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This study integrates geophysical-geochemical data to investigate the thermochemical structure of the lithosphere and sublithospheric mantle, along the Southern Tyrrhenian Basin, Apennines, Adriatic Sea, Dinarides, and Carpathians-Balkanides. We present the lithospheric structure of the Adria microplate and the two opposing mantle slabs along its NE and SW margins. The modelling shows the presence of two asthenospheric mantle wedges aligning with the Apenninic and Dinaric continental mantle slab rollback, along with cold (-200ºC) sublithospheric anomalies beneath Adria’s NE and SW margins. In the northern Adria region, the lithosphere undergoes synchronous thinning in the Tyrrhenian domain and thickening toward the forefront of the northern Apennines. This is associated with the northeastward rollback of the SW Adriatic slab, leading to subsequent delamination of the continental mantle. In the southern Adria region, the complex deep structure results from the variably oriented lithospheric slabs, and nearly 90-degree shift of the tectonic grain between the southern Apennines and the Calabrian Arc. At the SW Adria margin, beneath the northern Apennines, the thermal sublithospheric anomaly is attached to the shallower lithosphere, while a slab gap is modelled in the southern Apennines. One possibility is that the gap is due to a recent horizontal slab tear. Along the NE margin of Adria, the thermal anomaly penetrates to depths of about 200 km in the northern Dinarides and 280 km in the southern Dinarides, shallower than the SW Adria anomaly, which extends to at least 400 km depth.

This study integrates geophysical-geochemical data to investigate the thermochemical structure of the lithosphere and sublithospheric mantle, along the Southern Tyrrhenian Basin, Apennines, Adriatic Sea, Dinarides, and Carpathians-Balkanides. We present the lithospheric structure of the Adria microplate and the two opposing mantle slabs along its NE and SW margins. The modeling shows the presence of two asthenospheric mantle wedges aligning with the Apenninic and Dinaric continental mantle slab rollback, along with cold (−200°C) sublithospheric anomalies beneath Adria's NE and SW margins. In the northern Adria region, the lithosphere undergoes synchronous thinning in the Tyrrhenian domain and thickening toward the forefront of the northern Apennines. This is associated with the northeastward rollback of the SW Adriatic slab, leading to subsequent delamination of the continental mantle. In the southern Adria region, the complex deep structure results from the variably oriented lithospheric slabs, and nearly 90-degree shift of the tectonic grain between the southern Apennines and the Calabrian Arc. At the SW Adria margin, beneath the northern Apennines, the thermal sublithospheric anomaly is attached to the shallower lithosphere, while a slab gap is modeled in the southern Apennines. One possibility is that the gap is due to a recent horizontal slab tear. Along the NE margin of Adria, the thermal anomaly penetrates to depths of about 200 km in the northern Dinarides and 280 km in the southern Dinarides, shallower than the SW Adria anomaly, which extends to at least 400 km depth.

Stratigraphic and geochemical evidence suggests that the Mediterranean Sea underwent widespread salinization and a kilometer-scale evaporative drawdown between 5.97 to 5.33 million years ago, during the period known as the Messinian salinity crisis (MSC). The mechanisms responsible for the accumulation of one million cubic kilometers of salt on the sea floor and the impact on terrestrial and marine fauna and on climate are being better understood in the last decades. However, the presence of relatively fresh water sediment containing fossil fauna of eastern (Paratethyan) provenance in the last stages of the MSC poses severe problems to understand the ending of the crisis. These brackish-water deposits, known as the Lago-Mare unit, are sometimes found at elevations close to the present sea level, in apparent contradiction with the coetaneous evaporitic sediment found in deeper, central parts of the Mediterranean. We make use of landscape evolution models calibrated with sediment transport and river incision data to explore plausible scenarios of climate and sea level changes during the MSC. The results show that, upon full isolation, the large initial evaporative sea level fall of the Mediterranean leads to a progressive capture of the waters from nearby lacustrine basins such as the Black Sea or the Pannonian Basin. This drainage area expansion triggers a gradual sea level rise in the Mediterranean. Milankovic climate oscillations superimposed to this trend lead to large-amplitude (500-1000 m) harmonic sea level variations reaching ever-higher levels. This is consistent with the salt precipitation in deeper areas during lowstands and Lago-Mare deposition during highstands in marginal areas. This model may also explain the seemingly contradiction between the high-level Lago-Mare deposits and the km-scale sea level drop estimated from erosion markers and implicit in the Zanclean cataclysmic reflooding model.

The deformation of the upper mantle is predominantly governed by the mechanical behavior of olivine (Karato et al., 1989). During mantle flow, olivine undergoes crystal-plastic deformation, leading to the development of crystallographic preferred orientations (CPOs). In this process, the a-axes of olivine polycrystalline aggregates align with the flow direction (Hansen et al., 2012). Consequently, the observed CPOs in olivine-rich rocks serves as an indicator of the mantle flow direction. While the influence of plastic deformation is well understood, the role of dynamic recrystallization during deformation remains not fully comprehended, hindering our ability to interpret the deformation history of naturally-deformed rocks. This contribution employs microdynamic numerical simulations of olivine polycrystalline aggregates with varying iron content (fayalite content) to explore the CPO and grain size response to dynamic recrystallization. Utilizing a full-field approach with explicit simulation of viscoplastic deformation (http://www.elle.ws; Bons et al., 2008; Piazolo et al., 2019) and dynamic recrystallization processes under simple shear boundary conditions up to high strain, this study indicates that simulations with only dislocation glide and also those including recrystallization successfully reproduce such steady state conditions, without requiring other potential mechanisms. The model establishes a framework for understanding the development of olivine CPOs in mantle rocks, highlighting the interplay between plastic deformation and dynamic recrystallization processes, including grain boundary migration, intracrystalline recovery, and new grain nucleation.

