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Extreme floods are anticipated to become more frequent in a future warmer climate. However, the long-term alterations in flood patterns across different regions of Europe remain unclear. In this study, we present a 15,000-year record of extreme floods in the Duero River, located in the southwestern Atlantic region. We analysed slackwater flood sediments, quantified the discharge and timing of individual flood beds over millennial time scales, and identified their potential climate influences. The composite record includes at least 62 floods grouped into ten flood-rich periods (with an average duration of 230 years). A high-frequency phase of moderate-magnitude floods (>10 events) occurred at ∼11.6–11.5 ka, following a period of reduced flood activity during the Younger Dryas. Similar clusters of Early Holocene floods (10.8–10.3 ka, 9.5 ka) coincided with or preceded meltwater pulses from the North Atlantic. The absence of palaeoflood records with discharges exceeding 6100 m3/s during the Mid-Holocene suggests a decline in winter hydro-meteorological extremes. High flood magnitudes were recorded during transition periods toward cooler and wetter conditions at 4.4, 2.3, 0.5, and 0.11 ka with discharges ranging from 7600 to 10,000 m3/s. These periods were interpreted as indicative of a southward shift in cyclone tracks in Europe driven by negative phases of the North Atlantic Oscillation (NAO). Conversely, flood magnitudes decreased during past warmer climate conditions (1.7 ka, 0.9 ka, and the present), although flood frequency remained high. The current decline in flood frequency reflects an increase in flood regulation due to dams, but it is also consistent with the prevailing positive trend in the NAO observed over the last 40 years., Ministerio de Ciencia e Innovación (España), Dirección General del Agua, Fundación Biodiversidad, Union Europea, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

The left-lateral Beata ridge (BR) and the right-lateral Ocoa-Bonao-La Guacara (OB) fault zones transfer the Plio-Quaternary deformation that results from the NNE-indentation of the Beata oceanic escarpment under the southern margin of Hispaniola. An arcuate relief bound the Ocoa bay, and the current tectonic uplift accelerates the fluvial incision and modifies the fluvial network. Both are active seismic faults whose respective kilometric traces converge 20 km northeaster ward of Ocoa bay, under the San José de Ocoa basin and potentially might be generated large earthquakes. In detail, strain is accommodated by the brittle partition of the fault zones and segmentation of the main faults into minor faults that bounded kilometric blocks of a lozenge shape, with the development of two significant partitions: the Sabana Buey pull-apart basin and the extensional block southward the Azua area; according to the respective fault topology and the relative fault rate displacement. The avulsion of the Ocoa river by the Sabana Buey basin opening occurred during the late Pleistocene, according to the OSL age of a lower alluvial fan (ca. 16 ky) incised by the current floodplain into the river mouth., Las zonas de fallas de desgarre izquierdo de la cresta de Beata (BR) y derecho de Ocoa-Bonao-La-Guácara (OB) transfieren la deformación Plio-Cuaternaria que produce la indentación NNE del escarpe oceánico de Beata bajo el margen meridional de la Española. La bahía de Ocoa está bordeada por un relieve arqueado, y el levantamiento tectónico actual acelera la incisión fluvial y modifica la red fluvial. Ambas fallas son sísmicamente activas y sus trazas kilométricas convergen 20 km hacia el noreste de la bahía de Ocoa, bajo la cuenca de San José de Ocoa, y potencialmente pueden generar grandes terremotos. En detalle, la deformación está acomodada por la partición frágil de las zonas de falla y la segmentación de las fallas principales en fallas menores que bordean bloques romboidales, con desarrollo de dos importantes particiones: la cuenca de “pull-apart” de Sabana Buey y el bloque extensional del S del área de Azua; de acuerdo con la respectiva topología de la zona de falla y las tasas de desplazamiento relativo. La avulsión del río Ocoa por la apertura de la cuenca de Sabana Buey se produjo en el Pleistoceno superior, de acuerdo con la datación OSL de la base de un abanico aluvial inferior (ca. 16 ka) incidido por la llanura aluvial de inundación actual en la desembocadura del río.

According to GPS measurements, the Caribbean plate is moving east-northeastward relative to the North American plate at a rate of ∼20 mm/a. This oblique motion is partly accommodated in southern Hispaniola by northward underthrusting/subduction bellow the Muertos submerged accretionary prism and the Peralta fold-and-thrust belt. This work investigates the active transition zone that connects Muertos and Peralta: the Ocoa-Bonao-La Guacara fault zone (OBFZ). Combined detailed structural analysis at macroscopic and mesoscopic scales, regional magnetic data and seismicity analysis, geomorphic observations, fault-slip data inversion and geochronology of Quaternary deposits allow to establish the deformation pattern for the OBFZ along southern central Hispaniola. Distinct tectonic regimes have occurred successively in the Neogene, within a consistent regional NE-trending horizontal shortening: (a) a lower Miocene to Early Pleistocene D1 regime characterized by SW-directed thrusting that homogeneously affects the region; and (b) an Early/Middle Pleistocene to Holocene D2 regime of strike-slip to transpressional faulting mainly located along the OBFZ. The change is coeval with the tectonic indentation of the Beata Ridge in the back-arc region of the Hispaniola microplate. Finally, a Late Pleistocene to Holocene D3 extensional regime has a local development around the Ocoa Bay. Part of the present-day stress-field induced by the Beata Ridge collision is accommodated by the OBFZ within the Hispaniola microplate. This fault zone defines the onland transition between oceanic subduction and arc-oceanic plateau collision. Due to its length and potential to generate large earthquakes, the OBFZ must be considered in the regional seismic hazard assessment.

In the Huelva Coast of SW Spain erosion by recent marine storms revealed the presence of a paleosol where an extensive tracksite known as “Matalascañas Trampled Surface” (MTS) has been documented. The MTS includes tracks and trackways of large species of mammals, along with bird trace fossils, invertebrate burrows and root traces. Within this record, the presence of several hominin footprints and trackways stands out. Despite previous uncertainties about the producer of these footprints, new OSL age of 151 ± 11 ka secures their attribution to Neanderthals, the only hominins known to have been present in the Iberian Peninsula during the MIS6-5 transition. Moreover, typical Mousterian lithic industry with Levallois knapping was found associated with the ichnological record. This lithic industry is characterized by the selection of raw materials from outcrops in a short-distance range to the tracksite. The general characteristics of the lithics are derived both from the nature of the raw material and from the nature of the site itself, which cannot be seen as a settlement, but rather as a place of passage for fauna, including Neanderthals, where a few human individuals performed short-term activities, such as food procurement and/or meat processing.

[EN] This dataset present methodological, seismic, structural and geochronological (optically stimulated luminescence) data collected in southern central Hispaniola Island to better understand the regional process of collision between the Beata Ridge and the back-arc margin of the Caribbean island-arc. In particular, the role played by the Ocoa-Bonao-La Guacara fault zone (OBGFZ), which is an active, NNE to NE-striking large-scale fault system that crosses the southern central sector of Hispaniola in the Dominican Republic along more than 250 km.

[EN] According to GPS measurements, the Caribbean plate is moving east-northeastward relative to the North American plate at a rate of ~20 mm/a. This oblique motion is partly accommodated in southern Hispaniola by northward underthrusting/subduction bellow the Muertos submerged accretionary prism and the Peralta fold-and-thrust belt. This work investigates the active transition zone that connects Muertos and Peralta: the Ocoa-Bonao-La Guacara fault zone (OBFZ). Combined detailed structural analysis at macroscopic and mesoscopic scales, regional magnetic data and seismicity analysis, geomorphic observations, fault-slip data inversion and geochronology of Quaternary deposits allow to establish the deformation pattern for the OBFZ along southern central Hispaniola. Distinct tectonic regimes have occurred successively in the Neogene, within a consistent regional NE-trending horizontal shortening: (1) a lower Miocene to Early Pleistocene D1 regime characterized by SW-directed thrusting that homogeneously affects the region; and (2) an Early/Middle Pleistocene to Holocene D2 regime of strike-slip to transpressional faulting mainly located along the OBFZ. The change is coeval with the tectonic indentation of the Beata Ridge in the back-arc region of the Hispaniola microplate. Finally, a Late Pleistocene to Holocene D3 extensional regime has a local development around the Ocoa Bay. Part of the present-day stress-field induced by the Beata Ridge collision is accommodated by the OBFZ within the Hispaniola microplate. This fault zone defines the onland transition between oceanic subduction and arc-oceanic plateau collision. Due to its length and potential to generate large earthquakes, the OBFZ must be considered in the regional seismic hazard assessment.

The scientific study of Neolithic monuments holds fundamental keys to the analysis of early social complexity. This is often impeded by the challenges involved in understanding their temporality and, particularly, their initial construction dates. This problem is most severe in monuments that were not predominantly used for burial and went on to have long biographies in which activity in later periods obliterated the material record of the earliest phases. That was certainly the case of the Menga dolmen, part of the Antequera World Heritage site (Málaga, Spain), and one of the most remarkable megaliths in Europe, for which, after nearly 200 years of explorations and research, no firm chronology existed. The research presented in this paper shows how this problem was tackled through a multimethod, scientific, and geoarchaeological approach. The analysis of 29 fresh numerical ages, including radiocarbon determinations as well as optically stimulated luminescence, thermoluminescence, and uranium-thorium dates, led to the successful establishment of Menga’s construction date and the subsequent contextualization of the monument within the social and cultural background it arose in. Placing the dolmen in the context of its time of “birth” introduces entirely new possibilities for its interpretation, both in terms of local and supralocal social and cultural processes.

The BRITICE-CHRONO consortium of researchers undertook a dating programme to constrain the timing of advance, maximum extent and retreat of the British–Irish Ice Sheet between 31 000 and 15 000 years before present. The dating campaign across Ireland and Britain and their continental shelves, and across the North Sea included 1500 days of field investigation yielding 18 000 km of marine geophysical data, 377 cores of sea floor sediments, and geomorphological and stratigraphical information at 121 sites on land; generating 690 new geochronometric ages. These findings are reported in 28 publications including synthesis into eight transect reconstructions. Here we build ice sheet-wide reconstructions consistent with these findings and using retreat patterns and dates for the inter-transect areas. Two reconstructions are presented, a wholly empirical version and a version that combines modelling with the new empirical evidence. Palaeoglaciological maps of ice extent, thickness, velocity, and flow geometry at thousand-year timesteps are presented. The maximum ice volume of 1.8 m sea level equivalent occurred at 23 ka. A larger extent than previously defined is found and widespread advance of ice to the continental shelf break is confirmed during the last glacial. Asynchrony occurred in the timing of maximum extent and onset of retreat, ranging from 30 to 22 ka. The tipping point of deglaciation at 22 ka was triggered by ice stream retreat and saddle collapses. Analysis of retreat rates leads us to accept our hypothesis that the marine-influenced sectors collapsed rapidly. First order controls on ice-sheet demise were glacio-isostatic loading triggering retreat of marine sectors, aided by glaciological instabilities and then climate warming finished off the smaller, terrestrial ice sheet. Overprinted on this signal were second order controls arising from variations in trough topographies and with sector-scale ice geometric readjustments arising from dispositions in the ge

Luminescence dating has become a key tool in studies of the Quaternary. The typically stable luminescence response of quartz grains and the absence of a significant internal dose, make quartz minerals the preferred dosimeter for monitoring the burial dose in sediments. Unfortunately, the reliability of conventional OSL (optically stimulated luminescence) dating, based on blue stimulation, can be compromised when the luminescence decay is not dominated by a rapidly decaying and stable part of the luminescence signal (i.e. the fast component). On the other hand, standard methods in luminescence dating are limited to ages of a few hundred kiloyears. In this study, violet stimulated luminescence (VSL) has been used as a means to overcome both problems, applied to a series of colluvial deposits in the Atacama Desert, Chile. Quartz from this region, characterized by poor blue-OSL response, showed a reproducible and stable VSL signal capable of recovering given doses up to -500 Gy and a saturation dose twice as high as conventional OSL. The VSL response from these samples has been studied in detail and the estimated ages have been compared with an already established chronology for the same site, based on IRSL of potassium feldspar single grains. Results agree for the dose range of the profile studied, -100-250 Gy, equivalent to ages of 29-79 ka confirming the suitability of VSL for dating sedimentary quartz with unreliable blue-OSL response and to extend the age range of conventional OSL dating.

Olduvai Gorge (Tanzania) is a key site for the study of human evolution as well as the origin of modern humans and the Middle Stone Age (MSA). In this study, we present a new MSA location named Dorothy Garrod Site (DGS), found in the main branch of Olduvai Gorge. The site has only one archaeological level, located stratigraphically in the Upper Ndutu. Although it has not yet been possible to radiometrically date it, it has yielded numerous archaeological remains with a functional association between the faunal remains and the lithic industry. The fauna identifed includes Alcelaphini, Hippotragini, and Equidae, some of which present percussion marks and evidence of burning. The lithic industry involved knapping using discoid methods. The retouched blanks are denticulates and retouched fakes with, up to now, a total absence of points. DGS is therefore a new site that will aid our understanding of modern human occupations in northern Tanzania in a period for which there is a dearth of properly contextualised archaeological evidence.

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.

The findings of BRITICE-CHRONO Transect 2 through the North Sea Basin and eastern England are reported. We define ice-sheet marginal oscillation between -31 and 16 ka, with seven distinctive former ice-sheet limits (L1-7) constrained by Bayesian statistical analysis. The southernmost limit of the North Sea Lobe is recorded by the Bolders Bank Formation (L1; 25.8-24.6 ka). L2 represents ice-sheet oscillation and early retreat to the northern edge of the Dogger Bank (23.5-22.2 ka), with the Garret Hill Moraine in north Norfolk recording a significant regional readvance to L3 at 21.5-20.8 ka. Ice-marginal oscillations at similar to 26-21 ka resulted in L1, L2 and L3 being partially to totally overprinted. Ice-dammed lakes related to L1-3, including Lake Humber, are dated at 24.1-22.3 ka. Ice-sheet oscillation and retreat from L4 to L5 occurred between 19.7 and 17.3 ka, with grounding zone wedges marking an important transition from terrestrial to marine tidewater conditions, triggered by the opening of the Dogger Lake spillway between 19.9 and 17.5 ka. L6 relates to ice retreat under glacimarine conditions and final ice retreat into the Firth of Forth by 15.8 ka. L7 (-15 ka) represents an ice retreat from Bosies Bank into the Moray Firth. Copyright (C) 2021 The Authors Journal of Quaternary Science Published by John Wiley & Sons Ltd

Predicting the future response of ice sheets to climate warming and rising global sea level is important but difficult. This is especially so when fast‐flowing glaciers or ice streams, buffered by ice shelves, are grounded on beds below sea level. What happens when these ice shelves are removed? And how do the ice stream and the surrounding ice sheet respond to the abruptly altered boundary conditions? To address these questions and others we present new geological, geomorphological, geophysical and geochronological data from the ice‐stream‐dominated NW sector of the last British–Irish Ice Sheet (BIIS). The study area covers around 45 000 km2 of NW Scotland and the surrounding continental shelf. Alongside seabed geomorphological mapping and Quaternary sediment analysis, we use a suite of over 100 new absolute ages (including cosmogenic‐nuclide exposure ages, optically stimulated luminescence ages and radiocarbon dates) collected from onshore and offshore, to build a sector‐wide ice‐sheet reconstruction combining all available evidence with Bayesian chronosequence modelling. Using this information we present a detailed assessment of ice‐sheet advance/retreat history, and the glaciological connections between different areas of the NW BIIS sector, at different times during the last glacial cycle. The results show a highly dynamic, partly marine, partly terrestrial, ice‐sheet sector undergoing large size variations in response to sub‐millennial‐scale climatic (Dansgaard–Oeschger) cycles over the last 45 000 years. Superimposed on these trends we identify internally driven instabilities, operating at higher frequency, conditioned by local topographic factors, tidewater dynamics and glaciological feedbacks during deglaciation. Specifically, our new evidence indicates extensive marine‐terminating ice‐sheet glaciation of the NW BIIS sector during Greenland Stadials 12 to 9 – prior to the main ‘Late Weichselian’ ice‐sheet glaciation. After a period of restricted glaciation

The offshore sector around Shetland remains one of the least well‐studied parts of the former British–Irish Ice Sheet with several long‐standing scientific issues unresolved. These key issues include (i) the dominance of a locally sourced ‘Shetland ice cap’ vs an invasive Fennoscandian Ice Sheet; (ii) the flow configuration and style of glaciation at the Last Glacial Maximum (i.e. terrestrial vs marine glaciation); (iii) the nature of confluence between the British–Irish and Fennoscandian Ice Sheets; (iv) the cause, style and rate of ice sheet separation; and (v) the wider implications of ice sheet uncoupling on the tempo of subsequent deglaciation. As part of the Britice‐Chrono project, we present new geological (seabed cores), geomorphological, marine geophysical and geochronological data from the northernmost sector of the last British–Irish Ice Sheet (north of 59.5°N) to address these questions. The study area covers ca. 95 000 km2, an area approximately the size of Ireland, and includes the islands of Shetland and the surrounding continental shelf, some of the continental slope, and the western margin of the Norwegian Channel. We collect and analyse data from onshore in Shetland and along key transects offshore, to establish the most coherent picture, so far, of former ice‐sheet deglaciation in this important sector. Alongside new seabed mapping and Quaternary sediment analysis, we use a multi‐proxy suite of new isotopic age assessments, including 32 cosmogenic‐nuclide exposure ages from glacially transported boulders and 35 radiocarbon dates from deglacial marine sediments, to develop a synoptic sector‐wide reconstruction combining strong onshore and offshore geological evidence with Bayesian chronosequence modelling. The results show widespread and significant spatial fluctuations in size, shape and flow configuration of an ice sheet/ice cap centred on, or to the east of, the Orkney–Shetland Platform, between ~30 and ~15 ka BP. At its maximum extent ca. 26–25