Articles publicats en revistes (Dinàmica de la Terra i l'Oceà)

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North Atlantic Ocean–Atmosphere Dynamics Controlled theHydroclimate in Western Iberia During the Holocene
(John Wiley & Sons, 2026-09-08) Trigo, R.M.; Ramos, A.M.; Hernández, Agustín; Fernández‐Pérez, U.; Santos, R. N.; Rodrigues, T.; Schefuß, E.; Bao, R.; Raposeiro, P. M.; Sáez, Alberto; Giralt Romeu, Santiago; Martín‐Puertas, C.; Francus, P.
Hydroclimate variability in western Iberia during the Holocene remains insufficiently resolved despite the high sensitivity of this region to the North Atlantic atmosphere and ocean dynamics. Here, we present the first source-resolved reconstruction of centennial- to millennial-scale moisture variability over the last 11,000 years using sediments from Lake Peixão (Portugal) based on compound-specific hydrogen and carbon isotopes of plant wax n-alkanes, supported by bulk organic geochemistry and continuous X-ray fluorescence elemental data. Terrestrial source-resolved isotope series, obtained using non-negative matrix factorization, primarily reflect precipitation isotopic composition and plant water use efficiency. The record indicates a wet early Holocene, a progressive mid-Holocene drying trend that culminated in maximum aridity at approximately 4,000 calibrated years before present, and a transition to generally wetter but more variable late Holocene conditions, partly overprinted by anthropogenic land-use change. These trends are interpreted as reflecting orbitally driven changes in Northern Hemisphere insolation that modified the latitudinal temperature gradient (LTG) and, in turn, influenced the North Atlantic storm track position and intensity. Enhanced early Holocene moisture reflects a higher LTG and southward-displaced storm tracks, whereas mid-Holocene aridity corresponds to a reduced LTG and northward-shifted westerlies. The late Holocene recovery of wetter conditions agrees with a higher LTG and increased storm-track influence over Iberia. Superimposed centennial-scale variability likely reflects changes in North Atlantic Oscillation phases, the position of the Azores Front, and the intensity of the subpolar gyre. These results demonstrate the dominant roles of the LTG and coupled ocean–atmosphere dynamics in shaping the western Iberian hydroclimate throughout the Holocene.
Telescopic alluvial fans and pleistocene-holocene temporary lakes in the quebradas del Río Toro and Tastil (Salta, NW Argentina): main sedimentary features
(Springer, 2025-02-13) Colombo, Ferran; Salfity, José Antonio; Sánchez, María Cristina
[en] The Toro and Tastil Quebradas (river valleys) present different terrace-like geoforms made up of deposits of coarse-grained clastic materials. These terraces display convex-upward surfaces, a highly variable distribution, have a small lateral extension and depend on the lithology of the geological basement, which differs significantly along the quebradas. The number of terraces between one area and another indicates that these terraced geoforms should not be ascribed to one single cause, but rather to a variety of factors, i.e. local variations at base-level. The coarse-grained materials of the terraces are usually arranged in roughly horizontal layers that characterize the outcrops. These are interfingered with fine-grained mud-rich materials. The freshwater gastropod remains in the mud-rich materials indicate that they accumulated in lacustrine-like sedimentary environments. These developed from alluvial fans that spread out from the lateral quebradas to occupy the entire main valley (quebrada), giving rise to natural dams and temporary lakes upstream. Absolute data obtained by radiocarbon ( 14 C) methods strongly suggest that the alluvial fans were coeval with the temporary lakes in the Upper Pleistocene - Middle Holocene. The El Niño Southern Oscillation (ENSO) effects could have brought about the local variations in base-level that generated the younger temporary lakes, whereas the older ones were probably controlled by precession cycles (at about 21,000 y). The large number of temporary lakes scattered across the region suggests the overlapping of forcing factors at local and regional scales.
