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Evidence for frequent, large landslides on the flanks of the volcanic edifices forming the Canary Islands include outstanding landslide scars and their correlative submarine and subaerial rock and debris avalanche deposits. These landslides involved volumes ranging from tens to hundreds of km3. The sudden entry of large volumes of rock masses in the sea may have triggered tsunamis capable of affecting the source and neighboring islands, with the resulting huge waves dragging coastal and seabed materials and fauna and redepositing them inland. Here, we present new geological evidence and geochronological data of at least five megatsunamis in Tenerife, Lanzarote, and Gran Canaria, triggered by island flank megalandslides, and occasionally explosive eruptions, during the last 1 million years. The exceptional preservation of the megatsunami deposits and the large area they cover, particularly in Tenerife, provide fundamental data on the number of tsunami events and run-ups, and allow proposals on the sources and age of the tsunamis. Tsunami run-up heights up to 290 m above coeval sea level, some of the highest known on Earth in recent geological times, were estimated based on sedimentological, geomorphological, paleontological, and geochronological data. The research results made it possible to estimate the recurrence of tsunamis in the archipelago during the last hundreds of thousands of years, and to establish relationships between tsunami deposits and the probable triggering island flank landslides., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

The Famatinian is a segment of the Ordovician Terra Australis accretionary orogen that stretched along the SW Margin of Gondwana from Australia to Colombia. The present knowledge of this orogenic segment still is incomplete. We present geochemistry and U–Pb SHRIMP zircon geochronology of igneous and metamorphic rocks from the Central Famatinian Domain, one of the several domains recognized by Rapela et al. (Earth Sci Rev 187: 259–285. https://doi.org/10.1016/j.earscirev.2018.10.006) that includes the northern Sierras Pampeanas and the southern Puna of North West Argentina. Six samples of igneous rocks (peraluminous granitoids, mafic and felsic rocks, volcanic/subvolcanic rocks) and six samples of associated meta-sedimentary rocks, all from the Puna were dated and chemically analysed. The results indicate that the Central Famatinian Domain is in turn a composite domain that includes a Cordilleran-type magmatic arc (ca. 470 Ma) and a yuxtaposed fault-bounded older terrain formed in an extensional setting at the very start of the Famatinian orogeny, between 480 and 485 Ma, i.e., shortly after the SW Gondwana margin switched from passive to active. This short period of extension with related sedimentation, volcanism and mainly granitoid plutonism has not been previously recognised. It occurred before the Cordilleran-type magmatic arc -that resulted from a magmatic flare-up between ca. 473 and 468 Ma-, set up coincident with a contractional phase. The evidence confirms that accretionary orogeny results from tectonic switching (pull–push orogeny) and that the extensional and contractional phases are of relatively short duration., El cinturón Famatiniano es un segmento del orógeno acreccionario ordovícico Terra Australis, que se extendía a lo largo del margen SW de Gondwana desde Australia hasta Colombia. El conocimiento de este cinturón es todavía muy incompleto. En este trabajo se ha realizado geoquímica y geocronología U-Pb SHRIMP en circón en rocas ígneas y metamórficas del Dominio Famatiniano Central (Rapela et al., 2016) en el norte de las Sierras Pampeanas y el sur de la Puna en el noroeste de Argentina. Se han datado y analizado químicamente seis muestras de rocas ígneas (granitoides peraluminosos y rocas volcánicas/subvolcánicas maficas y felsicas) y seis muestras de rocas metasedimentarias asociadas, de la Puna meridional, principalmente. Los resultados indican que el Dominio Famatiniano Central es un dominio compuesto, que incluye un arco magmático de tipo Cordillerano con magmatismo de tipo I (ca. 470 Ma) y un terreno más antiguo, yuxtapuestos en la actualidad mediante fallas ándicas. Este último se formó en un contexto de extensión al comienzo de la orogénesis Famatiniana, entre ca. 480 y 485 Ma., en el margen SO de Gondwana, poco después de que cambiara de pasivo a activo. Este breve período de extensión, con sedimentación relacionada, vulcanismo y, principalmente, plutonismo granitoide, no había sido reconocido previamente y tuvo lugar antes de que se instalara el arco magmático de tipo Cordillerano como resultado de un flare-up magmático entre 473 y 468 Ma, coincidente, a su vez, con una fase de contracción. Esta evidencia confirma que la orogénesis acreccionaria es el resultado de la permutación tectónica (tectonic switching) entre fases de extensión y contracción (pull-push orogeny) y que estas son de duración relativamente corta., Ministerio de Economía y Competitividad (MINECO), Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

© 2021 American Meteorological Society. This work has been funded by the National Science Foundation, Grant AGS-1733818. P. Z.-G. acknowledges support by Santander UCM Grant PR87/19-22537. Simulations were performed on computational resources managed and supported by Princeton Research Computing, a consortium of groups including the Princeton Institute for Computational Science and Engineering (PICSciE) and the Office of Information Technology’s High Performance Computing Center and Visualization Laboratory at Princeton University. We thank the anonymous reviewers for constructive comments that helped improve the manuscript., This work investigates the characteristics of westward-propagating Rossby modes in idealized global general circulation models. Using a nonlinear smoothing algorithm to estimate the background spectrum and an objective method to extract the spectral peaks, the four leading meridional modes can be identified for each of the first three zonal wavenumbers, with frequencies close to the predictions from the Hough modes obtained by linearizing about a state of rest. Variations in peak amplitude for different modes, both within a simulation and across simulations, may be understood under the assumption that the forcing of the modes scales with the background spectrum. Surface friction affects the amplitude and width of the peaks but both remain finite as friction goes to zero, which implies that some other mechanism, arguably nonlinear, must also contribute to the damping of the modes. Although spectral peaks are also observed for the precipitation field with idealized moist physics, there is no evidence of mode enhancement by the convective heating. Subject to the same friction, the amplitude of the peaks are very similar in the dry and moist models when both are normalized by the background spectra., Universidad Complutense de Madrid/Banco de Santander, National Science Foundation, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

The coastal zone in which the lagoons of La Mata and Torrevieja (Eastern Spain) developed can be described as a compilation of geo-hazards typical of the Mediterranean realm. This study has focused mainly on those linked to recent tectonics. Extensive use of the amino acid racemization dating method allowed us to establish the evolution of all the geomorphological units differentiated in the area, the most striking manifestation being at the La Mata Lagoon Bar, where MIS 5 deposits settled on MIS 7 sediments along a marked erosive unconformity, thereby attesting coastal uplift between these two stages. In addition, recent uplift processes were reflected on stepped abrasion platforms and, in some cases, enormous boulders were transported over these platforms by extreme surge waves. Furthermore, we obtained feasible evidence that, during the end of MIS 5, an earthquake with an offshore epicenter linked to Torrevieja Fault, Bajo Segura Fault or the set of faults linked to the former, was responsible for tsunami surge deposits represented in accumulations of randomly arranged and well-preserved Glycymeris and Acanthocardia shells. Recent catastrophic effects linked to the earthquakes were also detected. In this regard, comparison of the paleontological and taphonomic analyses allowed us to discern between wave and tsunami surge deposits. Therefore, evidence of these hazards undoubtedly points to important future (and present) erosive and/or catastrophic processes, which are enhanced by the presence of tourist resorts and salt-mining industry. Thus, these sites are also threatened by future increases in sea level in the context of warmer episodes, attested by raised marine fossil deposits. At the north of Cervera Cape, beaches will be eroded, without any possibility of sediment input from the starved Segura River delta. At the south of this cape, waves (and tsunamis) will erode the soft rocks that built up the cliff, creating deep basal notches., Ministerio de Ciencia e Innovación (MICINN), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Oblique convergent margins, like the subduction of Phoenix beneath the South American plate during Jurassic and Early Cretaceous times, are characterized by strain partitioning and a positive feedback loop between strike-slip deformation and magma ascent along the magmatic arc. Located in the Coastal batholith of northern Chile, the Flamenco pluton is one of the youngest Andean intrusives emplaced in the western active margin of South America. Besides an older SW domain of granodioritic rocks (c.a. 213 Ma), the NW and E domains of the Flamenco pluton were emplaced between 194 and 186 Ma. They present a normally zoned structure constituted by external gabbroic to Qtz-dioritic magmatic facies and tonalites and granodiorites located in inner areas of the intrusive body. These domains are separated by a central strip of stretched coarse-grained Crd-schists that presents ductile asymmetrical folding and S–C structures that point to the NW-directed displacement of the E domain of the pluton. This syn-emplacement shear zone shows kinematic compatibility and continuity to the north and south with folded and mylonitic metasediments out of the contact aureole of the pluton. Together, these segments constitute a large, steeply dipping sigmoidal structure of average N–S direction; the called here Chañaral transcurrent shear zone. Contemporary to the emplacement of the Flamenco pluton, slight variations in the trend of the crustal-scale structure generated strike-slip and transpressive sectors along the Chañaral shear zone, which favored the access of intruding magmas to the final emplacement level. As a paradigmatic example, the curviplanar Flamenco shear zone, an internal, magmatic branch of the main structure that traverses the E domain of the pluton, is defined by the sinistral and reverse shearing under magmatic conditions of the previously mingled mafic and felsic batches. Consequently, the transpressive Flamenco shear zone is interpreted as an ascent conduit where gabbroi, FONDECYT, DIUDA, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