Peridotites, which primarily consist of olivine, are rocks located in the Earth's upper mantle. The mechanical behavior of the upper mantle is heavily influenced by this mineral. When the mantle undergoes flow, olivine experiences viscoplastic deformation, resulting in the development of crystallographic preferred orientations (CPO). Scientists can analyze the observed CPO in olivine-rich rocks to determine the direction of mantle flow. In this study, microdynamic numerical simulations are conducted on aggregates of olivine to investigate the effects of dynamic recrystallization during viscoplastic deformation on the microstructure and CPO. This dataset contains the output files of the simulations PT248, PT263 and PT345, using the viscoplastic fast Fourier transform (VPFFT, Lebensohn and Rollet, 2020) in conjunction with the ELLE modeling platform (Bons et al., 2008). For the visualization of the microstructures the information included in these output files can be launched using the software toolbox MTEX (Bachmann et al., 2011).

Creep due to ice flow is generally thought to be the main cause for the formation of crystallographic preferred orientations (CPOs) in polycrystalline anisotropic ice. However, linking the development of CPOs to the ice flow history requires a proper understanding of the ice aggregate's microstructural response to flow transitions. In this contribution the influence of ice deformation history on the CPO development is investigated by means of full-field numerical simulations at the microscale. We simulate the CPO evolution of polycrystalline ice under combinations of two consecutive deformation events up to high strain, using the code VPFFT (visco-plastic fast Fourier transform algorithm) within ELLE. A volume of ice is first deformed under coaxial boundary conditions, which results in a CPO. The sample is then subjected to different boundary conditions (coaxial or non-coaxial) in order to observe how the deformation regime switch impacts the CPO. The model results indicate that the second flow event tends to destroy the first, inherited fabric with a range of transitional fabrics. However, the transition is slow when crystallographic axes are critically oriented with respect to the second imposed regime. Therefore, interpretations of past deformation events from observed CPOs must be carried out with caution, particularly in areas with complex deformation histories.

This data set contains the output files with the crystal orientation of each simulation presented in the article Can changes in deformation regimes be inferred from crystallographic preferred orientations in polar ice? https://doi.org/10.5194/tc-16-2009-2022 in this repository http://hdl.handle.net/10261/270644 (run using the open-source software platform ELLE; Bons et al., 2008). For the visualization of the crystallographic preferred orientation the information contained in these output files can be loaded to the software toolbox MTEX (Bachmann, F., Hielscher, R. and Schaeben, H. Grain detection from 2d and 3d EBSD data—Specification of the MTEX algorithm. Ultramicroscopy, 111(12), pp.1720-1733. 2011).

The Balearic Promontory (Spain) is of key importance to understand the tectonic kinematics of the westernmost Mediterranean, because its continued marine sedimentation has recorded the contrasting effects expected from competing geodynamic models proposed for the region. Near the center of this promontory, between the islands of Mallorca and Ibiza, the Miocene to Pleistocene stratigraphy of the Central Mallorca Depression presents an ideal record of the tectonic deformation that has received only limited attention. We use a widespread dataset of 2D seismic reflection profiles to identify, interpret and map the main prominent reflectors and extrapolate the thickness of the pre-Messinian and Pliocene-Quaternary sedimentary units. We then quantify the timing and style of deformation related to the various fault systems. Our results reveal for the first time a series of aligned small depressions bounded by extensional and strike-slip faults and filled with Plio-Quaternary sediment, perfectly aligned with the sub-basins of the onshore Mallorca Graben. A subsidence analysis confirms this correlation. We identify non-cylindrical deformation within the Plio-Quaternary unit that is remarkably similar to that observed onshore, suggesting continuous fault zones from the Central Mallorca Depression to Mallorca Island. We interpret an intra-PQ unconformity as the marker of a transition from extensional to strike-slip tectonic regime. The strike-slip stage is represented by both transpressional and transtensional structures, interpreted as restraining/releasing bends respectively and step overs along the faults. We show that these offshore faults in the Central Mallorca Depression overlap well with seismic epicenters and suggest major active strike-slip corridors that have an onshore continuity both until eastern Mallorca and in the southwestern Ibiza margin. The role of previous tectonic inherited structures (rifting, Betic thrusts, post-orogenic collapse) on the deformation rep

