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En este trabajo se presenta el reto que muchas veces supone conseguir un buen modelo de edad independiente en una secuencia paleoambiental. Esta aproximación pasa por la necesidad de combinar diferentes metodologías de datación, con la complejidad que esto implica. Se han seleccionado dos ejemplos de dos archivos paleoambientales muy distintos, y con cronologías muy diferentes. El registro de El Cañizar de Villarquemado, un paleolago en la provincia de Teruel, que alberga en sus sedimentos los últimos 135.000 años de historia y constituye la secuencia continental más larga y continua estudiada en la mitad septentrional de Iberia. Para poder establecer un modelo de edad robusto e independiente fue necesario combinar dataciones de radiocarbono AMS, U-Th, OSL, IRSL, paleomagnetismo y criptotefro-cronología, aunque no todas las técnicas resultaron exitosas. El segundo ejemplo se centra en el reto de datar el hielo presente en el icónico glaciar de Monte Perdido, situado en el Pirineo Central, Huesca. Este registro se consiguió datar mediante radiocarbono en diferentes tipos de muestras y aplicando las técnicas de 210Pb y 137Cs para el periodo más reciente. En ambos ejemplos, las combinaciones de métodos y tipo de muestras datadas permitieron obtener cronologías robustas gracias a una importante inversión de tiempo y financiación, siendo el resultado de la colaboración de varios equipos de investigación. En este trabajo se esbozan las dificultades encontradas en la elaboración de ambas cronologías y se presenta el resultado final, fruto de una modelización que combina las diferentes aproximaciones para obtener los modelos de edad definitivos.

The Roca San Miguel (RSM) archaeological site was occupied during Mousterian times. Here we present a geoarchaeological and paleoenvironmental reconstruction of the site. Five stratigraphic units (A to E) formed by different archaeological levels are identified. Three optically stimulated luminescence (OSL) ages show that Unit A dates to between 169.6 ± 9.1 and 151.9 ± 11.1 ka, during the penultimate glacial period (PGP), and contains numerous signs of recurring hearths. Unit B is unexcavated. Unit C dates to between 118.9 ± 11.5 and 103.4 ± 6.9 ka (late Eemian–marine isotope stage (MIS) 5d) and shows an abundance of lithic remains as well as some faunal elements. Unit C is covered by Unit D, which incorporates materials moved downslope, and is dated at 81.2 ± 4.7 ka. These OSL ages concur with U/Th ages (129.3 ± 1.5 and 123.6 ± 0.6 ka) derived from a flowstone covered by both -C and Dpost-flowstone units. Finally, Unit E covers the archaeological site, which was partially eroded during MIS2. The robust and well-constrained chronology of the RSM site and surroundings enables the establishment of its evolutionary model from the PGP to the last glacial cycle. The RSM site is the oldest Neanderthal occupation accurately dated in the Pre-Pyrenean region., This research was supported by the Gaps and Sites (HAR2017-85023-P) and Gaps and Dates (PID2020-116598GB-I00) projects, funded by the MINECO/MICIN-AEI/FEDER, Spain/EU; and by the Research Group P3A from the Aragón Government (H14_20R).

Ice caves are one of the least studied parts of the cryosphere, particularly those located in inaccessible permafrost areas at high altitudes or high latitudes. We characterize the climate dynamics and the geomorphological features of Devaux cave, an outstanding ice cave in the Central Pyrenees on the French–Spanish border. Two distinct cave sectors were identified based on air temperature and geomorphological observations. The first one comprises well-ventilated galleries with large temperature oscillations likely influenced by a cave river. The second sector corresponds to more isolated chambers, where air and rock temperatures stay below 0 ∘C throughout the year. Seasonal layered ice and hoarfrost occupy the first sector, while transparent, massive perennial ice is present in the isolated chambers. Cryogenic calcite and gypsum are mainly present within the perennial ice. During winter, the cave river freezes at the outlet, resulting in a damming and backflooding of the cave. We suggest that relict ice formations record past damming events with the subsequent formation of congelation ice. δ34S values of gypsum indicate that the sulfate originated from the oxidation of pyrite present in the bedrock. Several features including air and rock temperatures, the absence of drips, the small loss of ice in the past 7 decades, and the location of ice bodies in the cave indicate that the cave permafrost is the result of a combination of undercooling by ventilation and diffusive heat transfer from the surrounding permafrost, reaching a thickness of ∼ 200 m.