© 2021 by the authors. Funding: This research was funded by the European Union’s Horizon 2020 research and innovation program grant number 776661 (SOCLIMPACT project)., The progressive energy transition to systems with higher shares of renewable energy is particularly important in islands regions, which are largely dependent on energy imports. In this context, to assess the impact of climate change on renewable energy resources during the 21st century is crucial for polycimakers and stakeholders. In this work, we provide an overview of wind and photovoltaic (PV) resources, its variability and complementarity between them, as well as their future changes, in the Canary Islands and surrounding areas. Variability is assessed through the analysis of energy droughts (low-productivity periods). In addition, a sensitivity test is performed to find the optimal combination of PV (photovoltaic) and wind that reduce energy droughts and the persistence of that conditions at a local scale. A set of climate simulations from the MENA-CORDEX runs are used, in present and future climate (2046-2065, 2081-2100) for two different scenarios (RCP2.6, RCP8.5). Results show different changes in wind productivity depending on the scenario: a decrease in RCP2.6 and an increase in the RCP8.5. PV experienced a subtle decrease, with some exceptions. Changes in variability are small and the complementarity test shows that high shares of PV energy (above 50%) reduce both, energy droughts and the persistence of drought conditions., European Commission, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

The accurate estimation of flood risk depends on, among other factors, a correct delineation of the floodable area and its associated hydrodynamic parameters. This characterization becomes fundamental in the flood hazard analyses that are carried out in urban areas. To achieve this objective, it is necessary to have a correct characterization of the topography, both inside the riverbed (bathymetry) and outside it. Outside the riverbed, the LiDAR data led to an important improvement, but not so inside the riverbed. To overcome these deficiencies, different models with simplified bathymetry or modified inflow hydrographs were used. Here, we present a model that is based upon the calibration of the Manning’s n value inside the riverbed. The use of abnormally low Manning’s n values made it possible to reproduce both the extent of the flooded area and the flow depth value within it (outside the riverbed) in an acceptable manner. The reduction in the average error in the flow depth value from 50–75 cm (models without bathymetry and “natural” Manning’s n values) to only about 10 cm (models without bathymetry and “calibrated” Manning’s n values), was propagated towards a reduction in the estimation of direct flood damage, which fell from 25–30% to about 5%., MINEICO/AEI/FEDER, UE, National System of Youth Guarantee, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Se realiza un análisis por prospección geofísica mediante tomografía eléctrica (ERT, electrical resistivity tomography) en el abrigo de Sopeña (Asturias) y su zona inmediata. El abrigo contiene un interesante yacimiento del Paleolítico Medio superior y Paleolítico Superior inicial, desvelado en un sondeo arqueológico de hasta 3 metros de profundidad sin haber alcanzado la base rocosa. Su entrada actual está protegida por grandes bloques caídos de la cornisa, recubiertos por gruesas coladas estalagmíticas. Esta disposición posiblemente atestigua una posición original de la zona de ocupación humana más interna, dentro de una cueva de mayores dimensiones. Mediante este análisis hemos localizado varios posibles rellenos sedimentarios a cierta profundidad en el exterior del abrigo. Se abre así la posibilidad de muestrear en un futuro esos rellenos, en busca de posibles niveles de ocupación más antiguos., A geophysical survey analysis is carried out using electrical resistivity tomography (ERT) in the Sopeña shelter (Asturias) and its immediate area. The shelter contains an interesting Upper Middle Palaeolithic and early Upper Palaeolithic site, revealed in an archaeological test pit up to 3 metres deep without having reached the bedrock. Its current entrance is protected by large blocks fallen from the ledge, covered by thick stalagmitic flows. This arrangement possibly testifies to an original position of the innermost human occupation zone, inside a larger cave. Through this analysis we have located several possible sedimentary fills at a certain depth on the outside of the shelter. This opens up the possibility of sampling these fills in the future, in search of possible older occupation levels., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

© 2021. American Geophysical Union. All Rights Reserved. Financial support was given by the Spanish Ministry of Science and Innovation thorough the projects CERAC (HAR2016-75133-C3-1-P), CONCERAC (HAR2016-75133-C3-3-P), SPYKE (CGL2017-87015-P), SuMATE (PID2020-113316GB-I00) and PULSES 5.K (PID2020-117105RB-I00). R. Bonilla-Alba thanks the FPI fellowship (PRE2018-085949) associated with the SPYKE project. This study has been also funded by the Ramón y Cajal program (contracts of M. Gomez-Paccard and V. Martinez-Ferreras, refs. RYC-2013-14405 and RYC-2014-15789). The authors wish to acknowledge the professional support of the CSIC Interdisciplinary Thematic Platform Open Heritage: Research and Society (PTI-PAIS). E. Beamud thanks the Geomodels Research Institute (UB) and the Grup de Geodinamica i Analisi de Conques-2017SGR596 (Generalitat de Catalunya). A. Palencia-Ortas thanks the PTA contract of the Spanish Ministry of Science and Innovation. Special thanks to S. Pidaev from the Academy of Sciences of the Republic of Uzbekistan for its great help during the sampling campaign in Uzbekistan. The authors also thank our colleagues from the paleomagnetism group of Madrid, especially S. A. Campuzano and E. Delso, and the great archeological team that helped us during the archeomagnetic field campaigns in Uzbekistan. Additional information upon request to or . The Editor, Mark Dekkers and reviewers, Lisa Tauxe and Evdokia Tema are sincerely acknowledged for their constructive comments on our manuscript., Recent paleomagnetic studies have shown that important short-lived intensity fluctuations occurred during the first millennium BCE. However, the knowledge of the spatial and temporal extension of these features is still limited by the scarce availability of robust data. In this study we focus on the study of the intensity decrease that took place in Central Asia during the second half of the 1st millennium BCE after the high intensities that characterized the Levantine Iron Age Anomaly. Since previous archeointensities available for this period and region were obtained without accomplishing modern standards of quality, we present here new archeointensities that are derived from classical Thellier and Thellier experiments, including partial thermoremanent magnetization (pTRM) checks, thermoremanent magnetization (TRM) anisotropy and cooling rate corrections at the specimen level. The new 51 archeointensities, together with previous archeointensities, have been used to present a new local paleosecular variation curve for Central Asia. The results confirm the existence of an important geomagnetic field intensity decrease in South Uzbekistan from the 4th century BCE to the end of the 1st century BCE associated with rates of changes up to -15 mu T/century. A critical analysis of the archeointensity global database indicates that this feature was present at continental scale, from Western Europe to Central Asia. However, this trend is not identified in other regions such as Japan or Mexico. Finally, the comparison with the dipole moment derived from recent global geomagnetic field reconstructions suggests a strong influence of non-dipolar sources upon this continental intensity feature., Ministerio de Ciencia e Innovación (MICINN), Ministerio de Economía y Competitividad (MINECO), Ministerio de Ciencia e Innovación (MICINN), Generalitat de Catalunya, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

The deep structure of the Alhama de Murcia Fault (AMF) is characterized by means of the analysis of surface waves identified in shallow high resolution seismic reflection data. Multichannel analysis of surface waves (MASW) is used to unravel the 2-D S-wave velocity model and image the depth geometry of the fault system. The study area includes segments of the fault located in La Salud area. Two approaches have been used to achieve a well constrained velocity model in the AMF fault zone. Conventional seismic reflection processing work flow has been used to clean the seismic data and increase its S/N ratio. Occam’s approach has been used to invert the digitized surface wave dispersion curves. 1D shear wave velocity-depth profiles were estimated in shot and CDP domains. Relatively well resolved 2D velocity-depth models were obtained by com- posite of the 1D Velocity-depth functions. These composite 2D-velocity models are able to constrain the depth geometry of the fault zone up to 100 m depth. The fault zone is indicated by a relatively broad low velocity anomaly that correlates with the fault’s surface expression., La estructura profunda de la falla de Alhama de Murcia (AMF) ha sido caracterizada mediante el análisis de ondas superficiales identificados en datos de reflexión sísmica superficial de alta resolución. El análisis multicanal de ondas de superficie (MASW) es usado para desentrañar un modelo 2D de Vs y para obtener imágenes de la geometría del sistema de fallas en profundidad. El área de estudio incluye segmentos de la AMF ubicados en el área de La Salud. Se han utilizado dos enfoques para lograr modelos de velocidad bien restringidos de la zona de falla. Por un lado, se han limpiado los datos utilizado un flujo de procesado convencional diseñado para aumentar su ratio de señal/ruido. Por el otro, se ha usado el enfoque de Occam para invertir las curvas de dispersión de ondas de superficie digitalizadas. Los perfiles 1D de profundidad de las Vs fueron estimados en los dominios de disparo y de CDP. Se obtuvieron modelos de velocidad-profundidad 2D relativamente bien resueltos mediante la interpolación de las funciones de velocidad-profundidad 1D. Estos modelos de velocidad 2D ayu- dan a restringir en profundidad la geometría de la zona de falla hasta los 100 m que se caracteriza por una anomalía de baja velocidad relativamente amplia que se correlaciona en la superficie con la expresión de la falla., Ministerio de Ciencia e Innovación (MICINN), ICTJA-CSIC, Ministry of Education and Culture of the Republic of Indonesia, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Since the beginning of the XXI Century, our society has witnessed a number of catastrophic earthquakes with devastating consequences (e.g., Sumatra 2004, Haiti 2010, Japan 2010, Nepal 2015, Italy 2009 and 2016). Localizing the active faults and understanding their earthquake history is key to improve modern probabilistic seismic hazard assessment (PSHA) and, thus, to mitigate the consequences of future events. Seismicity models to characterize the earthquake frequency in a region in PSHA studies have been traditionally based on archaeological, historical and instrumental earthquake records. However, the rapid advance of active tectonics and paleoseismological studies has resulted in the development of seismicity models for faults, since they allow characterizing the active faults, reconstructing their 3D geometry at depth, and determining their past earthquake history and seismic potential based on the interpretation of the geological record. Traditionally, active tectonics and paleoseismological research had been mainly conducted to study onshore active faults. However, the occurrence of the offshore Sumatra (2004) and Japan (2010) earthquakes and consequent tsunamis, which caused tens of thousands of casualties and extensive and severe damage and economic losses, have brought into sharp focus the need to better understand the geohazards related to submarine active faults. In the last few years, the availability of offshore geological and geophysical data at various scales (e.g., deep and shallow borehole, wide angle seismic profiles, tomography, 3D and 2D seismic reflection surveys, high resolution bathymetry or seafloor imaging) has allowed for a better definition of offshore fault systems. These studies focused on accurately constraining the kinematic, architecture and linkage of active faults, and, in some cases, identify recent earthquake ruptures or recognize and date individual events. In addition, underwater active tectonics and paleoseismological studies b, Unión Europea. Horizonte 2020, Ministerio de Ciencia e Innovación (MICINN), Comunidad de Madrid, Centro de Excelencia Severo Ochoa, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