Inheritance in shortening transfer and kinematics in fold-and-thrust belts: Revisiting the structure of the Jaca Basin, Southern Pyrenees
(Elsevier B.V., 2025-11-01) Muñoz, J. A.; Izquierdo-Llavall, Esther; Santolaria, Pablo; Toro, Rocío; Pueyo, Emilio; Casas, Antonio M.; Granado, Pablo
This study revisits the structural evolution of the Jaca Basin in the Southern Pyrenees through a revision of the works done in the study area combined with a detailed analysis of geological and subsurface data, culminating in a new balanced cross-section. Our findings demonstrate that the propagation of the deformation into the foreland, from the basement to the cover, is heavily influenced by the uneven distribution of the Upper Triassic salt layer, at the base of the deformed Mesozoic-Paleogene succession, and the reactivation of Permian and Triassic extensional faults. This has led to a distinctive non-cylindrical fold-and-thrust belt with frictional and viscous domains displaying different structural styles. In the frictional domains, where Triassic salt is absent, high-angle thrust systems with a short wavelength involve both the basement and overlying strata, resulting in tight folds and related cleavage. In contrast, in the viscous domains where salt is preserved, deformation structures involving the cover succession are decoupled from the basement and propagate further into the foreland. Nevertheless, structures of both domains, independently of their location and geometry, tended to connect and link, resulting into an intricate thrust system with the development of numerous oblique structures. These oblique structures are further accentuated by the reactivation of inherited Permian and Triassic extensional faults, primarily involving basement thrusts. Differences in the topography between the frictional and viscous domains have also influenced the deposition and routing of syntectonic sediments, which in their turn have also determined the thrusting sequence. The evolutionary sequence of thrusting initiated in the late Ypresian and continued into the early Neogene. Contrary to previous models that suggested simply piggy-back propagation, our findings indicate a complex pattern of synchronous and break-back thrusting sequences with continuous forward propagation of the deformation. Detailed field work supports thrusting ages older than previously thought and indicates a greater amount of shortening (approximately 58 km) than earlier estimates. This comprehensive integration of surface and subsurface data challenges traditional interpretations and provides new insights into the structural evolution of the Southern Pyrenees. Our study highlights the importance of considering three-dimensional structural interactions in understanding tectono-sedimentary relationships. These insights into the complex structural geometry of the Jaca Basin enhance our understanding of similar salt-bearing fold-and-thrust belts globally, such as Zagros, Western Alps, Calcareous Alps, among many others, emphasizing the critical role of inherited geological features and uneven salt distribution in shaping orogenic systems.
Sediment provenance and transport pathways along the Atlantic Iberian Margin
(Elsevier B.V., 2026-02-15) Campderrós Serra, Sara; Pena Gonzalez, Leopoldo David; Garcia Solsona, Ester; Paredes, Eduardo; Català, Albert; Frigola Ferrer, Jaime I.; Haghipour, Negar; Cacho Lascorz, Isabel
The Atlantic Iberian margin is a dynamic region where oceanographic processes interact with continental sediment, influencing transport and deposition. To identify sediment sources and dominant transport dynamics we combine 87Sr/86Sr and ƐNd measurements on terrigenous sediments and 14C dating of planktonic foraminifera from core-tops along the margin. We present a new dataset of Sr-Nd isotope data from the Iberian Peninsula to characterize the isotopic composition of main river basins, considered potential sediment sources alongside African dust. By solving a ternary isotope mixing system, combined with a new statistical method to account for endmember isotopic distributions, we quantify the relative contribution of source areas to our samples. Our results reveal: 1) the margin is characterized by three isotopically distinct regions, 2) African dust is an important component of the terrigenous sediment (∼60 %), 3) regional differences in isotopic values reflect the influence of major river discharges: Guadalquivir in the south, Tagus in the centre, and Douro in the north, and 4) sediment transport follows a net northward direction along-slope. This sediment transport is attributed to the northward-flowing Mediterranean Outflow Water (MOW), which entrains and redistributes sediments along-slope. This is further supported by foraminifera 14C results, showing older radiocarbon ages along the MOW path, indicating sediment erosion. In contrast, younger radiocarbon ages are consistently found below MOW depths. The combined 87Sr/86Sr, ƐNd and 14C data suggest that MOW flow reduces sediment deposition along its path, transporting sediments northward, where it predominantly settles below the interface between MOW and the underlying North East Atlantic Deep Water.
Unique GNSS data from the Eastern Betic Tectonic Arc (western Mediterranean), covering almost 28 years of campaign observations
(Elsevier, 2026-07-01) Khazaradze, Giorgi; Alfaro, Pedro; García-Tortosa, Francisco Juan; Gil-Cruz, Antonio; Jacobo Quiñones, Noemi; Martin-Rojas, Iván; Medina-Cascales, Iván; Rodríguez Collantes, David
A unique dataset of GNSS observations from the SE Spain covering 28-years of campaign-style observations from 1997 to 2024 is presented. The data are compiled for the geo- logic study of Eastern Betic Tectonic Arc, where the calcu- lated present-day crustal deformation field shows significant motions ranging from 0 to 2 mm/yr with a dominant NNW-SSE orientation with respect to stable Eurasia. The presented dataset is subdivided into 3 subsets, depending on the au- thorship. All the data are presented in a standard RINEX: The Receiver Independent Exchange Format, version 2.11. The data interpretation is provided in the accompanying research paper and the data are deposited in Zenodo repository.