[EN] Speleothems and detrital sequences are excellent archives of past flood events but are still poorly exploited. In this study we evaluate the potential of the Ojo de Valjunquera cave for the study of past floods based on geomorphological, topographical, hydrological, and chronological data. The cave presents two pseudo-horizontal cave levels. The lower presents a main horizontal conduit and six siphons. This level is connected to the upper one by shafts and ramps that favours the water level rise during rainfall events. The upper level is characterized by a major presence of speleothems and detrital sequences compared to the lower level. Current observations indicate that water can rise ~9 m in some cave sectors during rainfall episodes >60 mm, although the hydraulic head rise is not homogeneous along the cave, depending of section's morphology. The stalagmites and detrital sequences hosted in the upper gallery most likely contain evidence of extreme events of rainfall. However, geomorphological and sedimentological evidences also suggest that cave outlet could be blocked in the past by sediments, favouring the water rise of regular floods to high places not usually affected by floods. The detrital sequences located in lower positions respect to the cave entrance show a major proportion of sand than those located in the higher sectors related to the energy of the waters during the flood. Stalagmites show clean carbonate alternated with well-defined detrital layers. These detrital layers vary in thickness; the thin ones are related to small floods, whereas the thicker ones are related to large floods. Two important historical floods (1709 and 1755 CE) occurred in the area that coincide with distinct detrital layers recorded in the stalagmites. All these observations suggest that Ojo de Valjunquera cave contains an important paleoflood archive base on speleothems and detrital deposits during the Holocene., [ES] Los espeleotemas y secuencias detríticas de las cuevas contienen registros detallados de inundaciones del pasado, aunque han sido poco utilizadas para este fin. En este trabajo evaluamos, en base a observaciones geo-morfológicas, topográficas, hidrológicas y cronológicas, el potencial e idoneidad de la cueva Ojo de Valjunquera (Zaragoza, NE de España) para el estudio de inundaciones pasadas. La cueva tiene dos niveles pseudo-horizontales. El nivel inferior presenta un río y seis sifones. Este nivel está conectado al superior mediante pozos y rampas. Esa situación, además de las constricciones en la galería inferior, favorecen la subida del agua durante importantes eventos de lluvia. El nivel superior presenta una mayor cantidad de espeleotemas y secuencias detríticas que el nivel inferior. Las observaciones actuales indican que el agua puede subir aproximadamente 9 m en algunos sectores de la cueva durante episodios de precipitaciones acumuladas superiores a 60 mm. Sin embargo, la subida del nivel de agua parece no ser homogénea a lo largo de la cueva, dependiendo de la morfología de las diferentes secciones. De acuerdo a estas observaciones, las estalagmitas y secuencias detríticas registradas en la galería superior se asocian a eventos extremos de lluvia. Por otro lado, las evidencias geomorfológicas y sedimentológicas también sugieren que la salida de la cueva pudo estar bloqueada en el pasado por sedimentos, favoreciendo fácilmente el ascenso del agua durante inundaciones regulares, a zonas altas no inundadas frecuentemente. Las secuencias detríticas ubicadas en posiciones más bajas respecto a la entrada de la cueva muestran un mayor porcentaje de arena que las ubicadas en los sectores más altos, en relación a la energía de las aguas durante la crecida. Las estalagmitas presentan una alternancia de carbonato limpio y capas detríticas bien definidas. Las capas detríticas comprenden capas delgadas y gruesas, que parecen estar en relación con pequeñas y grandes inundaciones respectivamente. Dos importantes inundaciones históricas (1709 y 1755 DC) que ocurrieron en el área, parecen estar registradas en las estalagmitas. Todas estas observaciones hacen del Ojo de Valjunquera una cueva idónea y con alto potencial para la reconstrucción de paleoinundaciones y lluvias extremas a partir de espeleotemas y depósitos detríticos durante el Holoceno., This study was partially funded by SPYRIT (CGL 2016-77479-R) and PYCACHU (PID2019- 06050RB-100) national projects. M. Bartolomé is supported by a postdoctoral fellowship (Juan de la Cierva -Formación program) provided by the Spanish Ministry of Science (ref.: FJCI-2017-31725). Bartolomé is supported by a postdoctoral fellowship (Juan de la Cierva - Formación program) provided by the Spanish Ministry of Science (ref.: FJCI-2017-31725).

New speleothem records from northeastern Iberian caves provide data to explore the climatic patterns during the Holocene. We present δ13C and Mg/Ca from three speleothems from two different caves located in the Iberian Range allowing replication of the climatic signal for several millennia. Through the integration of those stalagmites covering since the Holocene onset to 2 ka, the early Holocene (11.7–8.5 ka) appears as the wettest interval. A marked change towards aridity is observed during the middle Holocene (8.5–4.8 ka) and an increase of humidity afterwards (4.8–2 ka). This three-part pattern, contrasting with other Iberian sequences, seems to be associated with the different role that seasonality has played in the response of different proxies (or records) to changes in water availability. Interpreting our speleothem records as changes in winter-spring precipitation along the Holocene allows reconciling previous data on hydrological variability from the western Mediterranean borderlands.