During the Messinian Salinity Crisis (MSC, 5.97–5.33 Ma), thick evaporites were deposited in the Mediterranean Sea associated with major margin erosion. This has been interpreted by most authors as resulting from water level drop by evaporation but its timing, amplitude and variations between subbasins are poorly constrained due to uncertainty in post-Messinian vertical motions and lack of a clear time-correlation between the marginal basin and offshore records. The Balearic Promontory and surrounding basins exemplify a range of responses to this event, from margin erosion to up to a kilometre thick Messinian units in the abyssal areas containing the majority of the MSC halite. The Balearic Promontory contains unique patches of halite with thickness up to 325 m at intermediate depths that provide valuable information on water level during the stage of halite deposition. We compile seismic markers potentially indicating ancient shorelines during the drawdown phase: the first is marked by the transition from the MES to UU based on seismic data. The second is the limit between the bottom erosion surface (BES) and abyssal halite deposits. We restore these shorelines to their original depth accounting for flexural isostasy and sediment compaction. The best-fitting scenario involves a water level drop of ca. 1,100 ± 100 m for the Upper unit level and 1,500 ± 100 m for the BES level. According to our results, halite deposition began in the Central Mallorca Depression at 1,300–1,500 m depth, perched hundreds of metres above the deep basins, which were at 1,500–1,800 m (Valencia Basin) and >2,900 m (Algerian Basin). The hypothesis that erosion surfaces were formed subaerially during the drawdown phase is consistent with a model of halite deposition before/during the water level drop of at least 1,000 m, followed by the deposition of the Upper unit until the MSC is terminated by the reinstatement of normal marine conditions.

[Background] There is a considerable need to incorporate biomarkers of resistance to new antiandrogen agents in the management of castration-resistant prostate cancer (CRPC)., [Methods] We conducted a phase II trial of enzalutamide in first-line chemo-naïve asymptomatic or minimally symptomatic mCRPC and analyzed the prognostic value of TMPRSS2-ERG and other biomarkers, including circulating tumor cells (CTCs), androgen receptor splice variant (AR-V7) in CTCs and plasma Androgen Receptor copy number gain (AR-gain). These biomarkers were correlated with treatment response and survival outcomes and developed a clinical–molecular prognostic model using penalized cox-proportional hazard model. This model was validated in an independent cohort., [Results] Ninety-eight patients were included. TMPRSS2-ERG fusion gene was detected in 32 patients with no differences observed in efficacy outcomes. CTC detection was associated with worse outcome and AR-V7 in CTCs was associated with increased rate of progression as best response. Plasma AR gain was strongly associated with an adverse outcome, with worse median prostate specific antigen (PSA)-PFS (4.2 vs. 14.7 m; p < 0.0001), rad-PFS (4.5 vs. 27.6 m; p < 0.0001), and OS (12.7 vs. 38.1 m; p < 0.0001). The clinical prognostic model developed in PREVAIL was validated (C-Index 0.70) and the addition of plasma AR (C-Index 0.79; p < 0.001) increased its prognostic ability. We generated a parsimonious model including alkaline phosphatase (ALP); PSA and AR gain (C-index 0.78) that was validated in an independent cohort., [Conclusions] TMPRSS2-ERG detection did not correlate with differential activity of enzalutamide in first-line mCRPC. However, we observed that CTCs and plasma AR gain were the most relevant biomarkers.

Within the complex geodynamic context of the Central Mediterranean, the Adria Plate has played a major role in accommodating convergence between the Africa and Eurasia Plates. Understanding the tectonic deformation history of Adria Plate, which involves the development of the opposing Apennines and Dinarides-Hellenides thin- and thick-skinned fold belts, remains a great challenge. Despite numerous geological and geophysical reconstructions of the Adria Plate, the quantified pre-compressional width and crustal structure are still a matter of debate. To address these uncertainties, we built a regional geological cross-section along a SW-NE transect through the Southern Apennines and Southern Dinarides by integrating published structural cross-sec- tions. Applying the line length method for the cover units and assuming constant area for the basement, we have reconstructed the pre-compressional width of the Adria Plate and its crustal thickness during the Middle-Late Jurassic. The unfolding of the sedimentary cover along the SW- NE cross-section results in an undeformed length, width of Adria, of ~1100 km during Middle- Late Jurassic yielding ~340 km of minimum shortening; ~180 km for the Southern Apennines24 and ~160 km for the Southern Dinarides. We have reconstructed the crustal basement thickness for three different domains along the cross-section: Apenninic Platform-Lagonegro, Apulian Platform-Budva, and High Karst-Jadar Kopaonik, yielding respectively 6, 24 and 22 km. The estimated width of the Adria Plate is smaller than the previously suggested range of 1175 to 167028 km. Nevertheless, our results are consistent with a paleogeographic scenario in which Adria would be partly similar to the Bahamas during the Jurassic where the carbonate factory plays a decisive role. Such scenario is characterized by abrupt platform-basin transitions occurring in narrow zones defined by the Jurassic rifting. Our reconstructed crustal thicknesses are consistent with typical contin

The Central Mallorca Depression (CMD) located in the Balearic Promontory (Western Mediterranean) contains a well-preserved evaporitic sequence belonging to the Messinian Salinity Crisis (MSC) salt giant, densely covered by high- and low-resolution seismic reflection data. It has been proposed recently that the MSC evaporitic sequence in the CMD could be a non-deformed analogue of the key MSC area represented by the Caltanissetta Basin in Sicily. This presumed similarity makes the CMD an interesting system to better understand the MSC events. Physics-based box models of the water mixing between sub-basins, built on conservation of mass of water and salt, help constrain the hydrological conditions under which evaporites formed during the MSC. Those models have been widely used in the literature of the MSC in the past two decades. They have been mostly applied to the Mediterranean Sea as a whole focusing on the Mediterranean–Atlantic connection, or focusing on the influence of the Sicily Sill connecting the Western and Eastern Mediterranean Sea. In this study, we apply a downscaled version of such modelling technique to the CMD. First, we quantify the present-day volumes of the MSC units. We then use a reconstructed pre-MSC paleo-bathymetry to model salinity changes as a function of flux exchanges between the CMD and the Mediterranean. We show that a persistent connection between the CMD and the Mediterranean brine near gypsum saturation can explain volume of Primary Lower Gypsum under a sea level similar to the present. For the halite, on the contrary, we show that the observed halite volume cannot be deposited from a connected CMD-Mediterranean scenario, suggesting a drawdown of at least 850 m (sill depth) is necessary. Comparison between the deep basin halite volume and that of the CMD shows that it is possible to obtain the observed halite volume in both basins from a disconnected Mediterranean basin undergoing drawdown, although determining the average salinity of