Upper Eocene-Oligocene larger Foraminifera from the westernmost Tethys (Prebetic Range, SE Iberia). Revision of Austrotrillina and Risananeiza
(Association Carnets de Géologie, 2026-08-08) Ferràndez i Cañadell, Carles; Granero, Paula; Bover-Arnal, Telm
The study of upper Eocene-Oligocene larger foraminiferal assemblages in two sections of the Prebetic Range in south-eastern Iberia (Ibi and La Font Roja sections) revealed a rich diversity, including species previously known only from the Central Tethys, such as the Eocene Neorhipidionina cf. spiralis, and the Oligocene Pfendericonus globulus, Austrotrillina howchini, Idalina pignattii, and Archaias sp., as well as endemic forms such as Peneroplis peramplus, Spirolinella emmae, and Borelis sp. 1. The continuous record of Austrotrillina (Rupelian-Chattian) and Risananeiza (upper Chattian) showed evolutionary trends and allowed for a systematic revision. Austrotrillina asmariensis, A. striata, and A. brunni are considered morphotypes of a single species, A. striata, evolving anagenetically from the lower Rupelian A. paucialveolata, which originated from the Eocene A. eocaenica. The two known species of Risananeiza, R. crassaparies and R. pustulosa, were identified for the first time within the same stratigraphic section. They represent successive stages of an anagenetic species throughout the upper Chattian. The biostratigraphic results provide an improved characterization of Shallow Benthic zones SB 21 to 23 in the westernmost Tethys and allow the subdivision of SB 23 (upper Chattian) into two sub-biozones, 23A and 23B, based on the stratigraphic ranges of miogypsinids (Miogypsinella spp., Postmiogypsinella intermedia) and Risananeiza. The Priabonian-Chattian Neorotalia burdigalensis also exhibits evolutionary trends with potential biostratigraphic relevance. Overall, the biostratigraphic data obtained indicate diachronous, parallel evolution and extinction in several genera, improving our understanding of diversity patterns and migration pathways in Oligocene larger Foraminifera.
North Atlantic response to a quasi-realistic Greenland meltwater forcing in eddy-rich EC-Earth3P-VHR hosing simulations
(European Geosciences Union (EGU), 2026-07-30) Martin-Martinez, Eneko; Moreno-Chamarro, Eduardo; Goldsworth, Fraser William; von Storch, Jin-Song; Arumi, Cristina; Kuznetsova, Daria; Loosveldt-Tomas, Saskia; Bretonnière, Pierre-Antoine; Ortega, Pablo
The vast majority of studies examining the impact of freshwater from ice sheet melting on the Atlantic Meridional Overturning Circulation (AMOC) use climate models that cannot resolve mesoscale ocean processes and do not include an accurate spatio-temporal distribution of the freshwater forcing. These two factors critically affect the nature of the AMOC response. Our study partially fills that gap with a set of three hosing experiments using perpetual 1950 radiative forcing with the global configuration of the eddy-rich EC-Earth3P-VHR climate model. The model is forced for 21 years with a spatial and monthly distribution of Greenland meltwater fluxes derived from a product based on observations and model simulations. An annual average close to 0.04 Sv is released on top of the simulated model river runoff, which is vertically distributed in the coastal points connected to each hydrological basin.Within the first year, we observe a response of reduced salinity in the Greenland and Labrador currents. Since the beginning of the experiments, these boundary currents also experience an acceleration and cooling. The cooling arises because freshwater-induced stratification suppresses vertical mixing, reducing the entrainment of warmer subsurface waters into the surface layer of the boundary currents. The meltwater fluxes also lead to a rapid weakening of the AMOC at subpolar latitudes due to circulation adjustments forced by the changes in density gradients, with the salinity-driven density reduction outweighing the temperature-driven density increase. Around year 7, deep mixing in the Labrador Sea begins to weaken as freshwater anomalies accumulate through lateral exchanges with the boundary currents. This weakening in deep mixing affects the Deep Western Boundary Current (DWBC), which warms up at the OSNAP section, and sequentially further weakens the AMOC, resulting in an even stronger reduction that reaches also the subtropical latitudes. After the 21 simulated years, the AMOC has weakened by almost 3 Sv at 60.2° N in density space, which represents a ∼20 % reduction of the climatological value in the control, 14.9 Sv. In the context of the North Atlantic, a basin-wide decrease of 1.3 Sv is measured between 10–65° N, which represents about 10 % reduction of the control reference, 13 Sv. This AMOC reduction is strong enough for some global climate impacts to emerge, such as a “bipolar seesaw” temperature response.
Effect of horizontal resolution in North Atlantic mixing and ocean circulation in the EC-Earth3P HighResMIP simulations
(European Geosciences Union (EGU), 2025-08-19) Martin-Martinez, Eneko; Frigola, Amanda; Moreno-Chamarro, Eduardo; Kuznetsova, Daria; Loosveldt-Tomas, Saskia; Samsó Cabré, Margarida; Bretonnière, Pierre-Antoine; Ortega, Pablo
We investigate the impact of increasing horizontal model resolution on the oceanic mixing processes in the North Atlantic, their drivers, their link with the Atlantic Meridional Overturning Circulation (AMOC), and the propagation of newly generated dense waters through the deep western boundary current (DWBC). We use three versions of the EC-Earth Earth system model, one of standard resolution (SR, ∼1° in the ocean), one of high resolution (HR, ∼0.25° in the ocean), and one of very high resolution (VHR, ° in the ocean). The higher resolutions allow for the explicit simulation of mesoscale processes that are parameterised at the coarse resolution, with additional improvements in ocean topography, boundary currents, and air–sea interactions. We find that the North Atlantic Oscillation plays a critical role in driving the mixed layer depth (MLD) in the Labrador Sea at HR and VHR. The three model configurations also show the influence of surface salinity signals in the mixing, with the VHR configuration showing a distinct slow propagation of these signals from the eastern subpolar gyre into the Labrador Sea. Furthermore, March MLD shows a strong positive bias in HR, which is reduced in VHR. In terms of the AMOC, resolution plays a pivotal role in shaping its response to the mixing. At the highest resolutions, the signal of the newly formed dense waters propagates faster along the better-resolved boundary current, indicating a shift from advective propagation to wave propagation of the signals. Additionally, the persistence of the AMOC responses to MLD is much shorter in VHR (less than 2 years) than for SR and HR, which exhibit longer-lived changes. These differences highlight how resolution affects both the timing and spatial reach of the AMOC changes. Our study underscores the importance of model resolution in accurately simulating the North Atlantic's oceanic processes and their implications for the AMOC. While the VHR configuration offers a more realistic climatology of the Labrador Sea MLD, the results also demonstrate significant differences in variability and persistence across resolutions. These findings stress the need for high-resolution simulations to improve the understanding of deep ocean processes and their connection to larger climate systems, although they also highlight challenges in comparing simulated and observed data, particularly given the sparse historical observations and the lack of decadal variability in the model simulations.