This work combines very detailed measurements from terrestrial laser scanner (TLS), groundbased interferometry radar (GB-SAR) and ground-penetrating radar (GPR) to diagnose current conditions and to analyse the recent evolution of the Monte Perdido Glacier in the Spanish Pyrenees from 2011 to 2017. Thus, this is currently one of the best monitored small glacier (

Sedimentological, geochemical and magnetic data in a ~ 7-m sequence from Marboré Lake (2612 m asl, central Pyrenees) provide information about environmental variability since the last glacier retreat (14.6 cal ka BP) in high-altitude Pyrenean environments. The sediment sequence is composed of millimeter- to centimeter-thick rhythmites made of finer greyish laminae and coarser-grain, carbonate-bearing laminae arranged in varied patterns throughout the sequence. Finer laminae are interpreted as deposition during periods of predominantly ice-covered conditions, whereas coarser, carbonate-bearing sediments reflect periods of higher runoff. The age model, based on 13 14C dates and a reservoir effect assessed with 210Pb and 137Cs, is coherent with known synchronous vegetation changes across the Pyrenees. Warmer intervals such as GI-1 (14.6–12.8 cal ka BP, Bølling/Allerød period), 10.4–8.2 cal ka BP in the Early Holocene, 7.5–5.2 cal ka BP in the Mid Holocene and the Medieval Climate Anomaly (AD 900–1300), are characterized by peaks in productivity and higher carbonate preservation. Deposition during colder periods such as GS-1 (12.8–11.7 cal ka BP), the Neoglacial (ca. 5.2–3.5 cal ka BP) and the Little Ice Age (last 400 years) show an increase in finer laminae. The presence of magnetite throughout the whole section suggests that Marboré Lake maintained predominantly oxic conditions since its formation. Changes in magnetic properties and the increase in magnetite from 3.5 cal ka BP to present, however, indicate a more oxic environment at the lake bottom during the last few millennia. The occurrence of Pb concentration peaks in sediments of Roman and modern age demonstrates the global distribution of heavy metal deposition, even into high-mountain lakes., Departamento de Geología y Geoquímica, Universidad Autónoma de Madrid, España, Departamento de Procesos Geoambientales y Cambio Global, Instituto Pirenaico de Ecología, España, Departamento de Procesos Geoambientales y Cambio Global, Consejo Superior de Investigaciones Científicas, España, Department of Geography and Earth Sciences, Aberystwyth University, Reino Unido, Departamento de Investigación en Recursos Geológicos, Instituto Geológico y Minero de España, España

The Seso Cave System (SCS, South Central Pyrenees, Northeastern Spain) develops in poorly soluble marly interstratum between limestone beds of Eocene age. We propose an innovative and singular pseudokarstic speleogenetic model under vadose conditions based on cave morphological evidence, physicochemical and mineralogical characteristics of the Eocene marly host rock, U-Th dating of cave deposits, and local geological and geomorphological information. Eocene marls are shown to be sensitive to dispersion processes supported by their high clay content and the high concentration of sodium and low electrical conductivity in the seepage water. Runoff inside the cave results from water that infiltrates through joints and seepage water in cave walls. Thereby piping processes become very active, triggering mechanical scouring and outwashing mechanisms. The hydraulic gradient required to develop piping activity is determined by regional fluvial incision. The base level controlling water discharge during opening of the SCS coincides with a terrace of the Ara River dated at 65. ka. BP. Considering this age, as well as the U-Th age of the oldest speleothems dated in the cave at 38. ka. BP, the timing of the SCS interstratal piping-cave speleogenesis is constrained to the Upper Pleistocene; very likely at the end of Marine Isotope Stage 4 during a period characterized by high water availability following glacial retreat in northern Iberian mountains. © 2014 Elsevier B.V., This research was funded by CGL2009-10455/BTE and CGL2010-16376 (HIDROPAST) projects of the Spanish Government (Ministerio de Ciencia e Inovación) and the European Regional Development Fund (FEDER) and a Sobrarbe Geopark research grant. It is a contribution of the PaleoQ Group (Aragón Regional Government). We thank Julie Retrum and Yanbin Lu (University of Minnesota) and Enrique Oliver (Universidad de Zaragoza) for the help in the laboratory work and Jaume Mas and Xavier Fuertes (Grupd'Espeleologia de Badalona) for field cave mapping support and Josu Aranbarri for Fig. 1 design.We appreciate very much the comments by Prof. Jo De Waele, an anonymous reviewer and Prof. Andrew J. Plater (Editor), which have improved the final version of the manuscript.