A total of 36 rock slides were selected for analysing a probable seismic source in the active Andean Precordillera (31°–33°S), the most seismic region of Argentina. Seven of these slope instabilities were selected for in-depth analysis in the field as a function of the most frequent class, lithological susceptibility and field accessibility. Reconstructing the topography previous to collapse and using geotechnical parameters extracted from field data in conjunction with geomechanical testing, the rock slides were modelled using pseudostatic limit equilibrium analyses for the obtention of the critical probabilistic acceleration (ac) required to generate the instability under unsaturated conditions and considering both the horizontal and vertical seismic components. To perform a probabilistic estimation of ac, the parameters in relation to the generalized Hoek–Brown failure criterion were selected to operate statistically using 2D SLIDE 8.0 software. Applying inversely Ground Motion Prediction Equations (GMPEs) and concerning the distance to the studied paleolandslide, a possible earthquake inducing a seismic coefficient (kh) ≥ ac was determined. Therefore, a near active fault(s) capable of generating an earthquake magnitude inducing a Peak Ground Acceleration (PGA) ≥ ac at the paleolandslide location was designated as the possible seismogenic source of the slope instability. Intersecting these results, potential paleoseismic events which could have caused several slope instabilities were determined. Thus, a new methodology was developed, which allowed to determine the main seismogenic sources capable of inducing the modelled instabilities in each studied subarea in the Precordillera., National University of Cuyo, Ministry of Defence, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

The Cubito-Moura Unit is a high-P metamorphic succession that occurs in the southern part of the Ossa-Morena Complex (SW Iberian Massif). It includes a series of metasedimentary, metafelsic and metamafic rocks affected by a high-P, low to intermediate-T metamorphic event during Late Devonian times. Geochemistry of the metabasic rocks reveals that the generation of the protoliths occurred in a supra-subduction zone setting during Late Ediacaran to Early Ordovician times, either in a back-arc or fore-arc context. The eclogites contain atoll-like garnets, omphacite, amphibole, phengite (up to Si = 3.38 apfu), paragonite, rutile and quartz. Thermodynamic modelling in the MnNCKFMASTH system indicates a high-P metamorphic event at ~24 kbar and ~ 585 °C followed by a thermal peak at ~19 kbar and ~ 630 °C, and a subsequent exhumation to ~15 kbar. This P-T path indicates deep subduction at c. 370 Ma of this arc-related section. The lithostratigraphy and tectonothermal evolution of the Cubito-Moura Unit are equivalent to that of a number of units along the Iberian, Armorican and Bohemian massifs that can be correlated as a part of the same Basal Allochthonous Terrane. These units define a single Late Devonian high-P, low- to intermediate-T metamorphic belt developed during the first stages of the Variscan Orogeny., Ministerio de Economía, Industria y Competitividad (MINECO), Ministerio de Ciencia e Innovación (MICINN), FCT (Portugal), IUGS-UNESCO, Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

Hyperextended margins are very heterogeneous along the entire length of the margin, so the definition of tectonic domains made exclusively from 2D seismic sections presents serious limitations. In this work we present an approach of the 3D crustal-scale structure of the West Iberia margin (WIM) by modelling eight lithospheric sections, using seismic, wells and gravity data. The continuous nature of gravity data allowed us to propose a new map of tectonic domains within the WIM. Maps of total horizontal (THD) and vertical gradients (dZ) of Bouguer anomaly have been calculated and compared with other criteria such as the crustal structure and thinning factor. This comparative analysis has been carried out on a section proposed as a model for the Western Iberian Margin (Tugend et al. in Tectonics, 2014; Cadenas et al. in Tectonics 37:758–785, 2018), and on four 2 + 1/2D gravimetric models transversal to the margin. The results point out a significant variation in the absolute values of Bouguer anomaly, thinning factor and crustal structure along the margin and, therefore, of the position of the different domain boundaries. Clear patterns that correlating the Bouguer anomaly signal and its derivatives to the tectonic domain are evidenced. Most significantly, the necking-zone and its transition to the hyperextended domain are characterized by high values of the THD of the Bouguer anomaly. The observed patterns in Bouguer anomaly and its derivatives provide a solid constraint for mapping the boundaries between different tectonic domains along the margin, even in those areas where limited deep seismic information could lead to uncertain interpretations. The results of this work can also inform on the general kinematics of the WIM., Ministerio de Ciencia e Innovación (MICINN), Comunidad de Madrid, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

The reactivation of very large landslides may cause severe damage to society. Its prevention and management requires detailed information on the geometry and structure of these landslides, but the use of standard techniques (boreholes) may be prohibitive from an economic point of view. To overcome these difficulties, geophysical techniques are of special interest because they allow for studying very large areas at a reasonable cost. In this paper, we present a case study wherein the analysis of ambient noise allowed us to produce a model of a large landslide near Granada (southern Spain). The geometry and location of the failure zone, as well as the assessment of the state of involved materials, were estimated by combining two available boreholes and different geophysical techniques (downhole tests and the spectral analysis of ambient noise, horizontal to vertical spectral ratios (HVSR) and the frequency-wavenumber (f-k) methods). The results have allowed us to differentiate between values within the landslide mass with respect to those of stable materials, and to perform for the first time a comprehensive geological model of this unstable mass. Differences were also observed within the landslide mass (earth flow vs. slide zones), which are attributed to differences in the degree of alteration and the disturbance of the internal structure of materials constituting the landslide mass. These results show that techniques based on the measurement of ambient noise are of special interest for studying very large, highly remolded landslide masses., Ministerio de Economía y Competitividad (MINECO)/FEDER, Junta de Andalucía, Universidad de Alicante, Universidad de Jaén, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

In all the Columbretes islands there are rocks with amphiboles, in many cases in accidental fragments within the tuffs. All of them are magnesium-hastingsites, more or less zoned and reabsorbed. The amphiboles of the central islands of the main N-S alignment have formed at lower temperature and pressure than the rest. The calculated formation depths are approximately the Moho depth for the area., En todas las islas Columbretes aparecen rocas con anfíboles, en muchos casos en fragmentos accidentales dentro de las tobas. Todos ellos son magnesio-hastingsitas, más o menos zonadas y reabsorbidas. Los anfíboles de las islas centrales de la alineación principal N-S, se han formado a menor temperatura y presión que el resto. Las profundidades de formación calculadas son aproximadamente las de la profundidad del Moho para la zona., Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

© 2021 Inter-Research., The lack of long-term, homogeneous snowfall records is a limitation in environmental studies. Statistical modelling holds potential to extend snowfall records back in time with a limited set of predictors: snow severity and winter-spring temperatures (with their variability) to reflect elevation influences. The annual number of snow days (SDY) in the Benevento Valley (southern Italy) was detailed for the period 1870-2018. Calibrated in the period 1870-1968 (R-2 = 0.85) and validated in the period 1969-2018 (R-2 = 0.67), the model developed here enabled the reconstruction of a time-series of SDY between 1645 and 2018. This unique series (the longest in southern Italy) shows that SDY peaked during the Little Ice Age (until similar to 1850), dominated by cold air masses or characterized by winter seasons extending until May (1655, 1684, 1763 and 1830) or June (1620). After the change-point detected in 1866, the modelled SDY time-series declined rapidly (Modern Warming Period, 1867-2018). The atmospheric conditions that favoured snowfall in the Benevento Valley throughout the study period were generally associated with an anomalous high-pressure system located over northern-northwestern Europe and a low in the eastern Mediterranean. This configuration allowed the incursion of cold continental air from the east-northeast into southern Italy. Our results are consistent with similar studies of snowfall in other European and mid-latitude regions of the northern hemisphere., Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