Offline Fennel: A high-performance and computationally efficient biogeochemical model within the Regional Ocean Modeling System (ROMS)
(European Geosciences Union (EGU), 2025-09-11) Crespin, Julia; Solé Blanch, Jordi; Canals Artigas, Miquel
Ocean biogeochemical models are essential for advancing our understanding of oceanographic processes. Here, we present the Offline Fennel model, a biogeochemical model that relies on previously computed physical fields, within the Regional Ocean Modeling System (ROMS). We evaluated the model performance against a fully coupled physical–biogeochemical online application in the northern Gulf of Mexico, a region with intense biogeochemical activity, including rather frequent hypoxia events. By leveraging physical hydrodynamic outputs, we ran the Offline Fennel model using various time-step multiples from the coupled configuration, significantly enhancing computational efficiency and reducing simulation computational time by up to 87 %. The accuracy of the offline model was assessed using three different mixing schemes: the generic length scale (GLS), Large–McWilliams–Doney (LMD), and Mellor and Yamada 2.5 (MY25). The offline model achieved an average skill score of 93 %, with minimal impact on performance from the time-step choice. While the GLS configuration yielded the highest accuracy, all three mixing schemes performed well. Although some discrepancies appeared between offline and coupled simulation outputs, these were smaller than those observed when using different mixing schemes within the same model configuration. A significant challenge identified was the simulation of ammonium (NH4), which exhibited the largest discrepancies due to its rapid-turnover timescale compared to other tracers. The promising results achieved so far validate the Offline Fennel model's capability and efficiency, thus offering a powerful tool for researchers aiming to conduct extensive biogeochemical simulations without rerunning the hydrodynamic component, thus significantly reducing computational demands.
New age constraints for glacial terminations IV, III, and III.a based on western Mediterranean speleothem records
(European Geosciences Union (EGU), 2025-02-14) Torner Perez, Judit; Cacho Lascorz, Isabel; Stoll, Heather; Moreno Caballud, Ana; Grimalt Obrador, Joan; Sierro Sánchez, Francisco Javier; Fornós, Joan J. (Joan Josep); Cheng, Hai; Edwards, R. Lawrence
The full understanding of climate feedbacks responsible for the amplification of deglaciations requires robust chronologies for these climate transitions, but in the case of marine records, radiocarbon chronologies are possible only for the last glacial termination. Although the assumed relationships between the marine isotopic record and the orbital parameters provide a first-order chronology for glacial terminations, an independent chronological control allows the relationships between orbital forcing and the climate response to be evaluated over multiple previous terminations. To assess this, we present geochemical records from the western Mediterranean, including two speleothems and one marine sediment core. The most notable speleothem, the so called RAT, established a new long terrestrial climate record for this region, spanning Marine Isotope Stages from MIS 11 to MIS 7. Its absolute U / Th dates provide an exceptional chronology for the glacial terminations IV, III, and III.a. The onset of these three glacial terminations was marked by rapid δ18O depletions, reflecting ocean freshening by ice melting, thus providing an excellent tie point for regional marine records also sensitive to such freshening. This is exemplified by new δ18O data of the Ocean Drilling Program (ODP) 977 site from the Alboran Sea, where the speleothem chronology was employed to adjust its age model. The new chronologies reveal an earlier onset of the deglacial melting for the TIV and TIII.a that is in contrast to the generally accepted marine chronologies and indicates that the duration of these deglaciations was variable, with TIV being particularly longer (∼ 20 kyr). This study also supports that the onset of deglacial melting always occurred during a declining precession index, while a nonunique relation occurred with the obliquity parameter.