Lithospheric slab tearing, the process by which a subducted lithospheric plate is torn apart and sinks into the Earth’s mantle, has been proposed as a cause for surface vertical motions in excess of 100 s of meters. However, little is known about the mechanisms that help initiate and control the propagation of slab tearing and the associated uplift. This study aims to explore these processes by means of 3D thermo-mechanical geodynamic modelling of a slab retreat oblique to a continental margin, using the Gibraltar Arc region (Betic Cordillera) as a scenario for inspiration. Our results suggest that the obliquity of the continental passive margin relative to the subduction trench leads to an asymmetric distribution of subduction forces and strength, facilitating the initiation of slab tearing. The model results predict a lateral migration of the tearing point at a velocity ranging between 38 and 68 cm/yr for a sublithospheric-mantle viscosity of up to 1e+22 Pa s. This fast slab tearing propagation yields uplift rates of 0.23–2.16 mm/yr above the areas where the subducted slab is torn apart, depending on mantle viscosity. Although a more detailed parametric exploration is needed, this range of uplift rates is compatible with the uplift rates required to overcome seaway erosion along the Atlantic-Mediterranean marine corridors during the Late Miocene, as proposed for the onset of the Messinian Salinity Crisis.

During the Messinian Salinity Crisis (MSC), as the Mediterranean realm experienced partial desiccation, water levels in Paratethys, a vast waterbody in the middle of Eurasia, remained largely unaffected except in its easternmost domain, the Caspian basin, which experienced a severe partial desiccation. Still, its relation and role in the dynamics of the MSC are controversial.Here we reconstruct the paleogeographic evolution of the Paratethys region during the MSC. We show that the Paratethys realm irreversibly fragmented into smaller basins (Dacian, Black Sea, Caspian) triggering a reorganization of the Paratethys watershed during the MSC. The Paleo-Don River, the main river flowing in Paratethys, was captured by the Black Sea basin enhancing the excess of water was spilled in the Mediterranean and affecting the hydrology of the Mediterranean during the Lago Mare phase of the MSC. The Caspian basin, isolated and deprived of major river inflows, became partially desiccated, experiencing a ~400m base level drop. Extensive canyons developed and expanded in the central-northern Caspian Basin forming a new river - the Volga, that would later capture the eastern watershed of the Paleo-Don and partially refill the Caspian basin. These findings reveal that the MSC had extensive, continental consequences: destabilizing the Paratethys realm and reorganizing the river networks of Eastern Europe. This paleogeographic reorganization and the shifts in freshwater budgets may represent a key piece of the puzzle of the water balance in the Mediterranean basin during the MSC.

The extreme Mediterranean sea-level drop during the Messinian salinity crisis has been known for >50 years, but its amplitude and duration remain a challenge. Here we estimate its amplitude by restoring the topography of the Messinian Nile canyon and the vertical position of the Messinian coastline by unloading of post-Messinian sediment and accounting for flexural isostasy and compaction. We estimate the original depth of the geomorphological base level of the Nile River at ~600-m below present sea level, implying a drawdown 2-4 times smaller than previously estimated from the Nile canyon and suggesting that salt precipitated under 1-3-km deep waters. This conclusion is at odds with the nearly-desiccated basin model (>2 km drawdown) dominating the scientific literature for 50 years. Yet, a 600-m drawdown is ca. five times larger than eustatic fluctuations and its impact on the Mediterranean continental margins is incomparable to any glacial sea-level fall.

Physical connectivity between marine basins facilitates population exchange and hence controls biodiversity. The Mediterranean Sea is a semi-restricted basin with only a small two-way connection to the global ocean, and it is a region heavily impacted by climate change and biological invasions today. The massive migration of non-indigenous species into the basin through the Suez Canal, driven and enabled by climate warming, is drastically changing Mediterranean biodiversity. Understanding therefore the origin and cause(s) of pre-existing biodiversity patterns is crucial for predicting future impacts of climate change. Mediterranean biodiversity exhibits a west-to-east decreasing gradient in terms of species richness, but the processes that resulted in this gradient have only been hypothesized. By examining the fossil record, we provide evidence that this gradient developed 5.33 million years ago at the end of the Messinian Salinity Crisis, and it was therefore caused by the re-population of the basin by marine species with a dominating western source at the Mediterranean¿Atlantic gateway.

