-water deposits (Neogene Tabernas Basin, SE Spain). The results show that the peloidal burrow wall exhibits the lowest porosity (up to six orders of magnitude lower than burrow fill or host sediment), while surrounding sediment shows variable values. Abrupt porosity changes within the fill material likely relate to burrow-associated diagenesis. A refined understanding of the features of Ophiomorpha and their associated porosity distribution help to constrain understanding of their diverse impacts on reservoir properties., MCIN/AEI PID 2019-104625RB100, FEDER/Junta de Andalucia-Consejeria de Economia y Conocimiento/Projects P18RT-4074 B-RNM-072-UGR18 A-RNM-368-UGR20 PPJIA2021-07, Junta de Andalucia RNM-178, Universidad de Granada UCE-2016-05 University of Granada, Humboldt Postdoctoral Fellowship, Ministry of Science and Innovation, Spain (MICINN) IJC 2019038866-I

Traditionally, studies on turbiditic systems were mostly focused on sedimentological features, but later some other features as bioturbation have been included. Ichnological analysis is probed as a powerful tool for deep-sea sediments studies, revealing accurate information about palaeoenvironmental conditions during deposition. For the first time, a detailed ichnological and sedimentological integrative analysis focused on Miocene muddy turbiditic deposits from the westernmost Mediterranean at the Tabernas Basin (SE Spain) is here presented. The representative Rambla de Tabernas section has been selected to identify dominant palaeoenvironmental conditions before the deposition of the well-known Gordo megabed. The ichnological content reveals a trace fossil association comprising 26 ichnospecies, belonging to 14 ichnogenera ascribed to the Nereites ichnofacies in an overall stable and well oxygenated environment dominated by low-energy conditions. The distribution, and abundance of trace fossils, integrated with sedimentological information, allow to characterize variation in depositional conditions within the turbiditic system. Before deposition of the Gordo megabed, the turbiditic system in the lower part of the studied area had generalized low energy conditions. These conditions are probably linked to distal depositional areas, characterized by the record of the Paleodictyon ichnosubfacies in interbedded sandstones-mudstones, with a common occurrence of Tab/Tabc Bouma intervals. In contrast, higher energy conditions and deposition prevailed in proximal settings (e.g., channels and proximal lobes) in the upper part. They arecharacterized by the Ophiomorpha rudis ichnosubfacies in interbedded sandstones-mudstones with dominant Tab Bouma intervals. Additionally, the low ichnodiversity in comparison with similar deposits from other worldwide areas, is probably caused by the influence of local environmental conditions in the studied basin., This contribution was funded by research projects PID2019-104625RB-100 funded by MCIN/AEI/ 10. 13039/501100011033; by FEDER/Junta de Andalucía-Consejería de Economía y Conocimiento. Projects P18-RT-4074, B-RNM-072-UGR18 and A-RNM-368-UGR20 (FEDER Andalucía); by the Research Group RNM-178 (Junta de Andalucía) and by the Scientific Excellence Unit UCE-2016-05 (UGR). The research by JD was funded through the Juan de la Cierva Program (IJC2019-038866-I) and the Ramón y Cajal fellowship (RYC2021- 032385-I) by the Spanish Ministry of Science and Innovation. Funding for open access charge: Universidad de Granada / CBUA.

34th International Association of Sedimentologists (IAS) Meeting of Sedimentology, Sedimentology to face societal challenges on risk, resources and record of the past, 10-13 September 2019, Rome.-- 1 page, The occurrence of extensive Plio-Quaternary contourite drifts in the Alboran region has recently been well documented, principally using geophysical methods. However, the sedimentological characteristics are not yet well documented, in spite of the fact that they provide a record of palaeoceanographic/climate changes. In this study, the sedimentary and geochemical characteristics of the contourite drifts formed by the Western Mediterranean Deep Water (WMDW) are examined in a core transect represented by three cores at 631 m, 712 m, and 914 m water depth. Three facies (1 to 3) are defined based on a combination of sedimentological and Zr/Al ratio. Facies 1 is the most dominant and consists of silty-clay, representing the finest-grained sediments; Facies 2 is composed of bioturbated clayey-silt with a remarkable Zr/Al peak, deposited during the Younger Dryas; Facies 3 consists of the coarsest sediments (sand), deposited during Heinrich event 2. The latter two facies present a remarkable Zr/Al peak. The mainly fine-grained contourites allow the Alboran contourite drifts to be classified as ¿muddy contourites¿. The vertical succession of these three facies permits the definition of two bi-gradational sequence types. Sequence A, represented by the vertical succession of facies 1, 2, 3, 2, 1, corresponds to the standard contourite sequence model, while Sequence B is composed of a vertical succession of facies 1, 2, 1, and corresponds to partial contourite sequences. Both sequences, A and B, are linked to shifts in the strength of the bottom currents, from weak to strong and then back to weak, corresponding to acceleration/deceleration periods. To decode the contourite facies successions in terms of bottom current speed, a comparison between two binary plots has been made: magnitude changes in mean sortable silt (meanss in µm) and changes in WMDW flow speed (in cm/s) versus four periods of acceleration of bottom currents (a: 23.4- 19 ka, b: 17.8-16.2 ka; c:15.0-12.5 ka; d: 9.8-8.0 ka). The regional Alboran palaeo-WMDW flow speed has been assessed using a similar record (meanss) from another contourite drift in the NW Mediterranean at 2391 m wd, close to the formation zone of the water mass. This comparison reveals that the Alboran contourite drifts were affected by low (~1.5-5.5 cm/s) and moderate flow speeds (~8-13 cm/s). These palaeo-speeds are in the same range as modern oceanographic data, indicating that the WMDW flow operated on the construction of those drifts in two hydrodynamic scenarios: Scenario 1 corresponded to low bottom current speeds (< 5.5 cm/s) for the period b; Scenario 2 was defined by higher bottom current speeds (up to ~12.8 cm/s), during the periods a, c, and d. This research represents a prime example of bottom current effect on the construction of contourite drifts and how to apply fine-grained, mainly muddy contourites in sedimentological and palaeoceanographic studies, despite the strong bioturbation. The core transect provides a regional perspective of bottom current flow, from close to its formation area along its pathway, which is governed by topographic restrictions (e.g., seamounts and submarine canyons), Contribution from Project FAUCES CTM2015-65461-C2-R (MINECO/FEDER)