Macrolitter accumulation in tidal marsh wrack deposits in a large estuary
(Elsevier Ltd., 2026-05-04) Garcés Ordóñez, Ostin; Canals Artigas, Miquel; Noyce, Genevieve; Rovai, André; Collin, Rachel; Thiel, Martin
Wrack refers to debris deposited along the upper intertidal zone by waves and tides. In the past, wrack consistedmainly of natural debris, but modern wrack includes anthropogenic macrolitter (AML). When AML is abundant,wracks become pollution hotspots that threaten ecosystem functioning. Here, we assess AML abundance, composition,and sources in wrack deposits from 27 tidal-marsh sites in the Chesapeake Bay estuary (USA) and examinerelationships with surrounding urban pressure and marsh conditions. Marsh wrack deposits in the estuary aredominated by wood, Phragmites, and marine macrophyte debris. AML abundance and mass range from 56 to4481 items km−1 and 0.9 to 254 kg km−1 of wrack, with highest values in the inner estuary. Both variables decreasewith increasing distance from main population centers. Marshes with higher vegetation density index alsohave high AML pollution. Most AML (93.5%) is positively buoyant, predominantly made of plastic (90%), andsmall (2–25 cm: 74.5%). Items are mainly plastic bottles and fragments, with a lifetime of <1-year. Older bottles(4 to >10 years-old) dominate the inner estuary, whereas newer bottles (<1 year-old) dominate the outer estuary.Food-consumption (38.9%) and fisheries (6.2%) related items are most prevalent. Over half of the AMLcomes from land-based sources, with>60% resulting from poor waste management. Marsh wrack deposits act asimportant accumulation zones for urban-derived AML, with high potential ecosystem impacts. Therefore, the innerestuary and its wrack deposits must be given priority for further research on AML transport, deposition, andcarbon-related effects, and mitigation actions.
Modelling the Distribution of Key Mediterranean Gorgonians: An Ensemble Approach to Unravel Broad-Scale Patterns and Guide Conservation Efforts
(John Wiley & Sons, 2024-11-22) Amblàs i Novellas, David; Matos, Fábio L.; Linares Prats, Cristina; Figuerola-Ferrando, Laura; Zentner, Yanis; Garrabou, Joaquim
Aim Determining the species distribution and factors shaping it is a major challenge for conservation planning. Ecological niche models (ENMs) facilitate the comprehension of how environmental factors may influence species occurrence, providing spatially explicit information relevant to conservation. Therefore, our aim was to estimate the potential distribution of key habitat-forming Mediterranean gorgonians, whose conservation would protect many co-occurring species. Location Mediterranean Sea. Methods We modelled the potential distribution of the Mediterranean gorgonians Eunicella singularis, Eunicella cavolini, Paramuricea clavata and Corallium rubrum, using an ensemble ENM that combines nine algorithms. An extensive dataset of presence records (> 4378) collected through scientific surveys and citizen-science was intersected with oceanographic and topographic information within the coralligenous habitat depth range (< 150 m). This approach was used to map the habitat suitability of the study area for each species, assess related uncertainty, identify the most important factors shaping their distribution, and evaluate the overlap with the current network of Marine Protected Areas. Results The model identified higher habitat suitability for the occurrence of each gorgonian species in the NW Mediterranean, with roughness and temperature as the main drivers of their distribution. Conversely, the poorly sampled SE Mediterranean showed low habitat suitability, although there is a greater uncertainty associated with this estimate. The combined potential distribution of the four species is estimated to cover a quarter of Mediterranean shallow and mesophotic waters, but only 19% was included within protected areas. Main Conclusions The habitat suitability and uncertainty maps provide a valuable tool for the conservation and management of Mediterranean gorgonian species by offering spatially explicit information critical for marine spatial planning. The model estimates of habitat suitability showed low uncertainty for most of the study area, with few exceptions in the SE Mediterranean. Further studies, particularly in the SE Mediterranean will contribute to validate these results and will provide new information to improve future modelling efforts.
Cenozoic Ampelopsis and Nekemias leaves (Vitaceae, Ampelopsideae) from Eurasia: Paleobiogeographic and paleoclimatic implications
(Wiley, 2024-08-09) Tosal Alcobé, Aixa; Vicente Rodriguez, Alba; Denk, Thomas
We describe a new species of Ampelopsideae (Vitaceae), Nekemias mucronata sp. nov., from the Rupelian of Cervera (Spain) and revise another fossil species, Ampelopsis hibschii, originally described from Germany. Comparison with extant Ampelopsideae suggests that the North American species Nekemias arborea is most similar to Nekemias mucronata while the East Mediterranean Ampelopsis orientalis is the closest living relative of A. hibschii. Our review of fossil data indicates that, during the Eocene, four species of Ampelopsideae occurred in Eurasia, that is, N. mucronata in the Czech Republic, A. hibschii in Kazakhstan, and two fossil species in the Far East Ampelopsis cercidifolia and Ampelopsis protoheterophylla). In the Oligocene, a new species, Ampelopsis schischkinii, appeared in Kazakhstan; meanwhile, N. mucronata spread eastwards and southwards, and A. hibschii mainly grew in Central Europe. In the late Oligocene, N. mucronata became a relict in the Iberian Peninsula and Nekemias might have persisted in Western Eurasia until the latest Miocene (“Ampelopsis” abkhasica). The last occurrence of A. hibschii was in the Middle Miocene in Bulgaria, probably a refuge of humid temperate taxa, along with Ampelopsis aff. cordata. Carpological remains suggest that this lineage persisted in Europe at least until the Pleistocene. Our data confirm previous notions of the North Atlantic and Bering land bridges being important dispersal routes for Ampelopsideae. However, such dispersion probably occurred during the Paleogene rather than the Neogene, as previously suggested. A single species of Ampelopsideae, A. orientalis, has survived in Western Eurasia, which appears to have been linked to a biome shift.