La cartografía y análisis de las facies acústicas que se determinan a partir de la interpretación y correlación de los perfiles sísmicos de muy alta resolución, es una herramienta muy útil para la caracterización de los procesos sedimentarios recientes y su distribución en ambientes marinos profundos. Este trabajo presenta el primer mapa de ecocarácter del Margen Continental de Galicia y las llanuras abisales adyacentes. El mapa se realizó sobre la base del análisis e interpretación de los datos de batimetría y reflectividad de las ecosondas multihaz SIMRAD EM12, EM120 y EM1002, y los perfiles sísmicos de muy alta resolución de la ecosonda paramétrica SIMRAD TOPAS PS18. Sobre la base de la morfología del fondo marino, la reflectividad y los caracteres del eco acústico, se identificaron 26 tipos de ecos en la secuencia sedimentaria más superficial. Estos tipos de eco se han clasificado en cuatro grupos principales: bien definidos, irregulares, hiperbólicos y ondulados. Esta información ha sido adquirida en el marco del ‘Programa de Investigación Científica de la Zona Económica Exclusiva Española’, coordinado por el Ministerio de Defensa, durante las campañas oceanográficas que se han realizado a bordo del BIO Hespérides del 2001 a 2003 y del 2006 a 2009., The acoustic facies mapping and analyses from the interpretation and correlation of very high resolution seis- mic profiles, is a very useful tool for the characterization of the recent sedimentary processes and their distribution in the deep-sea environments. This work presents the first echo-character map of the Galicia Continental Margin and the adjacent abyssal plains. The map was carried out on the basis of the analysis and interpretation of the bathymetry and reflectivity data from the SIMRAD EM12, EM120 and EM1002 multibeam echosounders, and the high resolution seismic profiles from the SIMRAD TOPAS PS18 parametric echosounder. Based on the seafloor morphology, backscatter and acoustic echo-characters, 26 echo types were identified in the uppermost sedimentary sequence. These echo-types have been classified into four main groups: Distinct, Irregular, Hyperbolic and Undulated echoes. This information has been acquired in the framework of the ‘Scientific Research Program of the Economic Exclusive Zone of Spain’, which is coordinated by the Defense Ministry, during the oceanographic cruises carried out on board of the R/V Hesperides in 2001 to 2003 and 2006 to 2009., Ministerio de Ciencia e Innovación (MICINN), Instituto Geológico y Minero de España, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

In 2003, 2006–2009, 2014 and 2015, seven oceanographic cruises were carried out onboard the Spanish R/V Hespérides in the Cantabrian Margin and the adjacent abyssal plains, covering anarea of 219,124 km2. Based on the combined analysis and interpretation of the bathymetric and reflectivity data obtained with multibeam echosounders (SIMRADEM12, EM120 and EM1002), and ultra-high-resolution reflection seismic records acquired with the SIMRAD TOPASPS18 parametric sounder, the mapping of the acoustic facies or echo-character at a scale of 1:1,200,000 has been carried out. Thirty types of echoes have been differentiated and gather into four main groups: Distinct, Irregular, Hyperbolic and Undulated. The echo-character depends on the acoustic response of the shallow sediment and these a bed morphology. Therefore, its analysis and characterization are basic for understanding recent and present-day sedimentary processes., Ministerio de Ciencia e Innovación (MICINN)/FEDER, Ministerio de Defensa, Universidad Complutense de Madrid, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

En este trabajo se analizan mediante campos potenciales (gravimetría y magnetismo) las estructuras salinas interpretadas previamente en el offshore de la Cuenca de Asturias. Para ello se han realizado los mapas de anomalías y tres modelos en 2+3/4D GRAV/MAG con datos coincidentes con un cubo sísmico 3D adquirido por Repsol en 2008. El análisis cuantitativo de los mapas y la modelización en 2+3/4D ha permitido reinterpretar la estructura del basamento y de las estructuras salinas hasta ajustar la señal GRAV/MAG. Estas modificaciones son significativas por debajo de los niveles de evaporitas, destacando la necesidad de introducir menor cantidad de sal, y una reinterpretación de la geometría del techo del basamento., In this work a potential field analysis (gravimetry and magnetism) of the salt structures interpreted in the offshore of the Asturias Basin. For this purpose, 2D processing of the anomaly maps and three models in 2+3/4D GRAV/MAG have been carried out with the data that coincide with a 3D seismic cube acquired by Repsol in 2008. The quantitative analysis of the maps and modeling has allowed the revaluation of the structure of the basement and salt structures until adjusting the GRAV/MAG signal. These modifications are significant below the levels of evaporites, highlighting the need to introduce less salt, and a new geometry of the basement top., Ministerio de Ciencia e Innovación (MICINN), Comunidad de Madrid, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Colonization of the water column by animals occurred gradually during the early Palaeozoic. However, the morphological and functional changes that took place during this colonization are poorly understood. The fossil record provides clear evidence of animals that were well adapted for swimming near the seafloor or in the open ocean, but recognising transitional forms is more problematic. Trilobites are a good model to explore the colonization of marine ecosystems. Here, we use computational fluid dynamics (CFD) to test between competing functional hypotheses in the Ordovician trilobite Placoparia. The CFD simulations exhibits hydrodynamics that promote detachment from the seafloor but also promote return to the seafloor following detachment, this is compatible with hopping locomotion. The results suggest that Placopara was not able to swim, but its hydrodynamics allowed it to hop long distances. This is consistent with the fossil record, as some ichnofossils show evidence of hopping. This type of locomotion could be useful to avoid predators as an escape mechanism. In addition, CFD simulation shows how the morphology of Placoparia is adapted to protect anterior appendices of the trunk and generate a ventral vortex that send food particles directly to the trilobite mouth. Adaptations in Placoparia allowed the first steps to evolved a new ecological habitat and consequently nektonization during the GOBE., Conferencia de Rectores de las Universidades Españolas (Acuerdos Transformativos 2021), Consejo Superior de Investigaciones Científicas (Acuerdos Transformativos 2021), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Enhancing resilience against flooding events is of great importance. Eastern Iberian Peninsula coastal areas are well known for high intensity rainfalls known as DANA or “cold drop”. Extreme records in 24 h can exceed the annual average of the historical series. This phenomenon occurs normally in autumn due to convective storms generated by the existence of cold air in the upper layers of the atmosphere combined with warm winds coming from the Mediterranean Sea. In many coastal areas of the Eastern Iberian Peninsula, their flat topography, sometimes of a marsh nature, and the natural (e.g., dune ridges) and man-made (e.g., infrastructures) factors, result in devastating flooding events of great potential damage and risk for urban and rural areas. In this context, this paper presents the case study of the town of Oliva (Valencia, Spain) and how in a flooding event the flow tends to spread and accumulate along the flat coastal strip of this populated area, causing great potential damage. From that point, the paper discusses the particular issues that flood studies should consider in such flat and heavy rainy areas in terms of the hydrological and hydraulic models to be conducted to serve as the key tool of a correct risk assessment. This includes the correct statistical simulation of rainfalls, the hydrological model dependency on the return period and the correct geometry definition of all possible water barriers. An analysis of the disturbance that climatic change effects may introduce in future flooding events is also performed., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