XV Reunión Nacional Cuaternario, 1-5 July 2019, Bilbao.-- 4 pages, 4 figures, Se presenta un estudio sedimentológico y cronoestratigráfico de las contornitas del Mar de Alborán (Mediterráneo SO) en base al registro sedimentario de dos testigos de sedimento. En este estudio se incorporan marcadores físicos de corrientes de fondo (¿sortable silt mean grain size¿ meanss) y marcadores químicos de cambios ambientales (Si/Si+Al y Zr/Al ratios) con el objeto de decodificar las sucesiones de contorníticas en términos de variabilidad de velocidad de las corrientes de fondo en relación con cambios paleoambientales. Estos resultados son validados con la inclusión del registro del meanss de un testigo localizado en el Mediterráneo Nor-Occidental. Este transecto proporciona una perspectiva regional de los cambios de velocidades de la corriente profunda del Mediterráneo Occidental durante los últimos 24 ka B.P., This work was supported by the FAUCES Project (CTM2015-65461-C2-R; MINECO /FEDER)

Abtsract presented in Spanish during the 35th Spanish Palaeontological Meeting in Baza, Spain

Conference paper presented in Prague during the 15th International Ichnofabric Workshop. This contribution shows a preliminary study of ichnological content of some contourite deposits from the NW Iberian Margin. Preliminary results reveal that conditions are changing during the deposition of bottom-current sediments and demostrates the useful of ichnofabric approach as a tool for contourite research.

The Laja Alta rock shelter paintings (Jimena de la Frontera, Spain) are the clearest existing testimony of sailing vessels from ancient times in the western Mediterranean. The majority opinion of the research has dated the naval scene in the first or the end of the second mill. BC. This article offers new reproductions and data for a better understanding of the figures represented. Based on the results obtained, we propose a different hypothesis. The absolute dates confirm that the rock shelter was used in the IV-III mill. cal. BC., the Late Neolithic and Copper Age. It was a time of important community transformations. Besides, others datas (types of figures, cultural context, pigment analysis by optical reflectance and superposition of figures) do not deviate from the results dates. The topographical distribution indicates that the boats occupy a central position in the rock shelter. Thus, the boats are the main theme of the paintings of Laja Alta and the rest of the motifs are determined by the naval scene. This conclusion has important historical implications for the transfer of technologies, goods and ideas that shaped the societies of the Late Neolithic and Copper Age of the Western Europe and North Africa. Las representaciones esquemáticas del abrigo de Laja Alta (Jimena de la Frontera, España) son el testimonio más claro de la existencia en la antigüedad de embarcaciones a vela en el Mediterráneo occidental. Mayoritariamente se han venido adscribiendo al I o finales del II milenio a.C. Este artículo ofrece nuevos calcos y datos para una mejor comprensión del conjunto de motivos del abrigo. Entre los resultados obtenidos planteamos cuestionar la anterior cronología. Las dataciones absolutas confirman su frecuentación entre el IV-III milenio a.C., durante el Neolítico Reciente y Calcolítico del sur de Iberia. Una época de importantes transformaciones en la región. Además, el resto de resultados obtenidos son leídos en términos de datación relativa (tipos de motivos, su contexto cultural, análisis de pigmentos mediante reflectancia óptica y superposición de figuras), no apartándose de las dataciones obtenidas. La distribución espacial de las figuras indica que los barcos ocupan el centro de la cavidad, son el tema principal de Laja Alta, el resto está determinado por la escena naval. Esta conclusión tiene implicaciones históricas para la transferencia de tecnologías, bienes e ideas que dieron forma a las sociedades del Neolítico Reciente y la Edad del Cobre de Europa occidental y norte de África.