Influence of inherited rifted margin architecture on continental collision dynamics
(Wiley, 2026-04-29) Ruh, J.B.; Granado, Pablo
Continental collision is a key process in lithospheric evolution, driving mountain building, crustalthickening, and supercontinent assembly. Within the Wilson cycle, collision marks the finalstage following rifting, ocean spreading, and subduction. Early rifting and rifted margindevelopment precede basement accretion and hard continental collision, leaving complexrecords that complicate tectonic interpretations. We present mantle-scale numerical modelssimulating rifting, post-rift thermal re-equilibration, convergence, subduction, and collision.Results show that a strong continental crust produces narrow rifted margins, while weak crustleads to margins with wider hyperextended domains. Subduction initiates beneath riftedcontinental margins due to inherited zones of reduced grain size. We assess the impact of syn-rift sediment rheology, erosion rates, and mantle serpentinization on non-magmatic riftedmargin evolution, subduction and collision. Our findings indicate that rift-inherited architectureprimarily controls basement accretion and collision style, more than surface processes orsediment rheology. Lithospheric shear zones with reduced grain size may serve as the locationof subduction initiation. Comparisons with natural examples such as the Alps, Pyrenees, andGreater Caucasus support a first-order interpretation of their structural and mechanicalevolution based on our models.
Reconstructing the Holocene volcanic past of El Hierro, Canary Islands
(Elsevier B.V., 2025-08) Prieto-Torrell, Claudia; Fernandez-Turiel, Jose-Luis; Rodriguez-Gonzalez, Alejandro; Aulinas Juncà, Meritxell; Beamud Amorós, Elisabet; Cabrera, M.C.; Criado, C.; Guillou, H.; Vidal-Matutano, P.; Perez-Torrado, Francisco Jose
We present a geochronologic study with unprecedented detail from 42 Holocene subaerial volcanic edifices of El Hierro Island, Canary Islands. The study of new and published K-Ar, 40Ar/39Ar, 14C, and paleomagnetic ages, constrained by stratigraphic, geomorphic, and anthracological criteria, significantly improves the geochronologic framework of the Holocene volcanism at El Hierro. Our combined experiments show that radiocarbon and paleomagnetic dating were the best methods to determine this young volcanism’s age. Indeed, small amounts of 40Ar* detected in most dated samples do not allow for calculating geologically significant ages. The preliminary anthracological study of charcoals is recommended before 14C dating. Thirty-six eruptive events (86 % of the total) were retained for the geochronological model developed with ChronoModel combining radiocarbon and paleomagnetic and using the Bayesian inference. Seventeen eruptions were dated for the first time. The Holocene eruptive activity at El Hierro exhibits significant variability over time, with recurrence intervals ranging from 34 to 1078 years. The most recent subaerial eruptions were Lomo Negro, 1412 [1560, 1242] cal BP (MAP, mode of the posterior distribution, and 95 % highest posterior density (HPD) interval) and Montaña del Tesoro, 1059 [1206, 967] cal BP. In addition, historical records suggest possible submarine eruptions in 1721, 1777, and 1793, as well as the more recent and well-documented Tagoro volcano submarine eruption (2011–2012 CE). This recent low recurrence subaerial volcanic activity is unusual for an oceanic volcanic island in the juvenile shield growth stage. The volcanic edifices resulted from hybrid Strombolian monogenetic eruptions with alternating or simultaneous emission of pyroclastic tephra and lava flows. The absence of lava flows in the eruptions of the highest part of the island’s summit is worth noting. This volcanic activity focused on the three rifts that configure the tetrahedral shape of the island, although the NW rift concentrated 50 % of the eruptions. These results contextualize the volcanic hazard of El Hierro in the face of eventual future eruptions.