CRUE-CSIC (Acuerdos Transformativos 2021), In regions with slow-moving faults, the incompleteness of earthquake and fault data complicates the study of seismic hazard. The instrumental and historical seismic catalogs cover a short period compared with the long-time interval between major events. Paleoseismic evidence allows us to increase the time frame of actual observations, but data is still scarce and imprecise. Physics-based earthquake simulations overcome the limitations of actual earthquake catalogs and generate long-term synthetic seismicity. The RSQSim earthquake simulator used in our study reproduces the earthquake physical processes based on a 3D fault model that contains the kinematics, the long-term slip rates and the rate-and-state friction properties of the main seismogenic sources of a region. The application of earthquake simulations to the Eastern Betic Shear Zone, a slow fault system at southeastern Spain, allows the compilation of 100 kyr-synthetic catalogs of MW > 4.0 events. Multisection earthquakes and complete ruptures of some faults in this region, preferentially on strike-slip dominant ruptures, are possible according to our simulations. The largest MW > 6.5 events are likely as a result of jumping ruptures between the Carboneras and the Palomares faults, with recurrence times of < 20,000 years; and less frequently between the Alhama de Murcia and the Los Tollos faults. A great variability of interevent times is observed between successive synthetic seismic cycles, in addition to the occurrence of complex co-ruptures between faults. Consequently, the occurrence of larger earthquakes, even MW ≥ 7.0, cannot be ruled out, contrasting with the low to moderate magnitudes recorded in the instrumental and historical earthquake catalog., Ministerio de Ciencia e Innovación (MICINN), NZ SSIF, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Se describe un cabalgamiento cuaternario, que corta a una brecha sedimentaria que recubre la terraza de +5 m del río Ibor, en el extremo occidental de los Montes de Toledo. El sistema de cabalgamientos descrito ha condicionado la localización de abanicos aluviales fini-neógenos (“raña”), por lo que ha de considerarse como activo durante los últimos 9 Ma. El sismo asociado, superficial, se estima de una magnitud entre M 6-6.5. La rotura se localiza a menos de 20 km de la Central Nuclear de Almaraz (Cáceres)., A Quaternary overthrust is described, intersecting a sedimentary breccia covering the +5 m terrace of the Ibor River, at the western end of the Montes de Toledo. The resulting thrusting system has conditioned the location of fini-neogene alluvial fans ("raña"), so it has to be considered as active during the last 9 Ma. The associated, superficial earthquake is estimated to range between M 6-6.5 in magnitude. The rupture is located less than 20 km from the Almaraz Nuclear Power Plant (Cáceres)., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Controlling sediment produced by water erosion is the highest environmental challenge in steep, open pit sand mines located in erosive climates. Although restoration is impractical in active mine areas, sedimentation ponds are the Best Available Technique by the European Union to reduce sediment spillages from these environments. Few studies have described and supported such a solution with high resolution data. The María José mine is one of two active kaolin mines in the mining area of the Alto Tajo Natural Park, a highly erosive setting. It has a complex maintained pond system as a hydrologic and sedimentary control measure. In this landscape, mining can only be sustainable if clean water from production is ensured. The pond system retains sediment and water during a rain event, deposits the sediment, and eventually spills the water under controlled events. The María José spillages have been continuously monitored for suspended sediment concentration and water discharge at the mine outlet since 2012. During four years the efficiency of the pond system varied (96.7–99%), producing an average annual sediment yield of 5.6 Mg ha−1 y−1, a reduction of 98.4% compared with the sediment yield reported for similar local mines having no ponds. A quarter of this sediment was produced under controlled spillages allowing runoff management; the rest during large rainfall events when runoff decreased pond efficiency gives rise to an increase in suspended sediment concentration, as is typical of local natural rivers. Provided continuous maintenance, sediment ponds are shown to be a successful method to produce clean water. Successful pond efficiency implies that a mine produces water and sediment during baseflow conditions, allowing sufficient sediment volume to accumulate during rainstorms., Ministerio de Ciencia e Innovación (MICINN), Comunidad de Madrid, CAOBAR/UCM, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

The Lower Tagus Valley Fault, Portugal, has long been associated with the damaging earthquakes that affected the Greater Lisbon Area in historical times. These include a poorly documented earthquake that occurred in 1344, the relatively well-documented 1531 earthquake, and the most recent M6.0 1909 earthquake. In this work, we use a 0.5 m resolution LiDAR-based digital elevation model and a 0.5 cm resolution digital surface model based on UAV photogrammetry to accurately locate the fault scarps in the northernmost portion of the western fault strand and to select sites to perform paleoseimolological investigations. The paleoseismological and geochronological analysis performed in the Alviela trench site document the fault activity in the last 3000 years, including two earthquakes during historical times. We performed ground motion scenarios for 20 km, 40 km, and 60 km ruptures including the trench site. The ground motion fields obtained for the 40 km and 60 km ruptures are in agreement with most macroseismic intensity data available for the 1531 earthquake, implying a magnitude in the range M6.8–7.4. However, the degree of deformation preserved in the trench suggests a value closer to the lower magnitude bound. The intensity level observed in Lisbon in 1531 (IX) is lower than the modeled intensities for all considered scenarios and could be related to a particularly high level of vulnerability of the building stock., Portuguese Foundation for Science and Technology, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

This research documents the successful application of a novel holistic approach to return land degraded over thousands of years of use to full ecological function. The surroundings of the Somolinos hamlet in Central Spain illustrate a millennial history of land transformation and degradation by agrarian and extractive activities exacerbated at the second half of the 20th century by mechanized mining. This land stewardship history was culminated by a recent intervention of geomorphic-based ecological restoration and its monitoring. Historic anthropogenic processes which triggered gully erosion were intense deforestation for agriculture and grazing, and construction materials quarrying. From 1963 to 2006 mechanized quarrying operated over ancient extractive landforms. In 2007, a conventional rehabilitation mitigated risks but failed at controlling erosion and promoting soil and vegetation reestablishment. A geomorphic-based ecological restoration was accomplished since 2011. The GeoFluv-Natural Regrade CAD software was used for geomorphic landform design, and construction was completed with a carbonatic colluvium topdressing supplemented with a manure-amended soil, that was seeded with grasses. The whole process was a truly complete application of ecological engineering. One of the main purposes of this research was to carefully scrutinize the completed project, to evaluate its effectiveness and, if any deficiencies were found, to analyze their causes, so that they could be avoided in the future. Therefore, the landscape evolution and erosional behaviour of the restored area has been monitored from 2011 to 2020 through a time-lapse sequence of several oblique aerial photos, and by comparing topographies through Digital Elevation Models (DEMs) of Difference (DoDs). Those topographies were surveyed with differential GPS (DGPS) and with Structure from Motion (SfM) combined with Unmanned Aerial Vehicles (UAVs). This monitoring revealed: (a) landscape healing and diversifi, Ministerio de Ciencia e Innovación (MICINN), Comunidad de Madrid, Junta de Comunidades de Castilla-La Mancha, Universidad Complutense de Madrid, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

CRUE-CSIC (Acuerdos Transformativos 2021), A Silurian regional tectonometamorphic event has been widely recorded by different geochronological methods in the Sierras Pampeanas, NW Argentina and the Precordillera. It took place between ca. 445 and 420 Ma after the regional Hirnantian (late Ordovician) glaciogenic sedimentation. Three domains are recognized. 1) The eastern Sierras Pampeanas and the Puna mainly record focused westward ductile thrusting and heating. 2) In the westernmost Sierras Pampeanas (Maz, Espinal, and Umango) garnet-amphibolite facies metamorphism, penetrative foliation development and westward ductile thrusting (nappes) took place. 3) In the Precordillera, the Rinconada formation of Silurian age consisting of chaotic olistoliths of Ordovician and Cambrian age correlates with this event. The three domains correspond to the hinterland, the internal hot and thickened metamorphic core, and the foreland respectively of an orogenic belt. Remarkably no Cordilleran-type magmatism of this age has been recorded. The regional importance of this event was overlooked so far., Ministerio de Economía y Competitividad (MINECO), Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

The dune fields of the National and Natural Parks of Doñana are considered one of the most outstanding dune fields in Western Europe. They are located at the west margin of the Guadalquivir river estuary. The accumulation of aeolian sands partly blocks the connection between the ample Guadalquivir River estuary and the Gulf of Cádiz in the Atlantic Ocean. The sand units form a large oval dome, the “Abalario Dome” which connects with the large Doñana Spit Bar where dune systems accumulated as well, at least in part coevally with the spit growth. The most frequent dune morphologies are parabolic or transverse. The degree of activity was classified as stable, semi-active and active. Most stable dunes concentrate on the Abalario Dome, whereas active dunes occur mainly on the Doñana spit bar. Relative chronology was established from the superposition of dune Systems and Subsystems deduced from photogeology coupled with field surveys, orthophotos, and oblique and 3D images. Sampling and radiogenic dating (Optically Stimulated Luminescence-OSL) allowed to date eight dune Systems named as Systems I to VII plus an additional CS, which is a laterally equivalent to part of S IV, V and VI. The proposed ages are: System I, age 11.1 38 to 9.5 ky BP, perhaps extending to 8.5 ky BP. System II, 8.2 to 6.1 ky BP. System III, 5.9 to 2.6 ky BP. 39 System IV, 2.6 to 1.6 ky BP. System V, 1.6 to 1.3 ky BP. System VI, 1.2 to 0.7 ky BP. System VII, 0.7 to 40 0.15 ky BP. The age of the Complex System is 2.2 to 0.15 ky BP. Additionally, it was concluded that genesis of the somewhat-different Complex System (CS) was related to the increased accumulation space created by movements (sliding) along the Mazagón and Torre del Loro faults following major regional seismic activity., Ministerio de Economía y Competitividad (MINECO)/FEDER, OAP, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

We present a detailed snow avalanche susceptibility map at scale 1:20,000 of the Circo de Gredos in the Sierra de Gredos (Iberian Central System, Spain). This cirque-shaped landscape is one of the most popular spots for winter sports in the region. However, no snow avalanche activity assessment has been conducted to date. We have, therefore, produced a snow avalanche susceptibility map based on aerial and satellite imagery, newspaper reviews and field work, including avalanche features recognition and interviews with frequent backcountry users. We extracted the spatial distribution of necessary and enhancer factors for triggering slab, wet and loose snow avalanches from a digital elevation model. Finally, calculations to evaluate each snow avalanche type susceptibility were performed using a Geographical Information System. By combining our map collection, we concluded that most of the area in the Circo de Gredos is highly susceptible to snow avalanches, especially slab and wet snow types., Ministerio de Ciencia e Innovación (MICINN), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