Toarcian sections studied mainly in Europe have revealed the incidence of Milankovitch forcing with a well-developed, highly stable, 405 ky component of eccentricity, a short-term eccentricity of ~100 kyr, the cycle of obliquity ~36 kyr, and the precession signal at ~21 kyr. Cyclostratigraphic analysis of the Toarcian succession at the Valdorbia section (Umbria-Marche Apennines) was conducted based on time-series of foraminiferal assemblages. Well-developed cyclic patterns were obtained, with several significant cycles corresponding to thicknesses of 3.8-4.1 m / 5.8-6.3 m / 8.2 m / 10.4 m. Comparison with previous studies at the Valdorbia section led us to interpret the cycle of ~4 m as directly related with the short-term eccentricity (95-105 kyr). The rest of the cycles could be assigned to a periodicity of ~140-160 kyr, ~200 kyr and ~250 kyr, and interpreted as indirect signals of the long-term eccentricity, obliquity and precession, whose record would be impeded by the incompleteness of the studied succession and the sampling interval. Studied components in the foraminiferal assemblage show variable cyclostratigraphic patterns, allowing for a differentiation of groups based on similar registered cycles. These groups reveal different responses by the foraminiferal assemblage, associated with particular requirements, to the palaeoenvironmental changes of Milankovitch origin., Departamento de Estratigrafía y Paleontología, Universidad de Granada, España, Instituto Geológico y Minero de España, España, Departamento de Geología, Universidad de Jaén, España, Centre de Recherche sur la Paléodiversité et les Paléoenvironnements, Muséum National d’Histoire Naturelle, Francia, Centre de Recherche sur la Paléodiversité et les Paléoenvironnements, Université Pierre et marie Curie, Francia, Centre de Recherche sur la Paléodiversité et les Paléoenvironnements, Centre National de la Recherche Scientifique, Francia

IX Congreso Geológico de España, 12-14 septiembre 2016, Huelva.-- 4 pages, 4 figures, [EN] The Pleistocene deposits of the Faro Drift at sites U1386 and U1387 with IODP 339 Exp. 339 have been examined to characterize: a) their lithofacies, b) for identifying the most used useful criteria for distinguishing between contourites and gravity flow deposits, and c) to determinate the sediment provenance. Three lithofacies, contourites, turbidites and debrites are defined based on sedimentological and mineralogical results. The most useful criteria for distinguishing between these two deposits are: i) the grain size vertical trend and sedimentary structures; ii) the modal frequency distribution, and iii) the sediment composition. Interpretation of sediment provenance of the different lithofacies reflects modes of long- and short-distance transport. Most of the terrigenous sediment of contourites is coming from the distant Guadalquivir drainage basin whereas those terrigenous sediment of turbidites and debrites are sourced by the vicinity fluvial drainage basins, Guadiana and Tinto-Odiel and biogenous components indicating shallow marine depositional environments, [ES] Se analizan los depósitos del Pleistoceno de los sondeos U1386 y U1387 obtenidos en la Expedición 339 IODP en los depósitos (drift) de Faro para caracterizar: a) las litofacies, b) identificar los criterios más útiles para distinguir entre contornitas y depósitos de flujos por gravedad y c) determinar la procedencia de sedimentos. Se identifican tres litofacies, contornitas, turbiditas y debritas en base a resultados sedimentológicos y mineralógicos. Los criterios más útiles para distinguir entre estos dos tipos de depósitos son: i) la variación vertical del tamaño de grano y estructuras sedimentarias; ii) la distribución de la frecuencia modal y iii) la composición de los sedimentos. La mayoría del sedimento terrígeno de los depósitos contorníticos proviene de la cuenca del Guadalquivir mientras que los sedimentos terrígenos de turbiditas y debrites proceden de las cuencas fluviales de Guadiana, Tinto-Odiel y los componentes biogénicos sugieren que proceden de ambientes deposicionales marinos someros, Funding for this research was provided by Spanish Ministry of Economy and Competitiveness projects: MOWER (CTM 2012-39599-C03) and MONTERA (CTM2009-14157-C0-02)

Several hundred Aalenian Tmetoceras from the Iberian Peninsula (N Lusitanian Basin, Asturias, Basque-Cantabrian Basin, NE Cameros, NW Iberian Basin, Aragonese Platform, Tortosa Platform, Castilian Platform, Majorca and Betic Basin) have been reviewed. Two species of Aalenian Tmetoceras have been identified on the basis of morphological, biochronological and palaeobiogeographical data: T. scissum and T. regleyi. T. scissum was dominant among the Tmetoceras populations developed in the Betic and Lusitanian basins during Opalinum, Murchisonae and Bradfordensis biochrons. Populations composed by evolute individuals of T. scissum inhabited shelfal or oceanic environments. A chronocline, from rectiradiate and primitive forms to flexicostate and derived forms, can be recognized in these populations of T. scissum. In contrast, shallow epicontinental platforms were inhabited by involute individuals of T. regleyi. This second species was phyletically derived from T. scissum, representing an adaptive radiation from populations of shelfal or oceanic basins to populations of epicontinental platforms.