Impact of volcanic emissions on the air quality during the 2021 volcanic eruption of Tajogaite, La Palma: Implications for population exposure to volcanic pollutants
(Elsevier B.V., 2026-03-01) Moune, Séverine; Navarrete, Wilman; Nedelec, Jean Marie; Rodriguez-Gonzalez, Alejandro; Tomašek, Ines; Vilches, Jon; Perez-Torrado, Francisco Jose; Eychenne, Julia; Paris, Raphael; Borbon, Agnès; Jessop, David; Gouhier, Mathieu; Gisbert Pinto, Guillem; Calafat Frau, Antoni; Colomb, Aurélie; Fernández Turiel, José Luis; Gaussen, Vincent; Gorce, Clara
Volcanic eruptions inject particles (tephra) and gases into the atmosphere, impacting air quality. To provide new insights into this process, we focus on the 3-month-long 2021 Tajogaite eruption, on La Palma in the Canary Islands, Spain. This eruption emplaced lava flows and produced tephra and gases in multiple sustained plumes. We examined the relationship between air quality, tephra dispersion and deposition, and eruption dynamics. We reconstructed the spatiotemporal variations in tephra deposition using a collection network deployed around the island and maintained throughout the eruption, while plume dispersion was tracked using satellite observations. These datasets were compared to the air quality monitoring data from the local regulatory network using time-series analyses. Our findings reveal distinct peaks in tephra deposition rates (a few g/m2/h 20 km away from the vent, up to more than 2000 g/m2/h at locations less than 3 km from the vent), related to both increased explosive activity at the volcanic vents and specific atmospheric conditions. We show that the fluctuations of tephra emission were the main driver of the particulate matter (PM) concentration variations, outweighing contributions from secondary aerosol formation through volcanic SO2 conversion. We evidence spatial disparity in the impact on air quality, with the western half of La Palma island experiencing higher amplitude and more frequent pollution peaks than the eastern half. We demonstrate that even low-explosivity basaltic eruptions can significantly affect air quality by generating and dispersing fine PM and gases over wide areas. Moreover, elevated PM concentrations persist beyond the duration of intense tephra deposition episodes, thereby extending the period of population exposure. These results have important implications for understanding and mitigating human exposure to volcanic pollutants.
Paleoenvironmental constraints influencing charophyte communities in an Early Cretaceous Karstic Lake, La Pedrera de Meià Konservat-Lagerstätte (Southern Pyrenees): combining geochemical and palaeoecological analyses.
(Springer Verlag, 2025-01-08) Pérez Cano, Jordi; Gil Delgado, Alejandro; Oms, Oriol; Mercedes Martín, Ramon
The combined sedimentological and palaeoecological analysis of charophyte-rich carbonate microfacies is proven to be a useful methodology for the palaeoenvironmental reconstruction of continental settings. However, the integration of these charophyte assemblages with geochemical proxies has not been explored, yet. In the present work, the charophyte-rich muddy carbonates of the Barremian La Pedrera de Meià Konservat-Lagerstätte (Southern Pyrenees, Spain) were studied from a taxonomic, taphonomic, and palaeoecological viewpoint, and the results were later integrated with previously published paleoenvironmental proxies (δ13C, δ18O, and elemental geochemistry). In the studied locality, monospecific Echinochara sp.–Charaxis spicatus meadows are only found in the temporary lakes recorded in the lower stages of lake infilling. The high Al, K, Fe and Ti concentrations and δ18O values previously described in these carbonates indicate meteoric infilling followed by evaporation periods. Freshwater and brackish communities are found in the upper stage of lake infilling. Freshwater settings had mixed meadows with Atopochara–Clavatoraxis, Clavatoroidae utricles–Clavatoraxis, and Ascidiella–Favargerella plants, while the brackish environments, that occurred laterally to freshwater, contain meadows dominated by porocharacean– Charaxis sp., and Echinochara sp.–Charaxis spicatus plants. Miliolids and broken dasycladaceans also occur in these facies. Sr/Ba ratios, REE + Y concentrations, and δ18O values previously reported in these lacustrine carbonates indicate prevalence of freshwater environments with occasional marine influence, which agrees with the occurrence of distinct brackish and freshwater charophyte assemblage and marine-affinity organisms, suggesting that during the last stage of lake evolution, the system was part of a coastal wetland. This work demonstrates that the integration of geochemical, palaeontological and palaeoecological datasets improves the understanding of the fossil continental carbonate settings and their evolution.
From scientific research to digital reconstruction: integration of historical documentation and VR experiences in Gerri de la Sal Project
(Universitat Politècnica de València, 2026-01-12) Dinarès Cabrerizo, Oriol; Carola i Molas, Eloi; Costa Badia, Xavier; Vallès, Jan; Yagüe Medina, Aroa; Mir Pellicer, Xavier; Puras, Guillem; Ferrer García, J. Oriol (José Oriol); Gratacós Torrà, Òscar; Rivas, Gonzalo; Sellés, Albert; Muñoz, J. A.; Santolaria, Pablo; Matteis, Marco de; Muñoz, Josep Anton
There is a lack of bibliography concerning the specific methodology and limitations of historical data gathering to achieve high-quality and accurate productions of virtual reality (VR) and augmented reality (AR) technology applied to heritage dissemination. Most papers focus on the technical features and dissemination application of 3D and VR; the rigour of the research process specifically aimed at 3D reconstruction is usually not addressed, or taken into account by digitalization technicians. Although digitalization of heritage sites carried out by the same team or project in charge of its documentation mitigates the problem, several digitalization and public dissemination projects are conceived as a subsequent step, usually conducted by specialists or technicians not necessarily familiar with the heritage site’s features. This paper addresses this methodological need through the researcher’s experience in a multidisciplinary VR heritage project. The aim is to integrate historical research within the development of a VR museum within the Orígens UNESCO Global Geopark in the Catalan Pyrenees, Spain. Specifically, it explores the particular needs, challenges, and limitations of historical data gathering to accurately produce VR reconstructions of a cultural heritage site in Gerri de la Sal. The site involves studying a prehistoric salt production complex, a medieval monastery, and traditional salt-making processes. The experience has allowed the authors to propose a viable 3-step work plan to conduct research and documentation for VR dissemination. The result is a 7-minutes long VR documentary, to be displayed at the local museum of Gerri de la Sal, meeting the international VR reconstructions rigour guidelines. Thanks to successfully achieving this objective, the researchers have also addressed basic limitations of the proposed methodology and have proposed viable strategies to overcome them.