© Author(s). This research has been carried out in the framework of the IN-TIME project, which is funded by the European Commission under the Horizon 2020 Marie Skłodowska-Curie actions Research and Innovation Staff Exchange (RISE; grant agreement no. 823934). The authors are thankful to the institutions and individual members who participated in the project. Through other research projects, the Spanish Government (Ministerio de Economía, Industria y Competitividad and Ministerio de Ciencia e Innovación) additionally supported Luis Vázquez (ESP2016-79135-R), Mariano Sastre (PCIN-2014-013-C07-04, PCIN-2016-080, CGL2016-78702- C2-2-R and PID2019-105306RB-I00) and JLVP (RTI2018-096465- B-I00, EDGECLOUD). José Luis Vázquez-Poletti was also supported by the Madrid Regional Government (project EDGEDATA, S2018/TCS-4499). We would like to thank the associate editor and two anonymous reviewers for their thoughtful comments and efforts towards improving our paper., Accurate predictions of expected radiation dose levels on Mars are often provided by specific radiation transport codes that have been adapted to space conditions. Unsurprisingly, several of the main space agencies and institutions involved in space research and technology tend to work with their own in-house radiation codes. We present the codes that are related to the simulation of the radiation on Mars' surface under different scenarios. All of these codes have similar fields of application, but they differ with respect to several aspects, including the energy range and types of projectiles considered as well as the models of nuclear reactions considered., Unión Europea. Horizonte 2020, Ministerio de Economía y Competitividad (MINECO)/Ministerio de Ciencia e Innovación (MICCIN), Comunidad de Madrid, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

Land-use decisions in relation to seismic-induced landslide hazard are usually made through the preparation of hazard maps. The rigid-block method is probably the most used for this purpose. Under this method, Newmark displacement is computed for each slope unit and this displacement is used as a guide for establishing categories of hazard. At present, most relations used for computing Newmark displacement are established from moderate-to-high magnitude earthquakes (Mw ≥ 6.5). This data article provides Newmark displacements computed from accelerograms recorded in the Betic Cordillera for low-to-moderate magnitude earthquakes (Mw = 3.5–6.3). Records come from the Spanish Strong Ground Motion database (Instituto Geográfico Nacional). Newmark displacements were computed focusing on yield accelerations frequently recorded in such scenarios (0.02, 0.03, 0.04, 0.05, 0.06, 0.08 and 0.10), although higher accelerations were also considered (0.125, 0.15, 0.20, 0.25 and 0.30 g's). These data are useful for the study of the hazard in seismic scenarios of low-to-moderate magnitude, very frequent in practice. These data have been used in the study by Delgado et al., Ministerio de Economía y Competitividad (MINECO)/FEDER, Junta de Andalucía, Universidad de Jaén, Universidad de Alicante, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Mining is essential to the human economy and has been conducted for millennia. In the past ~60 years, the scale of disturbance created by mining has grown larger in response to economic demands and technology capacity. However the scale of disturbance from mining is dwarfed by that of urban expansion and agriculture. Nevertheless, it is well recognised that mine sites have radically disturbed abiotic and biotic system components that, post-mining need to restore new land uses and ecosystem goods and services. In many cases, such aims demand a geomorphic integration with the surrounding undisturbed landscape. Erosional stability based on geomorphic principles is the first and most important part of the process. Without erosional stability, vegetation will be difficult to establish and maintain and soil and nutrients will be lost from the site. In this review we outline this process and methods by which a geomorphic and integrative landscape can be established. We also examine the issue of establishing a self-sustaining landscape that is similar to that of the prior undisturbed landscape. Here we argue that this is not possible in almost all situations, however the development of a new and ecologically successful, albeit different landscape is. The community needs to accept that mining, like agriculture, is essential to the modern economy and that a past landscape cannot be replaced with the same, but a new, functional and productive one can be developed. However, the ability to do this and ensure long-term ecological sustainability is questionable for many sites and considerable effort needs to be made to develop the technology to ensure that this will occur. We outline a way forward, based on geomorphic design and modelling., Ministerio de Educación, Cultura y Deporte, Comunidad de Madrid, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

The Alhama de Murcia Fault is one of the main active structures of the Eastern Betic Shear Zone (SE Spain), characterized by the presence, along its trace, of Neogene basins developed under Early to Late Miocene extensional tectonics. A dominant NNW‐SSE shortening direction is active from Late Miocene driven by the present‐day plate convergence. We present the structural analysis of the northeastern section of this fault, where reliable estimations of slip rates were unknown due to the lack of geomorphological evidence of recent activity. The recent tectonic evolution and reactivation of the northeastern section is closely related to the Fortuna basin development and tectonic inversion. We approach the structural analysis through the interpretation of seismic reflection profiles, well data, fieldwork and 3D geological modeling. We estimated a maximum long‐term slip‐rate of (0.32 +0.18/‐0.13) mm/yr in the Librilla sector (last 4.8‐7.6 Ma), based on cross‐section restorations and assuming current motion trends from GPS data. According to the results from the cross‐sections restored along the section and a vertical displacement analysis based on a 3D model, the slip‐rate distribution shows a decrease of activity toward the northeastern tip of the studied fault section. This supports a transference of deformation between the Alhama de Murcia Fault and the Carrascoy Fault, which seems to absorb part of the shortening during the Plio‐Quaternary, explaining the lower relief created by the activity of the northeastern section. The slip rates obtained have important implications in seismic hazard assessments and in the distribution of deformation along the region., Ministerio de Ciencia e Innovación (MICINN), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

The NW Iberian margin is a hyperextended continental margin, formed during the opening of the North Atlantic Ocean, where a subsequent partial tectonic inversion has undergone during the Alpine Orogeny. This succession of tectonic episodes determines the magnetic signature of the margin. The Spanish Exclusive Economic Zone Project has carried out seven one-month cruises between 2001 and 2009. To extend and densify the spatial coverage, we have used data from the World Digital Magnetic Anomaly Map. Here, we describe the methodology used for the acquisition and data processing of the magnetic field data. The use of diverse instrumentation, a non-complete external field’s cancelation, and the use of different magnetic core field models, contributed to the total error budget. To reduce it, we have used a leveling algorithm which minimizes all these contributions. Finally, a statistical analysis was applied using crossover residuals, showing a resolution better than 28 nT., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

La Palma is one of the youngest of the Canary Islands, and historically the most active. The recent activity and unrest in the archipelago, the moderate seismicity observed in 2017 and 2018 and the possibility of catastrophic landslides related to the Cumbre Vieja volcano have made it strongly advisable to ensure a realistic knowledge of the background surface deformation on the island. This will then allow any anomalous deformation related to potential volcanic unrest on the island to be detected by monitoring the surface deformation. We describe here the observation results obtained during the 2006–2010 period using geodetic techniques such as Global Navigation Satellite System (GNSS), Advanced Differential Synthetic Aperture Radar Interferometry (A-DInSAR) and microgravimetry. These results show that, although there are no significant associated variations in gravity, there is a clear surface deformation that is spatially and temporally variable. Our results are discussed from the point of view of the unrest and its implications for the definition of an operational geodetic monitoring system for the island, Ministerio de Ciencia e Innovación (MICINN), Consejo Superior de Investigaciones Científicas (CSIC), Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

La revisión de las dataciones disponibles en la bibliografía relacionadas con los megadeslizamientos de la isla de Tenerifeocurridos en el último millón de años, y las nuevas dataciones Ar/Ar realizadas por los autores para acotar la edad de losmismos, han permitido proponer las siguientes edades para los deslizamientos de Icod: ~170 ka; La Orotava: ~560, ~530 y~500(?) ka; Güímar: ~830 ka; y Micheque: 810-830 ka (Ferrer et al., 2020-este volumen). En esta publicación se presentan lasrelaciones entre las evidencias geológicas y geomorfológicas indicadoras de los procesos de inestabilidad de los flancos,observadas tanto en superficie como en el interior de galerías que atraviesan los rellenos de los valles, y las edades de losdeslizamientos. Se refuerza la hipótesis de la ocurrencia de varios deslizamientos de flanco superpuestos o solapados, espaciados en el tiempo, al menos, varias decenas de miles de años, descartándose la hipótesis de procesos únicos de rotura masiva e instantánea del flanco insular; así, en el caso del valle de La Orotava, se confirma una edad en torno a los 530ka para un gran deslizamiento, y la ocurrencia de otros hacia los 560 ka y 500 ka. Se estudia también la relación y causalidad entre el deslizamiento de Icod, el último ocurrido en Tenerife, y la gran erupción explosiva del final del ciclo Cañadas, cuestión controvertida, y se demuestra que la explosión fue consecuencia del deslizamiento, desencadenada por éste hace ~170 ka. Se presentan nuevas evidencias del deslizamiento de Micheque, y se aportan nuevos datos que indican una edad pliocena para el sustrato profundo de los deslizamientos de La Orotava y Micheque., The review on the ages available in the bibliography (1972-2019) related to the mega-landslides of the island of Tenerife in the last million years, and the new Ar/Ar ages we have obtained have allowed us to propose the following ages for thelandslides of: Icod: ~170 ka; La Orotava: ~560, ~530 y ~500(?) ka; Güímar: ~830 ka; and Micheque: 810-830 ka (Ferrer et al.,2020-this volume). The relationship between the ages of the landslides and the geological and geomorphological evidence that support the flank instability failure processes, based on field observations in outcrops and underground data -from thegalleries excavated through the filling of the landslide valley- are presented. The hypothesis of several overlapping flank landslides, with time intervals of at least several tens of thousands of years is proposed, ruling out the occurrence of single processes of massive and instantaneous failure of the insular flank; thus, in the case of the La Orotava valley, an age of around 530 ka is confirmed for a large landslide, as well as the occurrence of other landslides around 560 ka and 500 ka. The relationship and causality between the Icod landslide, the last one that occurred in Tenerife, and the great explosive eruption at the end of the Cañadas cycle, and not the opposite as some authors have suggested, has also been analyzed, concluding that the explosion was a consequence of the landslide, ~170 ka ago. New data and evidence for the Micheque landslide are shown, indicating a Pliocene age for the deep substrate of the La Orotava and Micheque landslides., Ministerio de Ciencia e Innovación (MICINN), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