In this study we present a geophysical-geochemical integrated model of the thermochemical structure of the lithosphere and uppermost mantle of the Adria and Tisza microplates along two transects running from the Northern Apennines to the Pannonian Basin, and from the Southern Apennines to the Balkanides, respectively. The objectives are to image crustal thickness variations and characterize the different mantle domains. In addition, we evaluate the topographic response of opposed subductions and discuss their implications in the evolution of the region. Results show a more complex structure and slightly higher average crustal density of Adria compared to Tisza microplate. Below the Tyrrhenian Sea and Western Apennines, Moho is much shallower (< 25 km) than along the Eastern Apennines, where it can reach depths of 50-55 km. The LAB depth shows significant lateral variations, from the shallow LAB of the Tyrrhenian Sea and Western Apennines (< 80 km) to the thick LAB underneath the eastern Apennines and Adriatic Sea (150 and 125 km, respectively). Our results are consistent with the presence of two mantle wedges, resulting from the rollback of the Ligurian-Tethys and Vardar-NeoTethys oceanic slabs followed by continental mantle delamination of the eastern and western distal margins of Adria. These two opposed slabs beneath the Apennines and Dinarides are modelled as two thermal sublithospheric anomalies of -200°C. A Tecton garnet lherzolite (Tc_2 of Griffin et al., 2009) for the whole lithospheric mantle allows fitting geoid height and long-wavelength Bouguer anomalies. Most of the elevation along the profile is under thermal isostasy and departures can be explained by regional isostasy with an elastic thickness between 10 and 20 km. This research has been funded by the GeoCAM Project (PGC2018-095154-B-I00) with the contribution of the China Scholarship Council.

The late Miocene evolution of the Mediterranean Basin is characterized by major changes in connectivity, climate and tectonic activity resulting in unprecedented environmental and ecological disruptions. During the Messinian Salinity Crisis (MSC, 5.97-5.33 Ma) this culminated in most scenarios first in the precipitation of gypsum around the Mediterranean margins (Stage 1, 5.97-5.60 Ma) and subsequently > 2 km of halite on the basin floor, which formed the so-called Mediterranean Salt Giant (Stage 2, 5.60-5.55 Ma). The final MSC Stage 3, however, was characterized by a "low-salinity crisis", when a second calcium-sulfate unit (Upper Gypsum; substage 3.1, 5.55-5.42 Ma) showing (bio)geochemical evidence of substantial brine dilution and brackish biota-bearing terrigenous sediments (substage 3.2 or Lago-Mare phase, 5.42-5.33 Ma) deposited in a Mediterranean that received relatively large amounts of riverine and Paratethys-derived low-salinity waters. The transition from hypersaline evaporitic (halite) to brackish facies implies a major change in the Mediterranean’s hydrological regime. However, even after nearly 50 years of research, causes and modalities are poorly understood and the original scientific debate between a largely isolated and (partly) desiccated Mediterranean or a fully connected and filled basin is still vibrant. Here we present a comprehensive overview that brings together (chrono)stratigraphic, sedimentological, paleontological, geochemical and seismic data from all over the Mediterranean. We summarize the paleoenvironmental, paleohydrological and paleoconnectivity scenarios that arose from this cross-disciplinary dataset and we discuss arguments in favour of and against each scenario.

Deception Island (South Shetland Islands) is one of the most active volcanoes in Antarctica, with more than 20 explosive eruptive events registered over the past centuries. Recent eruptions (1967, 1969, and 1970) and volcanic unrest episodes (1992, 1999, and 2014–2015) demonstrate that volcanic activity is likely occurring in the future. This is of special concern for scientists, logistic personnel, and tourists, since the South Shetland Islands are an important tourist destination and host numerous year-round and seasonal scientific stations and base camps. Significant efforts have been made to understand the complex magmatic and volcanic evolution of Deception Island with special interest on its subaerial part. However, studies on submerged volcanic cones within Port Foster, the sea-flooded part of Deception Island's caldera depression, are comparatively scarce. Here, we provide a full characterization of Stanley Patch volcano, the largest of these volcanic edifices. Estimated morphometric parameters based on new multibeam bathymetric data, supported by petrographic and chemical observations from rock samples collected on the crater rim, reveal that Stanley Patch volcano grew in a subaerial environment. This result, combined with previous findings and new sedimentological evidence from our ultra-high resolution seismic profiles, allow to further detail the island's geologic evolution since the caldera collapse. We conclude that the complete flooding of Port Foster could have only occurred after the formation of Stanley Patch volcano, i.e. during the last ~2000 years, and in a time period of a few days or less.

Following the termination of the Messinian salinity crisis ~5.3 million years ago, massive sedimentation in the Eastern Mediterranean Sea formed the huge Nile Delta. Alongside delta propagation, a continental shelf was accreted along the Levant margin. For several decades it was assumed that these two sedimentary structures were closely connected. Levant shelf deposits are composed of Nile-derived sediments and present-day measurements show that sand is currently being transported alongshore from the Nile Delta to offshore Israel. This study reexamines the existing paradigm about sediment transport and shelf-delta connection. We show that longshore sand transport is just a small part of a much larger process termed here margin-parallel sediment transport (MPST). Sand is transported in a nearshore shallow-water belt where marine currents are highly energetic. At the same time, shale is transported at greater depths over the deeper shelf and the continental slope where marine currents are weaker. To model the accretion of the Levant shelf alongside the Nile Delta we use a 3D, diffusion-based, stratigraphic modeling tool (DionisosFlow) with a new module representing MPST. Our results show that margin-parallel transport of silt and clay in the deeper waters accounts for the bulk of deposition offshore Israel and is responsible for the development of the Levant shelf. Moreover, though MPST has begun coevally with delta formation, massive accretion of the Levant shelf was delayed by 2–3 My. Initially, a continental shelf formed offshore Sinai, then offshore Israel, and most recently along the Lebanon coast. Our model also demonstrates the significant lithological differences observed between sedimentation in front of the Nile River mouth and along adjacent continental margin. High energy down-slope sediment transport carries sand, silt, and clay, whereas margin-parallel currents are relatively weak and carry mainly silt and clay. One exception within the margin-parallel s

The opening of internally-drained (endorheic) sedimentary basins often leads to a major drainage change, re-excavation of the basin sedimentary infill, and transient landscape. The timing of such basin openings can be dated only in exceptional cases in which the youngest sedimentary infill remains preserved. For this reason, the processes and timing involved in their transient landscape evolution are poorly known. We explore the role of erodibility, basin geometry and flexural isostasy during the capture of internally-drained basins by means of numerical modelling techniques constrained by recent terrace cosmogenic dating and geomorphological analysis, addressing the issue as to why the Duero and Ebro rivers, draining two Cenozoic sedimentary basins in N Iberia with similar geographical dimensions and drainage histories, have undergone a markedly different erosion evolution leading to distinctly different present morphology. To evaluate how these intrinsic parameters affect the transient landscape evolution, we design a synthetic scenario inspired by those basins. The results show that, once a basin becomes externally drained, its drainage integration and erosion rates are strongly dependent on (1) the basin elevation above the base level; (2) the width of the topographic barrier, (3) its erodibility; and (4) the rigidity of the lithosphere. The results show that transient landscape evolution can last for tens of millions of years even in absence of tectonic activity and changes in base level or climate. Basins isolated by wide and resistant barriers such as the Duero Basin may undergo a multi-million-year time lag between drainage opening and basin-wide incision. In the case of the Duero Basin, this delay may explain the paradoxical time lag between the last lacustrine bulk sedimentation dated at 9.6 Ma and the onset of widespread basin incision variously estimated at 3.7 to 1 Ma., L’ouverture de bassins sédimentaires à drainage interne (endoréique) conduit souvent à un changement majeur du drainage, à la ré-excavation du remplissage sédimentaire du bassin et à un paysage transitoire. Le moment auquel ces ouvertures de bassin se produisent ne peut être daté que dans des cas exceptionnels où le plus jeune remplissage sédimentaire reste préservé. Pour cette raison, les processus et le calendrier impliqués dans l’évolution transitoire du paysage des bassins sont mal connus. Nous explorons le rôle de l’érodibilité, de la géométrie du bassin et de l’isostasie flexural lors de la capture de bassins endoréiques au moyen de techniques de modélisation numérique contraintes par les récentes datations cosmogéniques de terrasses fluviatiles et l’analyse géomorphologique. La question abordée c’est pourquoi les fleuves du Duero et de l’Ebro, drainant deux bassins sédimentaires cénozoïques du nord de l’Ibérie avec des dimensions géographiques et des histoires de drainage semblables, ont subi une évolution de l’érosion nettement différente conduisant à une morphologie actuelle nettement plus érodée au bassin de l’Ebre. Pour évaluer comment ces paramètres intrinsèques affectent l’évolution transitoire du paysage, nous concevons un scénario synthétique inspiré de ces bassins. Les résultats montrent que, une fois qu’un bassin à drainage interne est capturé et son drainage devient externe, l’intégration de son drainage et ses taux d’érosion dépendent fortement de (1) l’élévation du bassin au-dessus du niveau de base ; (2) la largeur de la barrière topographique ; (3) son érodabilité ; et (4) la rigidité de la lithosphère. Les résultats montrent que l’évolution transitoire du paysage peut se prolonger pendant des dizaines de millions d’années même en l’absence d’activité tectonique et de changements de niveau de base ou de climat. Les bassins isolés par des barrières larges et résistantes comme le bassin du Duero peuvent subir un décalage de plusieurs millions d’a

The dimensions, the geographical position and the complex geological history of the Iberian Peninsula makes it a unique and singular target to study its crustal and upper mantle structure and geodynamical evolution using geophysical methods. The lithospheric structure beneath Iberia has been investigated since the 1970’s using deep multichannel seismic reflection and refraction/wide-angle reflection profiling. Gravimetric and magnetic data were acquired following the deployment of permanent and temporary stations, mostly during the 1990’s. Beginning in the late 1990’s, the progressive use of Global Navigation Satellite Systems (GNSS) instruments contributed to monitor the present-day motions. During the last decades, numerous geological and geophysical surveys have investigated the Iberian lithosphere and upper mantle in the onshore and offshore regions, the most recent ones related to the TopoIberia project. The approach developed in this contribution is twofold. Firstly, we summarize the available geophysical information over Iberia, from focusing on the upper crust to the lithosphere-asthenosphere boundary and the transition zone marking the bottom of the upper mantle. Results of GNSS data, potential fields, controlled source seismic profiles, magnetotelluric data, body and surface wave tomography, receiver functions and 2D and 3D lithospheric modeling are reviewed and compared. Secondly, we focus on the areas of greater geodynamic interest and the regions where inconsistencies within the geophysical results, or contradictions in their tectonic interpretation exist, identifying the major questions that are still under debate. Besides shedding light to the state of knowledge and pointing out present-day research challenges, this review provides a tool for the integration of the diverse geophysical datasets with the surface geology and geodynamical processes that are interpreted to have built the complex geology of the Iberian Peninsula.

Catastrophic meltwater drainage from glacial Lake Agassiz has been hypothesised as a trigger for large-scale ocean circulation change initiating the Younger Dryas cold reversal. Here we quantify the flood discharge that formed the northwestern outlet of Lake Agassiz using a one-dimensional step-backwater model and a zero-dimension gradual-incision model. Applying these two independent models, we estimate a peak discharge range of 1.8-2.5 × 106 m3 s-1 and a flood volume of ∼21,000 km3. Such a discharge can only be derived from Lake Agassiz rather than one of the two smaller regional glacial lakes: Churchill or Meadow. When coupled with existing ice margin chronologies, these results demonstrate that the northwestern outlet of Lake Agassiz provides a viable link for catastrophic meltwater to drain to the Arctic Ocean over a 5-10 month period during the Younger Dryas, though it is unclear whether this was near its beginning.

Fluvial terraces are valuable records to study and characterize landscape evolution and river response to base level lowering, and to decipher coupled responses between fluvial incision and regional tectonics. The opening of closed basins has a strong impact on fluvial dynamics, as it involves an abrupt base level lowering that accelerates landscape fluvial dissection. This study focuses on the time response of the Duero Basin, the largest and best preserved among the Cenozoic basins of the Iberian Peninsula, to exorheism. Fluvial incision due to basin opening has developed up to 13 un-paired strath terraces along the south margin of the Duero river, distributed at relative heights up to +136–128 m compared to the modern floodplain. Paired 10Be–26Al cosmogenic isotope depth profiles from six fluvial terraces, located ca. 30–80 km upstream from the opening zone, suggest Pleistocene ages for almost the entire fluvial terrace staircase (from T3 at +112 –107 m, to T12 at +13–11 m). The terrace density and the total lowering of the terrace surface, key parameters in limiting terrace exposure ages, were estimated based on field and geomorphological data. Apparent burial durations and basin denudation rates deduced from inherited 10Be–26Al concentrations provide valuable information on basin evolution. Apparent basin denudation rates remained relatively low (<3–6 m·Ma−1) during the Pliocene, and doubled (8–13 m·Ma−1) during the Early Pleistocene (ca. 2–1 Ma) possibly showing a lower proportion of recycled sediments. Time averaged incision rates deduced from terraces in the study area and along some tributaries show that incision rates are higher close to the opening site (122–<250 m·Ma−1) than towards the upstream part of the catchment (88–68 m·Ma−1), evidencing the retrogressive travel of the erosive wave nucleated at the opening site. © 2020 Elsevier B.V.

The Messinian salinity crisis was an extraordinary event that resulted in the deposition of kilometre-thick evaporite sequences in the Mediterranean Sea after the latter became disconnected from the world's oceans. The return to fully and stable marine conditions at the end of the crisis is still subject to debate. Three main hypotheses, based on geophysical and borehole data, onshore outcrops and climate simulations, have been put forward. These include a single-stage catastrophic flood, a two-step reflooding scenario, and an overspill of Paratethyan water followed by Atlantic inflow. In this study, two research questions are addressed: (i) Which event marked the termination of the Messinian salinity crisis? (ii) What was the sea level in the eastern Mediterranean Sea during this event? Geophysical data from the western Ionian Basin are integrated with numerical simulations to infer that the termination of the crisis consisted of a single-stage megaflood following a sea level drawdown of 1900 m. This megaflood deposited an extensive sedimentary body with a chaotic to transparent seismic signature at the base of the Malta Escarpment. Fine, well-sorted sediments are predicted to have been deposited within the thicker sections of the flood deposit, whereas a more variable distribution of coarser sediments is expected elsewhere. The north-western Ionian Basin hosts evidence of episodic post-Messinian salinity crisis slope instability events in the last ~1.8 Ma. The largest of these emplaced a >200 km3 deposit and is associated with failure of the head of Noto Canyon (offshore SE Sicily). Apart from unravelling the final phase of the Messinian salinity crisis and the ensuing stratigraphic evolution of the western Ionian Basin, our results are also relevant to better understand megafloods, which are some of the most catastrophic geological processes on Earth and Mars. © 2020 Elsevier B.V.

Fluvial terraces are used as geomorphic indicators for deciphering long-term landscape evolution. Knowing the distribution of fluvial terraces is essential for establishing former river profiles and their tectonic significance, for studying climate-modulated processes of terrace development, or for defining fluvial network adjustments in response to sudden base-level changes like those produced by fluvial captures. Multiple methods for automatic map production have been proposed based on the comparison of morphometric indices with those of the modern river course. Here we propose an alternative method to identify flat surfaces and scarps separating them from digital elevation models without setting comparisons with a modern river course and thus fully applicable to study flat landforms whatever their origin. Its application to the low-relief landscape of the Cenozoic Duero basin has allowed the improvement of previous geomorphological maps and the analysis of fluvial network adjustments in response to a sudden base-level fall after the opening of the Neogene endorheic basin towards the Atlantic Ocean. Reconstructed terrace long-profiles suggest an initial episode of fast vertical incision followed by a period of repeated planation–aggradation–incision with the formation of 14 to 13 unpaired terrace levels. Changes observed in the pattern of terrace profiles are discussed with regard to changes in regional tectonics and base-level variations. © 2019 John Wiley & Sons, Ltd. © 2019 John Wiley & Sons, Ltd.

Correction to: Scientific Reports https://doi.org/10.1038/s41598-019-54374-w, published online 29 November 2019

About six million years ago, the Mediterranean Sea underwent a period of isolation from the ocean and widespread salt deposition known as the Messinian Salinity Crisis (MSC), allegedly leading to a kilometer-scale level drawdown by evaporation. One of the competing scenarios proposed for the termination of this environmental crisis 5.3 million years ago consists of a megaflooding event refilling the Mediterranean Sea through the Strait of Gibraltar: the Zanclean flood. The main evidence supporting this hypothesis is a nearly 390 km long and several hundred meters deep erosion channel extending from the Gulf of Cádiz (Atlantic Ocean) to the Algerian Basin (Western Mediterranean), implying the excavation of ca. 1000 km3 of Miocene sediment and bedrock. Based on the understanding obtained from Pleistocene onshore megaflooding events and using ad-hoc hydrodynamic modeling, here we explore two predictions of the Zanclean outburst flood hypothesis: 1) The formation of similar erosion features at sills communicating sub-basins within the Mediterranean Sea, specifically at the Sicily Sill; and 2) the accumulation of the eroded materials as megaflood deposits in areas of low flow energy. Recent data show a 6-km-wide amphitheater-shaped canyon preserved at the Malta Escarpment that may represent the erosional expression of the Zanclean flood after filling the western Mediterranean and spilling into the Eastern Basin. Next to that canyon, a ~1600 km3 accumulation of chaotic, seismically transparent sediment has been found in the Ionian Sea, compatible in age and facies with megaflood deposits. Another candidate megaflood deposit has been identified in the Alborán Sea in the form of elongated sedimentary bodies that parallel the flooding channel and are seismically characterized by chaotic and discontinuous stratified reflections, that we interpret as equivalent to gravel and boulder megabars described in terrestrial megaflood settings. Numerical model predictions show that san

Creep due to ice flow is generally thought to be the main cause for the formation of crystallographic preferred orientations (CPOs) in polycrystalline anisotropic ice. However, linking the development of CPOs to the ice flow history requires a proper understanding of the ice aggregate's microstructural response to flow transitions. In this contribution the influence of ice deformation history on the CPO development is investigated by means of full-field numerical simulations at the microscale. We simulate the CPO evolution of polycrystalline ice under combinations of two consecutive deformation events up to high strain, using the code VPFFT (visco-plastic fast Fourier transform algorithm) within ELLE. A volume of ice is first deformed under coaxial boundary conditions, which results in a CPO. The sample is then subjected to different boundary conditions (coaxial or non-coaxial) in order to observe how the deformation regime switch impacts the CPO. The model results indicate that the second flow event tends to destroy the first, inherited fabric with a range of transitional fabrics. However, the transition is slow when crystallographic axes are critically oriented with respect to the second imposed regime. Therefore, interpretations of past deformation events from observed CPOs must be carried out with caution, particularly in areas with complex deformation histories.

The immense advances in computer power achieved in the last decades have had a significant impact in Earth science, providing valuable research outputs that allow the simulation of complex natural processes and systems, and generating improved forecasts. The development and implementation of innovative geoscientific software is currently evolving towards a sustainable and efficient development by integrating models of different aspects of the Earth system. This will set the foundation for a future digital twin of the Earth. The codification and update of this software require great effort from research groups and therefore, it needs to be preserved for its reuse by future generations of geoscientists. Here, we report on Geo-Soft-CoRe, a Geoscientific Software & Code Repository, hosted at the archive DIGITAL.CSIC. This is an open source, multidisciplinary and multiscale collection of software and code developed to analyze different aspects of the Earth system, encompassing tools to: 1) analyze climate variability; 2) assess hazards, and 3) characterize the structure and dynamics of the solid Earth. Due to the broad range of applications of these software packages, this collection is useful not only for basic research in Earth science, but also for applied research and educational purposes, reducing the gap between the geosciences and the society. By providing each software and code with a permanent identifier (DOI), we ensure its self-sustainability and accomplish the FAIR (Findable, Accessible, Interoperable and Reusable) principles. Therefore, we aim for a more transparent science, transferring knowledge in an easier way to the geoscience community, and encouraging an integrated use of computational infrastructure.

Knowledge of glacier changes and associated hazards is of great importance for the safety of the population and infrastructure in the mountainous region of High Mountain Asia. In this study, we assessed the impact of variations in glacier velocity, glacier surface elevation change, meteorological variables, and permafrost distribution on debris flows in Badswat and Shishkat catchments. In Badswat catchment, a debris flow initiated from the former glacial moraine on 17 July 2018. In Shishkat catchment, debris flows usually occur during summer months when air temperatures are highest. We conducted in-depth analyses of long-term in situ meteorological data, field evidence, and satellite images. We applied feature and offset tracking techniques to high-resolution optical and radar images from Landsat, Planet and Synthetic Aperture Radar during 2013–2019 to estimate glacier velocities. We used geodetic methods to estimate glacier surface elevation change. We analyzed the associations between debris flow occurrence, permafrost distribution, and the variations in the 0°C isotherm. Between 1995 and 2019, the increase in temperatures in July is statistically significant for most low- and high-elevation meteorological stations. In Badswat and Shishkat catchments, permafrost is distributed over most of the catchment area and in the debris flow source areas. In Badswat catchment, no significant variations in glacier velocity and elevation change were observed over the study period; however, all three glaciers showed slightly higher velocity toward the terminus during the debris flow events. The debris flow in Badswat catchment damaged infrastructure and blocked the Immit River. The lake created by the blockage of the river inundated 34 houses, a community hall, agricultural land, and other infrastructure such as roads and businesses. Glacier dynamics and seasonal changes in temperature in the permafrost zone could have contributed to debris flow initiation. Our results show tha