Where the salt sheet ends - submarine allochthonous salt advance and hindrance, The Elda Salt Sheet, Eastern Prebetics (Southern Iberia)
(Elsevier B.V., 2025-12-01) Canova, David P.; Cofrade Rivas, Gabriel; Roca i Abella, Eduard; Matteis, Marco de; Ferrer García, J. Oriol (José Oriol)
The Eastern Prebetics are part of the External Zone of the Betic Fold-and-Thrust Belt in SE Iberia where a significant amount of salt structures crops out including: diapirs, allochthonous sheets, welds, primary and secondary minibasins, and rafts. Our study focuses on the subsalt, syn-contractional, early to middle Miocene (Aquitanian-Langhian) stratigraphy of the Elda Salt Sheet, aiming to document the sub seismic scale deformation and salt-sediment interactions during allochthonous salt advance. Stratigraphic sections, halokinetic fold analysis, geologic field mapping and foraminiferal dating are used to characterize the subsalt sediments exposed in contact with the northwestern edge of the outcropping Elda Salt Sheet. Based on the subsalt sedimentary and structural relationships we show that the Elda Salt Sheet advanced at least 8 km towards the north during the syn-orogenic Aquitanian – Langhian times before being buried during the latest Langhian - Serravallian times. This overall northward advance can be defined by six main phases. All the phases occur in submarine conditions in a carbonate ramp with water depths ranging from 10's to 100's of meters and are: (1) the extrusion of a salt sheet in an inner – outer carbonate ramp environment coeval to the onset of regional Oligocene-Miocene shortening corroborated by an Aquitanian aged flat and stranded intrasalt stringers along the subsalt flat; (2) Burdigalian-early Langhian burial of the salt sheet toe in an outer shelf – basinal environment where pinned inflation, and subsequent breakout of a confined salt sheet is evidenced by a hectometric halokinetic fold ramp and rafts of Burdigalian stratigraphy above the salt sheet. (3) early-middle Langhian rapid lateral advance of the salt sheet along a base salt flat which occurred in a deepwater basinal environment; (4) middle-late Langhian hindrance of the salt advance, development of subsalt decametric thick and decametric spaced halokinetic fold ramps in a basinal – outer shelf environment; (5) late Langhian salt sheet burial by shallow water carbonates and deepwater basinal marlstones; and (6) subsidence of secondary minibasins. These stages reflect a detailed history of a salt sheet lineage. This field-based study documents for the first time the structural and stratigraphic architecture of a subaqueous salt sheet lineage in a contractional setting.
3D modeling of gas hydrates distribution in South Hydrate Ridge (Cascadia accretionary prism, offshore Oregon) through geological time
(Sociedad Geológica de España, 2024) Cabello López, Patricia; Marin, Mar; Cassola, T.; Falivene Aldea, Oriol; Gil-Ortiz, Marc; Yeste, Luis Miguel; Agustí García-Navarro, Àlvar; Uranga Moran, Rodolfo Martín; Berndt, C.
South Hydrate Ridge (SHR) is an anticlinal structure that is part of the Cascadia accretionary prism, located offshore of Oregon. SHR has been the subject of multiple multidisciplinary studies and oceanographic campaigns focused on understanding the functioning of gas hydrate systems. Herein, we present a 3D dynamic model of SHR that simulates the distribution of gas hydrates over geological time. This model is based on the application on petroleum system modeling tools and builds upon previously published data and results from 2D models already published. The model reproduces the complex structure of SHR and distinguishes a total of 7 stratigraphic units (from the Pliocene to the Present), primarily composed of silty clays and clays interbedded with sands. The model predicts a heterogeneous distribution of gas hydrate saturation in SHR at present, with higher values observed on the flanks of the main ridge and on the crests of secondary highs (maximum values of up to 23% of porosity). According to the model, the initiation of hydrate formation occurred mainly between 1.7 Ma and 1.6 Ma, and its accumulation has persisted throughout the evolution of the ridge, alternating with dissociation in certain areas and moments. Such variable distribution and the alternation of formation and dissociation would respond to the differential growth of the structures forming the SHR. These structures control the availability of gas, which migrates upward through deformed strata, and would influence the distribution of the gas hydrate stability zone.

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