En este trabajo se describe el hallazgo de un hidrolacolito en la Sierra de Guadarrama (Sistema Central). Su estudio se ha realizado mediante la caracterización morfológica y de la estructura interna, a través del empleo de Modelos Digitales del Terreno (MDT) obtenidos de datos LiDAR y varios perfiles geoeléctricos. Los resultados permiten establecer la génesis de esta estructura, de origen periglaciar, y la influencia de los procesos de ladera en su evolución. Los ciclos hielo-deshielo y las condiciones hidrogeológicas del entorno son los factores que controlan la evolución que presenta a lo largo del tiempo esta morfología. Estas estructuras muestran una extraordinaria sensibilidad ambiental, por lo que su monitorización resulta de gran interés para garantizar su preservación futura., This research describes the finding of a hydro-laccolith in the Sierra de Guadarrama (Central System). The study, based on the combination of Digital Terrain Models (DTM) and geoelectric data, allowed the characterization of the surface morphology and internal structure. The results allow establishing the genesis of this periglacial-related structure and the role played by slope processes in its evolution. Freeze-thawing cycles and hydrogeological conditions are responsible factors that control its evolution over time. Such type of structures show an extraordinary environmental sensitivity, thus their monitoring is of great interest to guarantee their further preservation., Ministerio de Economía y Competitividad (MINECO), Organismo Autónomo de Parques Nacionales (MAGRAMA), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

The Sobrado unit, within the upper part of the Órdenes Complex (NW Spain) represents an allochthonous tectonic slice of exhumed high-grade metamorphic rocks formed during a complex sequence of orogenic processes in the middle to lower crust. In order to constrain those processes, U–Pb geochronology and rare-earth element (REE) analyses of accessory minerals in migmatitic paragneiss (monazite, zircon) and mylonitic amphibolites (titanite) were conducted using laser ablation split stream inductively coupled plasma mass spectrometry (LASS-ICP-MS). The youngest metamorphic zircon age obtained coincides with a Middle Devonian concordia monazite age (∼380 Ma) and is interpreted to represent the minimum age of the Sobrado high-P granulite facies metamorphism that occurred during the early stages of the Variscan orogeny. Metamorphic titanite from the mylonitic amphibolites yield a Late Devonian age (∼365 Ma) and track the progressive exhumation of the Sobrado unit. In zircon, cathodoluminescence images and REE analyses allow two aliquots with different origins in the paragneiss to be distinguished. An Early Ordovician age (∼490 Ma) was obtained for metamorphic zircons, although with a large dispersion, related to the evolution of the rock. This age is considered to mark the onset of granulite facies metamorphism in the Sobrado unit under intermediate-P conditions, and related to intrusive magmatism and coeval burial in a magmatic arc setting. A maximum depositional age for the Sobrado unit is established in the late Cambrian (∼511 Ma). The zircon dataset also record several inherited populations. The youngest cogenetic set of zircons yields crystallization ages of 546 and 526 Ma which are thought to be related to the peri-Gondwanan magmatic arc. The additional presence of inherited zircons older than 1000 Ma is interpreted as suggesting a West African Craton provenance., Ministerio de Economía y Competitividad (MINECO), Ministerio de Ciencia e Innovación (MICINN), Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

Rock-socketed piles are foundational elements designed to transmit large concentrated loads to stronger materials located at greater depths. The rock-socket side shear resistance is commonly estimated using empirical criteria as a percentage of the rock or concrete uniaxial compressive strength. However, this approach neglects the influence of other important aspects, such as the roughness of the pile-socket interface. In this work, numerical discrete-element models of rock-socketed piles with different degrees of socket roughness are employed to estimate the influence of the socket roughness on the load-settlement response and on the side shear resistance. The numerical simulation results are compared with predictions obtained using empirical correlations based on load test results and proposed by other authors. Results indicate that the discrete-element method is suitable to reproduce rock-socket pile behavior considering socket roughness; they also suggest that sockets drilled with standard tools in soft to medium rock tend to be relatively smooth unless artificially roughened with special tools and that damage to the interface asperities becomes more relevant after socket settlement of about 1% of the socket diameter, especially for rougher piles., José Entrecanales Ibarra Foundation, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

The Bransfield Basin is a back-arc basin located in Western Antarctica between the South Shetland Islands and Antarctic Peninsula. Although the subduction of the Phoenix plate under the South Shetland block has ceased, extension continues through a combination of slab rollback and transtensional motions between the Scotia and Antarctic plates. This process has created a continental rift in the basin, interleaved with volcanic islands and seamounts, which may be near the transition from rifting to seafloor spreading. In the framework of the BRAVOSEIS project (2017–2020), we deployed a dense amphibious seismic network in the Bransfield Strait comprising 15 land stations and 24 ocean-bottom seismometers, as well as a network of 6 moored hydrophones; and acquired marine geophysics data including multibeam bathymetry, sub-bottom profiler, gravity & magnetics, multi-channel seismics, and seismic refraction data. The experiment has collected a unique, high quality, and multifaceted geophysical data set in the Central Bransfield Basin, with a special focus on Orca and Humpback seamounts. Preliminary results confirm that the Bransfield region has slab-related intermediate depth seismicity, with earthquake characteristics suggesting distributed extension across the rift. Gravity and magnetic highs delineate a segmented rift with along-axis variations that are consistent with increased accumulated strain to the northeast. Orca volcano shows evidences of an active caldera and magma accumulation at shallow depths, while Humpback volcano has evolved past the caldera stage and is currently dominated by rifting structures. These differences suggest that volcanic evolution is influenced by the position along the rift. Although a lot of analysis remains, these results provide useful constraints on the structure and dynamics of the Bransfield rift and associated volcanoes., Ministerio de Ciencia e Innovación (MICINN), National Science Foundation, Alfred Wegener Institute, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Lobate scarps are the topographic expression of the largest thrust faults observed on the surfaces of terrestrial planets and their study provides information on the mechanical characteristics of the lithosphere at the time of formation. Here we show the results of 3D modeling of Ogygis Rupes, located in Aonia Terra, which is one of the most topographically pronounced lobate scarps described in the cratered martian highlands. The observed relief of Ogygis Rupes has been modeled by a combination of Trishear and Fault Parallel Flow algorithms, providing a successful reproduction of the observed topography through a 3D modeling that includes the main thrust fault, forming the lobate scarp relief, and two subsidiary backthrusts. This recreation allows us to interpret Ogygis Rupes relief, modeling the fault propagation folding, and constraining fault parameters and their variations along strike. The detailed slip distribution along the three faults reflects a general decay from the center to the edges for each fault, with the maximum slip value (2850 m) located approximately at the center of the main fault. The fault surfaces obtained for the main thrust fault and the two backthrusts show listric geometries at depth. The decollement where the main fault roots is set at ∼17–18 km deep, related to a main rheological threshold that on Mars is interpreted to be the depth of the Brittle-Ductile Transition at the time of the lobate scarp formation (Late Noachian/Early Hesperian). The listric morphology of the main fault implies that the total slip associated with this thrust fault is transmitted from the decollement, being representative of the regional shortening associated with the lobate scarp formation. Otherwise, the modeled backthrusts are subsidiary listric faults rooting at shallower depths (2.3–5.6 km), probably indicating the presence of mechanical discontinuities in the brittle domain of the martian lithosphere., Ministerio de Ciencia e Innovación (MICINN), Santander-UCM, Ministerio de Economía y Competitividad (MINECO), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Newmark displacement estimation is generally computed using empirical models. These models are estimated from large datasets that mainly comprise moderate-to-high magnitude events (Mw > 6.0). In this work, we study the performance of several of these models to study moderate-to-low magnitude scenarios. For this purpose, data from the Betic Cordillera, S Spain, with magnitudes ranging from Mw 3.5 to 6.3, were used to compare with model predictions. The results show that errors in the estimates depend on the magnitude of events or on the yielding acceleration considered to estimate the displacement. The availability of an appropriate range of data (magnitude and yielding acceleration), when defining the regression model, may overcome the differences due to specific characteristics of the seismotectonic context of the area where data derives from. The results also show that performance of models including several ground motion predictors is better than those based on a single parameter, regardless of the combination these predictors. Furthermore, regression models with polynomial forms present a better performance than other functions based on the logarithm of these predictors. Finally, new specific models for the Betic Cordillera are proposed, especially suitable for low magnitude events (< 5.0) and low critical accelerations (< 0.1 g), based on simplified polynomial forms of models., Ministerio de Economía y Competitividad (MINECO)/FEDER, Junta de Andalucía, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