A paleomagnetic study has been carried out on a waterlaid detrital sedimentary sequence of ~240cm thick within the Seso Cave System (West-Central Pyrenees). In these sediments, seven charcoal samples were dated using 14C AMS ranging from 2080 to 650calyrBP (130BC-1300AD). Two levels of human occupation of the cave have been recognized by ceramics associated to the Iberian Period and to the Roman Period, respectively. The detrital sedimentary sequence is made of autochthonous (piping detached material from the Eocene marls host rock inside of the cavity) and allochthonous (stream transported sediments from the outside) sediments. The autochthonous material (first 100cm), made of fine grain laminated sediments (lutites and marls) corresponds to pond facies; the allochthonous material (190-240cm) is made of lutites and sands and corresponds to stream facies, and both facies are mixed from 100 to 190cm. The increase in sedimentation rate towards the end of the sequence (stream facies) points to an intensification of the alluvial activity as a possible consequence of a more arid climate during the Medieval Climate Anomaly. For the paleomagnetic study, 44 discrete cylindrical samples were taken along the detrital sequence. The values of the natural remanent magnetization and magnetic susceptibility are significantly lower in the pond sediments than in the stream sediments. The declination and inclination of the paleomagnetic characteristic component (sister samples analyzed by both alternating field and temperature demagnetizing procedure) of each depth point is compared to the Spanish archeomagnetic catalog and available geomagnetic models (ARCH3k.1, CALS3k.4, CALS10k.1b and SCHA.DIF.3K) in order to determine the accuracy of these sediments recording the Earth's magnetic field. Results suggest that these sediments poorly record the Earth's magnetic field, however, paleomagnetic inclination shows similar results between both demagnetizing methods and the inclination is well recorded especially in the younger stream facies. The lack of archeological remains with absolute dates from 925 to 1545calyrBP in the Iberian paleomagnetic secular variation reference curve has prevented, up to now, the study of that time period. Therefore, the inclination data from the Seso Cave deposit is the first record of the Iberian paleomagnetic secular variation during most part of the Medieval time, and they are closer to the inclination values of one geomagnetic model (CALS10k.1b). © 2014 Elsevier B.V., BOU acknowledges the JAEdoc Programme of CSIC, partly financed by the European Social Fund. All authors thank the financial support of the Instituto de Estudios Altoaragoneses, of the projects CGL2009-10455/BTE, HIDROPAST CGL2010-16376 (MICINN and FEDER), ORDESA (Autonomous Organism of National Parks), and the PaleoQ Group (Universidad de Zaragoza-Gobierno de Aragón). We are also indebted to Jaume Mas-Moiset and Xavier Fuertes from the Grup d'Espeleologia de Badalona (GEB) for the cartography of the cave system and field support. Dr. José Luis Peña-Monné and Dr. Fernando Pérez-Lambán are acknowledged for the classification and comments of pottery remnants. We are indebted to GEOMAGIA50, which is a database that comes with a web interface intended to give users easy access to archeomagnetic data (Donadini et al., 2006 and Korhonen et al., 2008). Comments and suggestions from two anonymous reviewers are deeply acknowledged.

38 Pags.- 8 Figs. The definitive version is available at: https://onlinelibrary.wiley.com/journal/10991530. This article was included into a special Special Issue: "Permafrost and Periglacial Processes in mid‐low latitude mountain regions"., Pedofeatures associated with ancient cold climatic conditions have been recognized in soils on terraces in the Monegros area (central Ebro Basin, Spain), at a latitude of 41°49′N and an altitude of 300 m a.s.l. Eleven soil profiles were described on fluvial deposits corresponding to the most extensive terrace (T5) of the Alcanadre River, Middle Pleistocene in age (MIS8–MIS7). Each soil horizon was sampled for physical, chemical, mineralogical and micromorphological analyses. Macromorphological features related to pedocryogenic processes were described: involutions, jacked stones, shattered stones, detached and vertically oriented carbonatic pendents, fragmented carbonatic crusts, laminar microstructures, succitic fabric, silt cappings on rock fragments and aggregates, and irregular, broken, discontinuous and deformed gravel and sandy pockets. Accumulations of Fe–Mn oxides, dissolution features on the surface of carbonatic stones, and calcitic accumulations were identified related to vadose–phreatic conditions. The observed periglacial features developed under cold environmental conditions in exceptional geomorphic and hydrological conditions. This soil information may have potential implications in studies of paleoclimate in the Ebro Valley as well as in other Mediterranean areas., This study was funded by the Spanish Ministry of Economy, Industry and Competivity under the projects CGL 2017-89603-R and PCI2018-092999.