In depth knowledge of the thermal and rheological properties of the crust and mantle of Mars is fundamental for constraining the strength of its lithosphere, and thereby for the understanding its geodynamics, tectonics, and thermal evolution. In this context, an interesting debate on Martian crustal composition is ongoing. The presence of highly differentiated rocks at several locations, and their implications for the thermal state, structure, and evolution of the planet are not well understood. Here we systematically explore the effects of crust material properties (specifically thermal conductivity and density) on the thermal and mechanical structure of the Martian lithosphere. For this purpose, we analyze different key indicators of the thermal state, the strength and mechanical behavior of the lithosphere under a wide range of conditions. We do so by considering suitable parameters for both a nominally basaltic Martian crust and an end-member basaltic crust that would include a significant low density and high thermal conductivity component. We find that crust material properties have a strong control over the thermal state of the entire lithosphere, and thereby over the strength of the lithospheric mantle. Although a lower crustal density reduces the brittle strength, the colder geotherm due to a higher thermal conductivity leads to a stronger crust and lithospheric mantle, and therefore to a thicker lithosphere. It also leads to a stronger lithosphere as a whole in terms of total strength and effective elastic thickness, as a consequence of higher crust and mantle contributions. On the other hand, we also investigate the influence of the rheology of Mars' upper mantle on the total strength of its lithosphere. Water content has a large effect on the rheology of the upper mantle. A wet rheology implies a substantial reduction of the mantle contribution to the total strength and effective elastic thickness of the lithosphere, resulting in a significantly weaker l, Unión Europea. Horizonte 2020, Ministerio de Ciencia e Innovación (MICCIN)/FEDER, Universidad Complutense de Madrid/Banco de Santander, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Land-use planning in regard of earthquake-triggered landslides is usually implemented by means of the production of hazard maps. The well-known Newmark rigid block methodology is the most frequent used approach for this purpose. In this method, slope stability is evaluated by the estimation of the Newmark displacement, which is used to set different categories of hazard. This methodology presents limitations due to the difficulty of incorporating the variability of the used variables. For that reason, the logic-tree approach has been used in order to incorporate the epistemic uncertainties and compute probabilistic seismic-landslide hazard maps. However, the used weights in the logic-tree are usually set for each branch based on an expert judgement or subjective criteria. This article provide data obtained from the use of logic-tree methodology; this dataset is useful for deriving the unbiased weights to use in such methodology and in moderate-to-low magnitude scenarios. The data presented here are related to the article entitled “Obtaining suitable logic-tree weights for probabilistic earthquake-induced landslide hazard analyses” (Rodríguez-Peces et al., 2020), Ministerio de Economía y Competitividad (MINECO)/FEDER, Universidad Complutense de Madrid, Universidad de Alicante, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Abandoned mine wastes, containing high sulfide contents, are of particular concern because of the formation of acid mine drainage (AMD), becoming an active and harmful point source of potentially toxic elements (PTEs) to the environment. A detailed evaluation of the chemical and mineralogical composition of mining wastes is necessary to determine effective remediation actions. Due to the high amount of generated wastes as a result of mining and processing activities, the cost and time consumed for this characterization are limiting. Hence, efficient tools could be applied to predict the composition of these wastes and their spatial distribution. This study aims to determine the physico-chemical characterization of wastes from mining activities using geochemical and geophysical techniques. The obtained results, both geochemical and geophysical, allow us to locate areas with a high potential risk of contamination by As in an economic and simple way, and enable us to design detailed geochemical sampling campaigns. In addition, the fact that there are conductive fractures in depth suggests the possible circulation of contaminants through them as well as the preferential lines of circulation., Comunidad de Madrid, Depto. de Geodinámica, Estratigrafía y Paleontología, Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

We present a detailed geomorphological map of the landform assemblages originated by the two major paleoglaciers of the Sierra de Gredos mountain range in the Spanish Iberian Central System. Based on previous works, our map focused on the features formed by Gredos and Pinar paleoglaciers during the last glaciation and subsequent glacial events. Based on a remote sensing analysis and exhaustive field surveys, we identified with great accuracy the local distribution of glacial, periglacial, mass movement, structural, fluvial, and lacustrine features. We recognized three main glacial geomorphological formations representing: (i) the maximum glacial extension reached (peripheral deposits); (ii) the culmination of glacial conditions (principal moraines) and (iii) the local glacial withdrawal (internal deposits). Our map offers a renewed spatial framework on which to conduct higher-resolution glacial chronologies, especially of Late Glacial and Holocene glacial activity, providing key information for performing future paleoclimatic reconstructions of the northern hemisphere mid-latitudes., Ministerio de Economía, Comercio y Empresa (España), Universidad de Castilla La Mancha, Comisión Nacional de Investigación Científica y Tecnológica (Chile), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Uniaxial compressive strength (UCS) is one of the most important parameters in rock mechanics. Nevertheless, there are instances when it is not advisable to perform UCS standardised tests, because it is not possible to sample or because it is not feasible to obtain a significant enough set of results. Leeb hardness (LHD) is used for estimating UCS non-destructively and, currently, most research is focussed on improving its quality as UCS estimator by either increasing the number of samples or combining several sets of samples to obtain better fitting curves. This paper analyses if combining LHD with ultrasonic pulse velocity (UPV) improves UCS estimations obtained from LHD alone, analogously to what is already proven for SonReb methods. This is done considering how different lithology and, particularly, porosity impact on UCS estimations obtained from LHD. Results show that combining ultrasonic pulse velocity and Leeb hardness is an effective way to improve UCS estimations through portable and non-destructive techniques in non-porous polymineral rocks, in which Leeb hardness leads to relatively poor (R2 = 0.779) UCS estimations if used on its own., Comunidad de Madrid, Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

Hasta el presente, las edades de los grandes deslizamientos de flanco de la isla de Tenerife (islas Canarias) ocurridos en el último millón de años, se han estimado a partir de dataciones de depósitos volcánicos relacionados cronológicamente con los deslizamientos, siendo muy escasas las dataciones realizadas exprofeso para conocer sus edades. Con el propósito de acotarlas en lo posible, se han recopilado y revisado las dataciones disponibles válidas para delimitar las edades de los deslizamientos de Icod, La Orotava, Güímar y Micheque o Acentejo. Así mismo, se presentan nuevas dataciones Ar/Ar realizadas con el fin de ajustar en lo posible la edad de La Orotava, Güímar y Micheque. Por primera vez se publican dataciones en rocas de galerías en el valle de Güímar. Se han datado rocas a muro de los depósitos de los deslizamientos, donde hasta ahora se contaba con un solo dato publicado. Como resultado, se proponen las edades más representativas para los deslizamientos de Icod: ~170 ka; La Orotava: ~560, ~530 y ~500(?) ka; Güímar: ~830 ka; y Micheque: 810-830 ka. Para el valle de La Orotava, las nuevas dataciones permiten proponer la ocurrencia de varios deslizamientos superpuestos con intervalos de decenas de miles de años. Esto supone un nuevo planteamiento de los procesos de desmantelamiento de los flancos de grandes islas volcánicas, y un nuevo escenario para interpretar las dataciones. Pero también una mayor complejidad y recurrencia de los procesos de inestabilidad de los volcanes. Como complemento a los datos aquí aportados, formando la Parte II del presente trabajo, en Ferrer et al. (2020–este volumen) se presentan y discuten nuevos datos relacionados con la edad, desencadenamiento y desarrollo de los deslizamientos., The review on the ages available in the bibliography (1972-2019) related to the mega-landslides of the island of enerife in the last million years, and the new Ar/Ar ages we have obtained have allowed us to propose the following ages for the landslides of: Icod: ~170 ka; La Orotava: ~560, ~530 y ~500(?) ka; Güímar: ~830 ka; and Micheque: 810-830 ka (Ferrer et al., 2020-this volume). The relationship between the ages of the landslides and the geological and geomorphological evidence that support the flank instability failure processes, based on field observations in outcrops and underground data -from the galleries excavated through the filling of the landslide valley- are presented. The hypothesis of several overlapping flank landslides, with time intervals of at least several tens of thousands of years is proposed, ruling out the occurrence of single processes of massive and instantaneous failure of the insular flank; thus, in the case of the La Orotava valley, an age of around 530 ka is confirmed for a large landslide, as well as the occurrence of other landslides around 560 ka and 500 ka. The relationship and causality between the Icod landslide, the last one that occurred in Tenerife, and the great explosive eruption at the end of the Cañadas cycle, and not the opposite as some authors have suggested, has also been analyzed, concluding that the explosion was a consequence of the landslide, ~170 ka ago. New data and evidence for the Micheque landslide are shown, indicating a Pliocene age for the deep substrate of the La Orotava and Micheque landslides., Ministerio de Ciencia e Innovación (MICINN), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub