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© Springer. We thank the National Centers for Environmental Prediction and the European Centre for Medium-Range Weather Forecasts for the NCEP and ERA-40 reanalysis. We thank the Met Office Hadley Centre for the SST and sea ice data (HadISST) and the University of Maryland for the Simple Ocean Data Assimilation (SODA) reanalysis. We are indebted to the Max Plank Institute and the Deutsches Klimarechenzentrum (DKRZ) for the ECHAM5/MPIOM1 data. In particular, we thank Hans Winter, Hannes Thiemann, Helmuth Haak and Monika Esch for help with the MPIOM1 data. IG is supported by the research projects MULCLIVAR (CGL-2012- 38923-C02-01 - Spanish Ministry of Economy and Competitiveness) and PREFACE (EUFP7/2007–2013 grant agreement 603521). We thank Irene Polo, Marta Martín-Rey, Jorge López-Parages, Rubén Banderas, Tim Woollings and Christoph Raible for constructive remarks. We thank Gwendal Rivière and another anonymous reviewer for their pertinent comments and suggestions, which have contributed to improve this manuscript, Explosive cyclones are intense extra-tropical low pressure systems featuring large deepening rates. In the Euro-Atlantic sector, they are a major source of life-threatening weather impacts due to their associated strong wind gusts, heavy precipitation and storm surges. The wintertime variability of the North Atlantic cyclonic activity is primarily modulated by the North Atlantic Oscillation (NAO). In this study, we investigate the interannual and multi-decadal variability of explosive North Atlantic cyclones using track density data from two reanalysis datasets (NCEP and ERA-40) and a control simulation of an atmosphere/ocean coupled General Circulation Model (GCM-ECHAM5/MPIOM1). The leading interannual and multi-decadal modes of variability of explosive cyclone track density are characterized by a strengthening/weakening pattern between Newfoundland and Iceland, which is mainly modulated by the NAO at both timescales. However, the NAO control of interannual cyclone variability is not stationary in time and abruptly fluctuates during periods of 20-25 years long both in NCEP and ECHAM5/MPIOM1. These transitions are accompanied by structural changes in the leading mode of explosive cyclone variability, and by decreased/enhanced baroclinicity over the sub-polar/sub-tropical North Atlantic. The influence of the ocean is apparently important for both the occurrence and persistence of such anomalous periods. In the GCM, the Atlantic Meridional Overturning Circulation appears to influence the large-scale baroclinicity and explosive cyclone development over the North Atlantic. These results permit a better understanding of explosive cyclogenesis variability at different climatic timescales and might help to improve predictions of these hazardous events., Unión Europea. FP7, Ministerio de Economía y Competitividad (MINECO), Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

The El Salvador Fault Zone, firstly identified after the 13th February 2001 Mw 6.6 El Salvador earthquake, is a 150 km long, 20 km wide right-lateral strike-slip fault system. Ruptures along the ESFZ are thought to be responsible for most of the historical destructive earthquakes along the El Salvador Volcanic Arc, as well as for most of the current seismicity of the area. In this work, we focus on the geological setting of the fault zone by describing its geomorphology and structure, using field-based observations, digital terrain modelling, and aerial photograph interpretation with the aim at contributing to the understanding of the ESFZ slip behaviour. In particular, we address the ESFZ structure, kinematics and evolution with time. The ESFZ is a complex set of traces divided in major rupture segments characterized by different geometry, kinematics and geomorphic expressions. Natural fault exposures and paleoseismic trenches excavated along the fault show that the strike-slip deformation is distributed in several planes. Both geometry and kinematics of the fault zone are consistent with a transtensional strain regime. The estimated geological slip rate for the main fault segments by paleoseismic trenches and displaced geomorphic features implies a deficit in velocity of the fault compared to the available GPS velocities data. The high vertical scarps of some fault segments would require Quaternary slip rates not coherent neither with measured GPS velocities nor with slip rates obtained from paleoseismic analysis. This mismatch suggests a pre-existing graben structure that would be inherited from the previous regional roll back related extensional stage. We consider that the ESFZ is using this relict structure to grow up along it. As a result, we ropose a model for ESFZ development consistent with all these observations., La Zona de Falla de El Salvador (ZFES) es un sistema de falla de desgarre dextral de 150 km de longitud y 20 de anchura, que fue identificada por primera vez después del terremoto de Mw 6.6 de El Salvador de febrero de 2001. La mayoría de la sismicidad y de los terremotos históricos destructivos producidos en el arco volcánico salvadoreño han sido producidos por la ruptura de la ZFES. Este trabajo se centra en el marco geológico de la zona de falla describiendo su geomorfología y su estructura a través de observaciones de campo, del estudio de los modelos digitales del terreno y de la interpretación de las fotografías aéreas, con el objetivo de avanzar en el conocimiento del comportamiento de la ZFES. En concreto trataremos del estudio de la estructura, la cinemática y la evolución de la ZFES. La ZFES es un complejo sistema de fallas divididas en varios segmentos que se diferencian en la geometría, la cinemática y la expresión geomorfológica. En los afloramientos de la falla, así como en las trincheras paleosismicas excavadas se ha observado que la deformación de desgarre está distribuida en varios planos y tanto la geometría como la cinemática de la zona de falla indican que la ZFES está bajo un régimen de deformación transtensional. La tasa de deformación estimada para los principales segmentos a través del estudio paleosísmico y del análisis de indicadores geomorfológicos desplazados nos muestra un déficit de velocidad para la falla si lo comparamos con los datos obtenidos por GPS. Estos datos tampoco ayudan a explicar la existencia de grandes escarpes verticales que se observan en algunos segmentos de la falla, y que requerirían tasas de deformación muy elevadas. Esta discrepancia sugiere la existencia de una estructura de graben preexistente que puedo ser producida por el “roll-back” de la placa y que creó una fase extensional en el arco volcánico. En este trabajo consideramos que la ZFES está actualmente desarrollándose sobre la estructura extensional relicta, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

La región volcánica de Campo de Calatrava se ha interpretado como un proceso de volcanismo intraplaca desarrollado durante el Neógeno. Se han propuesto dos modelos geodinámicos contrapuestos para explicar el origen de este volcanismo: a) un proceso de rifting en un contexto extensional con un adelgazamiento localizado de corteza; b) un proceso flexural de la litosfera en un contexto compresivo débil sin adelgazamiento de corteza. El análisis de las anomalías gravimétricas de Bouguer y una modelización gravimétrica 2D a escala cortical contribuyen a discriminar entre los modelos geodinámicos propuestos para el origen del volcanismo. Los modelos gravimétricos se han constreñido en base a los estudios sísmicos profundos existentes en la zona y a la cartografía geológica regional. Los modelos gravimétricos descartan un adelgazamiento cortical, lo que cuestiona el modelo de rifting abortado y apoyan la hipótesis alternativa del proceso flexural de la litosfera en régimen compresivo débil como origen del volcanismo bético., The volcanic region of Campo de Calatrava has been interpreted as a process of intraplate volcanism developed during Neogene. Two opposed geodynamic models have been proposed to explain the origin of this volcanism: a) a rifting process in an extensional context with localized crustal thinning; b) a flexural lithospheric process in a weak compressive setting with no crustal thinning. The analysis of the Bouguer gravity anomalies and 2D crustal gravity modeling contribute to discriminate between the geodynamic models proposed for the origin of volcanism.The gravity models are constrained based on previous deep seismic sounding profiles and the regional geological mapping. Gravity models reject a crustal thinning, and then strongly questioning, the aborted rifting model. However, gravity models support a flexural lithospheric process in weak compressive regime as the origin of Betic volcanism., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Between 1957 and 1990, the PeñarroyaMining and Metallurgical Company (SMMPE) disposed about 60 million tonnes of tailings materials directly to the Mediterranean Sea. A substantial part of it (12.5 Mt) was dragged back by the sea currents progressively infilling the Portman Bay (Murcia, SE Spain), thus making the shoreline advance between 500 and 600 m seaward. The Roberto froth flotation plant processed mineral from manto-type deposits belonging to the Sierra de Cartagena-La Unión lead-zinc district. One of the mineral assemblages present in these deposits comprises greenalite, magnetite, sulfides, carbonates, and silica. Despite that magnetite recovery was undertaken by SMMPE between 1959 and 1967, we estimate that magnetite contained in the tailings hosts a substantial resource that could be as large as 2.3 Mt of iron ore. The ore contains magnetite ± hematite ± siderite. Tidal waves and sea currents led to gravimetric classification of the tailings material, with concentration of the dense iron oxides in the sandy fractions, eventually forming a coastal placer iron deposit. A major problem for magnetic separation is the intimate intergrowth between magnetite, hematite, and siderite. Besides, the sands contain large concentrations of Pb (0.27 %), Zn (0.72 %), and As (559 ppm)., Universidad de Murcia, Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

Interpreting the origin of carbonate breccias requires a detailed analysis because they may be the result of a wide variety of processes that produce similar features. This is the case of the Lower Cretaceous carbonate breccias of the Cameros Basin (previously interpreted as slump or collapse breccias), whose origin is interpreted after performing a detailed sedimentary, petrographic and tectonic study. The studied carbonate breccias consist of angular carbonate mudstone fragments floating in a matrix of calcite and quartz crystals. The breccias are interbedded with, and laterally associated to, alternating layers of carbonate mudstone and calcite and quartz pseudomorphs after gypsum, which show strong similirities to the breccia fragments and matrix, respectively, suggesting that the brecciated beds were originally composed of identical alternating carbonate mudstone and gypsum layers as the unbrecciated layers. The breccias are associated with frequently polyharmonic deformation structures, which are similarly oriented as the regional tectonic structures, indicating that they are related with the alpine contractional deformation of this area of the Cameros Basin. All these features suggest that the carbonate breccias were formed by tectonic deformation of alternating layers of carbonate mudstone and calcium sulphate, which have very different rheological behaviours. As a result, during tectonic deformation, sulphate flowed and carbonate layers were broken and displaced, producing a breccia of carbonate fragments within a sulphate groundmass. Afterwards, the sulphate groundmass was replaced by quartz and calcite, and the breccia acquired its final composition., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

A quantitative geomorphic analysis of the drainage system on Byers Peninsula, Livingston Island, has been carried out in order to study the relief evolution, glacial history and possible neotectonic influence on the largest ice-free area of the South Shetlands archipelago. Aerial photographs, SAR data from RADARSAT-2 satellite, field work, a digital elevation model and GIS spatial analysis have been used to identify, map and study the existing drainage basins. A series of morphometric parameters have been studied in 30 selected basins in order to characterize their shape as well as the drainage network. Results in morphometric parameters reveal elongation trends in the shape of basins and a limited hierarchical network, common of a youthful stage of landscape evolution models. Several morphometric indexes (hypsometric integral, hypsometric curves, SL index, transverse topographical drainage basin asymmetry-T-Factor) have been used to study possible controls on drainage development. Results have been discussed in relation to relief and drainage evolution linked to the spatial distribution of lithological units and structural framework. T-Factor shows an apparently disorganized pattern and absence of tectonic influence. However, there are local values of second order basin asymmetry directions and magnitudes, which could reflect a succession of master rills through time, related to the changes in water supply during the deglaciation history of Byers Peninsula. Hypsometric values and curves of basins are also mainly related to a young stage of landscape evolution. Analysis of hypsometric integrals together with T-Factor index has allowed us to establish a possible deglaciation model on Byers Peninsula, which successfully explains the results. Areas of different landscape evolution stage are linked in space and support the hypothesis of local glacial centers during the ice cover retreat process. SL index results do not show the same pattern in results, which could be du, Ministerio de Ciencia e Innovación (MICINN), Universidad Autónoma de Madrid, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

In the regions where few field neotectonics and paleoseismic studies have been performed (e.g., Central America), the interpretation of the seismic sources responsible for the historical (preinstrumental) catastrophic earthquakes lies almost entirely in the spatial distribution of damage interpreted from historical sources, mainly fragmentary written documents. The occurrence of catastrophic earthquakes affecting this region justifies the necessity of a deeper analysis of the geologic implications of the more significant historical earthquakes in light of the new insights. Recent advances in the identification and dating of surface‐rupture evidences along the central El Salvador volcanic arc led us to revisit some historical evidence of damage along this region and to combine geologic (paleoseismic) evidence with damage distribution. At least 11 destructive earthquakes have occurred in El Salvador since 1900 (White and Harlow, 1993; Fig. 1). These events caused more than 3000 deaths as a consequence of strong ground motions and/or subsequent landslides (Bommer et al. , 2002). The instrumental earthquake record shows that large ( M w>7) events occurred as reverse fault events along the interface between the subducted plate and the over‐riding continental plate or as normal‐faulting events within the subduction plate resulting from extensional forces generated by slab‐pull forces or by bending of the subduction plate (Alvarez‐Gomez, 2009). Onshore, instrumental earthquakes have been reported with moderate magnitudes ( M w 7.0 usually have been assigned to the subduction zone, whereas historical records with M w 7.0) associated with the rupture of the El Salvador fault zone …, Ministerio de Ciencia e Innovación (MICINN), New Zealand Ministry for Science and Innovation, Universidad Complutense de Madrid, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Ephemeral streams induce flash-flood events, which cause dramatic morphological changes and impacts on population, mainly because they are intermittent and less predictable. Human pressures on the basin modify load and discharge relationships, inducing dormant instability on the fluvial system that will manifest abruptly during flood events. The flash-flood response of two ephemeral streams affected by load supply modification due to land use changes is discussed in a combination of geomorphic and hydraulic approaches. During the Rivillas flash flood, intensive clearing on the basin led to high rates of sediment flowing into an artificially straightened and inefficient channel. The stream evolved from a sinuous single channel into a shallow braiding occupying the entire width of the valley floor. Misfits and unsteady channel conditions increased velocity, stream power and sediment entrainment capacity and considerably magnified flood damage. Resulting morphosedimentary features revealed a close relationship with the valley floor postflood hydraulic model, and pre-event awareness would have made it possible to predict risk-sensitive areas. In the second case, the Azohía stream, modelling of current pre-flood channel conditions make it possible to determine channel narrowing and entrenchment in the lower alluvial fan stretch. Abandonment of intensive agriculture, basin reforestation and urbanization diminish load contribution and trigger channel incision. This induces an increase in slope and velocity in the bankfull channel, producing renewed erosive energy and thus activating upstream propagation of incision and bank undermining. The absence of water-spreading dynamics on the alluvial fan in favour of confinement in a single channel produces an unstable dynamic in the system, also offering a false sense of stability, as long as no large magnitude floods occur. When modelling flood-prone areas and analysing hydraulic variables, it is important to detect possible anth, Ministerio de Economía y Competitividad (MINECO), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Phosphogypsum (PG) is a waste product of the phosphoric acid production process and contains, generally, high activity concentrations of uranium series radionuclides. This study is a contribution towards a risk assessment in areas affected by phosphate industry in SW Spain, integrating information from soil physicochemical characteristics, total and soluble potentially toxic elements (Zn, Pb, Cd, Cu, As and Fe), mineralogical composition and ecotoxicological evaluation. The applied bioassays confirmed the soil toxicity categorisation and then, it is highly recommended to complement the results from environmental chemistry with results from bioassays, in order to provide a more complete and relevant information on the bioavailability of contaminants and to characterise the risk of contaminated areas., Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

Mercury is covered by a megaregolith layer, which constitutes a poor thermally conducting layer that must have an influence on the thermal state and evolution of the planet, although most thermal modeling or heat flow studies have overlooked it. In this work we have calculated surface heat flows and subsurface temperatures from the depth of thrust faults associated with several prominent lobate scarps on Mercury, valid for the time of the formation of these scarps, by solving the heat equation and taking into account the insulating effects of a megaregolith layer. We conclude that megaregolith insulation could have been an important factor limiting heat loss and therefore interior cooling and contraction of Mercury. As mercurian megaregolith properties are not very well known, we also analyze the influence of these properties on the results, and discuss the consequences of imposing the condition that the total radioactive heat production must be lower than the total surface heat loss (this is, the Urey ratio, Ur, must be lower than 1) in a cooling and thermally contracting planet such as Mercury at the time of scarp emplacement. Our results show that satisfying the condition of Ur < 1 implies that the average abundances of heat-producing elements silicate layer is 0.4 times or less the average surface value, placing an upper bound on the bulk content of heat producing elements in Mercury’s interior., Ministerio de Economía y Competitividad (MINECO), European Social Fund (ESF), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Oblique convergence between the Caribbean plate's interior and the inactive Greater Antilles island arc has resultedin the collision and impingement of the thickened crust of theBeata ridge into southern Hispaniola Island. Deformation resulting from this convergence changes from a low-angle southward-verging thrust south of easternHispaniola, to collision and uplift in south-central Hispaniola, and to left-lateral transpression along theSouthern peninsula of Haiti in western Hispaniola. Using new swath bathymetry and a dense seismic reflectiongrid, we mapped the morphological, structural and sedimentological Elements of offshore southern Hispaniola.We have identified four morphotectonic provinces: the Dominican sub-basin, the Muertos margin, the Beataridge and the Haiti sub-basin. The lower slope of the Muertos margin is occupied by the active Muertos thrustbelt, which includes several active out-of-sequence thrust faults that, were they to rupture along their entirelength, could generate large-magnitude earthquakes. The interaction of the thrust beltwith the Beata ridge yieldsa huge recess and the imbricate system disappears. The upper slope of the Muertos margin shows hick slopedepositswhere the extensional tectonics and slumping processes predominate. The northern Beata ridge consistsof an asymmetrically uplifted and faulted block of oceanic crust. Our results suggest that the shallower structureand morphology of the northern Beata ridge can be mainly explained by a mechanism of extensional unloadingfrom the Upper Cretaceous onward that is still active residually along the summit of the ridge. The tectonicmodels for the northern Beata ridge involving active reverse strike–slip faults and transpression caused by theoblique convergence between the Beata ridge and the island arc are not supported by the structural interpretation.The eastern Bahoruco slope an old normal fault that acts as a passive tear fault accommodating the sharpalong-strike transition from low-an, Geological Survey Coastal and Marine Geology Program, Dirección General de Minería of the Dominican Republic, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

As a proxy for long-term lithospheric strength, the effective elastic thickness (Te) can be used to understand the relationship between lithospheric rheology and geodynamic evolution of complex tectonic settings. Here we present, for the first time, high-resolution maps of spatial variations of Te in Central America and surrounding regions from the analysis of the coherence between topography and Bouguer gravity anomaly using multitaper and wavelet methods. Regardless of the technical differences between the two methods, there is a good overall agreement in the spatial variations of re recovered from both methods. Although absolute re values can vary in both maps, the qualitative re structure and location of the main re gradients are very similar. The pattern of the re variations in Central America and surrounding regions agrees well with the tectonic provinces in the region, and it is closely related to major tectonic boundaries, where the Middle American and Lesser Antilles subduction zones are characterized by a band of high Te on the downgoing slab seaward of the trenches. These high re values are related to internal loads (and in the case of the southernmost tip of the Lesser Antilles subduction zone also associated with a large amount of sediments) and should be interpreted with caution. Finally, there is a relatively good correlation, despite some uncertainties, between surface heat flow and our re results for the study area. These results suggest that although this area is geologically complex, the thermal state of the lithosphere has profound influence on its strength, such that re is strongly governed by thermal structure., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

© 2014 American Geophysical Union. We would like to express our thanks to the paleomagnetic community for the effort of providing the archeo/ paleomagnetic data and the construction and updating of useful databases. We are very grateful for the review and helpful comments of Ron Shaar and a second anonymous referee. This work has been carried out within the Spanish Research Project CGL2011–24790 financed by the Spanish Ministry of Economy and Competitiveness. Financial support to this research was also given by the post doc positions ME-Fulbright CT-2010-0663 and ‘‘Assegno di Ricerca’’ INGV - Roma2 (FJPC) and Marie Curie Intra European Fellowship IEF-2012 (MGP). E. Thebault is acknowledged for providing the software of the Mehler functions of the R-SCHA2D, One of the main challenges of paleomagnetic research is to obtain high-resolution geomagnetic field intensity reconstructions. For the last millennia, these reconstructions are mostly based on archeomagnetic data. However, the quality of the intensity data available in the databases is very variable, and the high scatter observed in the records clearly suggests that some of them might not be reliable. In this work we investigate how the geomagnetic field intensity reconstructions and, hence, our present knowledge of the geomagnetic field in the past, are affected by the quality of the data selected for modeling the Earth’s magnetic ield. For this purpose we rank the European archeointensity data in four quality categories following widely accepted paleomagnetic criteria based on the methodology used during the laboratory treatment of the samples and on the number of specimens retained to calculate the mean intensities. Four geomagnetic field regional models have been implemented by applying the revised spherical cap harmonic analysis to these four groups of input data. Geomagnetic field models strongly depend on the used data set. The model built using all the available data (without any preselection) appears to be the less accurate, indicating some internal inconsistencies of the data set. In addition, some features of this model are clearly dominated by the less reliable archeointensity data, suggesting that such features might not reflect real variations of the past geomagnetic field. On the contrary, the regional model built on selected high-quality intensity data shows a very consistent intensity pattern at the European scale, confirming that the main intensity changes observed in Europe in the recent history of the geomagnetic field occurred at the continental scale., Spanish Ministry of Economy and Competitiveness, Marie Curie Intra European Fellowship IEF-2012 (MGP), Roma2 (FJPC), Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

Los Sistemas de Información Geográfica (SIG) son una herramienta cada día más indispensable en el campo de la Geología. Para demostrar su potencial, se ha realizado un análisis espacial tridimensional en ArcGIS 10.0 a partir de redes irregulares de triángulos (TIN) formados por las topografías previa y posterior a la erupción del año 1971 del volcán Teneguía (La Palma). La finalidad del artículo es calcular el volumen eruptivo en superficie, discutir las medidas llevadas a cabo en el estudio de la erupción en 1974, y tratar de conseguir un resultado volumétrico más exacto., Geographic Information Systems (GIS) are becoming day to day an essential tool in the field of Geology. To show its potential, we have used a three-dimensional spatial analysis in ArcGIS 10.0 from triangulated irregular networks (TIN) formed by topographies for the volcano Teneguía (La Palma, Canary Islands) before and after its eruption in 1971. The purpose of the study is to calculate the surface eruptive volume, discuss the measures carried out after the eruption in 1974, and try to get a more accurate volumetric result., Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

The island of Boa Vista is one of the oceanic islands with the largest amount of felsic rocks reported in the world (50% of the total outcropping igneous rocks of Boa Vista). The felsic rocks are trachytes and phonolites generated within the second main stage of the volcanic activity that lasted about four million years. Three consecutive felsic episodes are distinguished: the first occurred between 14.5Ma and 13.5Ma, the second between 13.6 Ma and 12.0 Ma, and the third and last between 12.0 Ma and 10.4Ma. Their geochemical composition reveals the presence of crystal fractionation processeswith participation of feldspars andamphibole aswell as different accessory phases involved in each episode. The Boa Vista felsic cone-sheet swarm, the youngest third episode, is formed by several hundreds of peralkaline ne-phonolitic sheets distributedwithin a circular surface about 11 kmin radius. The cone-sheets conforma single general pattern characterized by a decreasing dip outward the structure, together with a constant dip of each individual sheet. The average inclination of sheets is around 40° in the sectors next to the centre of the structure whereas it is only about 30° next to its periphery. The magmatic focus of the sheets is located over 3 km deep almost coinciding with the convergence centre of a contemporary basic radial dike swarm., Comunidad de Madrid, Universidad Complutense de Madrid, Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

La versión registrada de este artículo, publicado por primera vez en Contributions to mineralogy and petrology, está disponible en línea en el sitio web del editor: http://dx.doi.org/10.1007/s00410-014-0987-5, Blueschist facies terranes in the Variscan Ibero-Armorican Arc are restricted to scarce and relatively smallareas. One of these examples is the Cea´n Unit, which is the westernmost exposure of the middle allochthonous sheet of the Variscan belt in the Malpica–Tui Complex (NW Iberian Massif). The Cea´n Unit is a highly condensed metamorphic succession with a lower part in the blueschist facies and an upper part without HP relicts. It comprises variable proportions of glaucophane–chloritoid-bearing metapelites and mafic rocks with abundant well-preserved pseudomorphs after euhedral lawsonite. Both lithologies show systematic changes in texture and mineral composition that are spatially related depending on deformation. The metamorphic evolution of the metabasic rocks has been constrained in the P–T space through pseudosection approach and is characterised by H2O-undersaturated prograde evolution induced by the crystallisation of lawsonite. Peak conditions in the blueschist/LT-eclogite facies have been constrained at ca. 2.2 GPa and 560 ºC. Exhumationrelated metamorphism is characterised by a nearly isothermal decompression from the lawsonite-bearing fields to fields with stable albite at P & 1 GPa. This lead to the pseudomorphism of lawsonite in the early-decompression stages, and a subsequent amphibolite–greenschist facies overprint at P\0.8 GPa and T & 440–480 ºC. The preservation of the lawsonite crystal shape despite complete retrogression indicates that pseudomorphism occurred as a static process and that particular levels of the blueschist host rock were not affected by penetrative deformation during exhumation. 40Ar/39Ar step heating of phengitic muscovite from the pelitic schists interbedded with the lawsonite pseudomorph-bearing metabasic rocks yield plateau ages of ca. 363 ± 2 and 354 ± 1 Ma. The older age is interpreted as the age of the peak blueschist facies metamorphism. The age of 355 Ma is interpreted as a cooling age and is inferred to represent some, Ministerio de Economía y Competitividad (MINECO), Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

The El Salvador Fault Zone (ESFZ) is an active, c. 150 km long and 20 km wide segmented, dextral strike-slip fault zone within the El Salvador Volcanic Arc striking N90-100E. Although several studies have investigated the surface expression of the ESFZ, little is known about its structure at depth and its kinematic evolution. Our analysis of structural field data, remote sensing images and orphometric indices reveals a trenchward migration of the volcanic arc and furthermore suggests that not all structures within the ESFZ can be explained within the current tectonic context, but require a phase of extension or an extensional component of deformation at some stage in the evolution of the ESFZ. Such an extension and trenchward migration of the volcanic arc could be related to subduction roll-back of the Cocos Plate beneath the Chortis Block in Mio-Pliocene times. Such a possible evolution leads to open questions that we address in our research: Is the ESFZ a neo-formed fault zone, i.e. did it form during one phase of strike-slip or transtensional deformation, or do the structures in the ESFZ reflect a two-phase evolution, i.e. an early phase of extension overprinted by a later phase of strike-slip or transtension? Did subduction roll-back occur beneath El Salvador? We carried out analogue model experiments to test whether or not an early phase of extension is required to form the present-day fault pattern in the ESFZ. Analogue modeling is an effective tool in testing various hypotheses, as it allows the experimenter to control specific parameters and to test their influence on the resulting structures. Our experiments suggest that a two-phase tectonic evolution best explains the ESFZ: an early pure extensional phase linked to a segmented volcanic arc is necessary to form the main structures of the ESFZ and can explain the shallow geometry of the fault zone. This extensional phase is followed by a strike-slip dominated regime, which results in inter-segment areas with, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

In this work we analyze the tectonic setting of the recent damaging seismic series occurred in the Internal Zones of the eastern Betic Cordillera (SE Spain) and surrounding areas, the tectonic region where took place the 11th May 2011 Mw 5.2 Lorca earthquake. We revisit and make a synthesis of the seven largest and damaging seismic series occurred from 1984 to 2011. We analyze their seismotectonic setting, and their geological sources under the light of recent advances in the knowledge on active faults, neotectonics, seismotectonics and stress regime, with special attention focused on the Lorca Earthquake. These seismic series are characterized by two types of focal mechanisms, produced mainly by two sets of active faults, NNW–SSE to NNE–SSW small (no larger than 20–30 km) extensional faults with some strike slip component, and E–W to NE–SW large strike slip faults (more than 50 km long) with some compressional component (oblique slip faults). The normal fault earthquakes related to the smaller faults are dominant in the interior of large crustal tectonic blocks that are bounded by the large E–W to NE–SW strike-slip faults. The strike slip earthquakes are associated to the reactivation of segments or intersegment regions of the large E–W to NE–SW faults bounding those crustal tectonic blocks. Most of the seismic series studied in this work can be interpreted as part of the background seismicity that occurs within the crustal blocks that are strained under a transpressional regime driven by the major strike slip shear corridors bounding the blocks. The seismotectonic analysis and the phenomenology of the studied series indicate that it is usual the occurrence of damaging compound earthquakes of M ∼ 5.0 associated with triggering processes driven by coseismic stress transfer. These processes mainly occur in the seismic series generated by NNW–SSE to NNE–SSW faults. These mechanical interaction processes may induce a higher frequency of occurrence of this kind of earth, Ministerio de Ciencia e Innovación (MICINN), Universidad Complutense de Madrid, Consejo de Seguridad Nuclear, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

The Cantabrian Zone of NW Iberia preserves a voluminous, almost continuous, sedimentary sequence that ranges from Neoproterozoic to Early Permian in age. Its tectonic setting is controversial and recent hypotheses include (i) passive margin deposition along the northern margin of Gondwana or (ii) an active continental margin or (iii) a drifting ribbon continent. In this paper we present detrital zircon U–Pb laser ablation age data from 13 samples taken in detrital rocks from the Cantabrian Zone sequence ranging from Early Silurian to Early Permian in depositional age. The obtained results, together with previously published detrital zircon ages from Ediacaran– Ordovician strata, allow a comprehensive analysis of changing provenance through time. Collectively, these data indicate that this portion of Iberia was part of the passive margin of Gondwana at least from Ordovician to Late Devonian times. Zircon populations in all samples show strong similarities with the Sahara Craton and with zircons found in Libya, suggesting that NW Iberia occupied a paleoposition close to those regions of present-day northern Africa during this time interval. Changes in provenance in the Late Devonian are attributed to the onset of the collision between Gondwana and Laurussia. Additionally, the Middle Carboniferous to Permian samples record populations consistent with the recycling of older sedimentary sequences and exhumation of the igneous rocks formed before and during the Variscan orogeny. Late-Devonian to Permian samples yield zircon populations that reflect topographic changes produced during the Variscan orogeny and development of the lithospheric scale oroclinal buckling., Ministerio de Ciencia e Innovación (MICINN), Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

Received: 19/05/2011 / Accepted: 12/04/2013., Pliocene – Pleistocene lava flows, mainly of dacitic composition, are exposed in the Sierra de las Cruces (SC) volcanic range within the Mexican Volcanic Belt (MVB). SC volcanic rocks are porphyritic, generally containing an assemblage of plagioclase + amphibole + orthopyroxene ± clinopyroxene ± quartz ± Fe-Ti oxides. Most of them exhibit diverse mineralogical and geochemical features that attest a magma mixing and mingling processes with concomitant fractional crystallization in which a small volume of hot andesite magma injects into dacitic magma. Both rock types are probably derived from partial melting of continental crust at different levels. The evidences of magma mixing and mingling include: (a) normal and sieved plagioclases in the same sample, rounded and embayed crystals, and armoured rims over the dissolved crystal surfaces; (b) subrounded, vesicular magmatic enclaves, ranging from a few millimeters to ~20 centimeters in size, with plagioclase + orthopyroxene + amphibole + quartz ± olivine ± Fe-Ti-oxides assemblage; (c) mineral chemistry evidence such as crystals with reaction rims or heterogeneous plagioclase compositions (inverse and oscillatory zoning or normally and inversely zoned crystals) in the same sample; and (d) elemental geochemical variations and trace-element ratio more akin to magma mixing and to some extent diffusion process. These andesitic enclaves could be considered as portions of the intermediate magma that did not mix completely (mingling) with the felsic host lavas, confirming the major role of magma mixing and mingling processes in the overall evolution of the MVB., En la Sierra de las Cruces (SC), Cinturón Volcánico Mexicano (CVM), se encuentran expuestos flujos de lava, principalmente de composición dacítica, del Plioceno-Pleistoceno. Las rocas volcánicas de la SC son de textura porfirítica, conteniendo plagioclasa + anfibol + ortopiroxeno ± clinopiroxeno ± cuarzo ± óxidos de Fe-Ti. La mayor parte de ellas exhiben diversas características que indican un proceso de mezcla incompleta de magmas, con una cristalización fraccionada concomitante, en la que un pequeño volumen de un magma andesítico caliente es inyectado a un magma dacítico. Es probable que ambos tipos de roca se hayan generado por fusión parcial a diferentes niveles de la corteza continental. Las evidencias de la mezcla incompleta de magmas incluyen: (a) plagioclasas con texturas normal y anubarrada en la misma muestra, cristales redondeados y corroídos, y bordes de reacción en superficies de cristal disueltas; (b) enclaves magmáticos subredondeados y vesiculares, que ocurren en dimensiones de un pocos milímetros a ~20 centímetros de diámetro, con plagioclasa + ortopiroxeno + anfíbol + cuarzo ± olivino ± óxidos de Fe-Ti; (c) química de minerales, que incluye cristales con bordes de reacción o plagioclasas de composición heterogénea (zonación inversa y oscilatoria o cristales con zonación normal e inversa) en la misma muestra; y (d) variaciones geoquímicas de elementos y relaciones de elementos traza explicables por una mezcla de magmas y por un proceso de difusión. Los enclaves andesíticos podrían considerarse como porciones de magma intermedio que no se mezcló con los líquidos dacíticos receptores, lo que confirma la importancia de los procesos de mezcla incompleta de magmas en la evolución magmática del CVM., Universidad Autónoma de Nuevo León, Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

Las nuevas tecnologías nos brindan multitud de plataformas innovadoras para hacer del aprendizaje un proceso entretenido. En los últimos años, el videojuego ha ido ganando adeptos en la comunidad docente gracias a su carácter interactivo y su capacidad de inmersión. El videojuego es especialmente útil como herramienta para la consolidación de conocimientos cuando se concibe como simulador de una situación potencialmente real, ya que permite que el alumno empatice con las necesidades de los personajes y se implique directamente en la resolución de sus problemas. Este artículo tiene por objeto presentar una experiencia de clase realizada con cuarenta y tres alumnos de cuarto curso de Grado en Geología de la Universidad Complutense de Madrid. Se presta especial atención a la fase de elaboración del videojuego, así como a un proceso bidireccional de evaluación en el que los estudiantes tienen oportunidad de valorar su grado de satisfacción con el videojuego como actividad didáctica. Esta experiencia pone de manifiesto el valor de los videojuegos como herramienta didáctica en la enseñanza universitaria, ya que los resultados muestran un grado de aprovechamiento elevado y una acogida positiva por parte de los estudiantes., New technologies allow for the development of attractive learning interfaces. Video games are gradually gaining recognition among teachers due to their interactive nature. In particular, video games are useful tools to consolidate concepts. This is especially true of games that simulate real-life situations, largely because students empathise with the game’s characters and find it easy to get involved. This paper presents an experiment carried out with forty-three undergraduate Geology students from the Universidad Complutense de Madrid, Spain. Emphasis is placed on the development and evaluation processes, showcasing the results of a two-way evaluation that highlights student satisfaction., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

En la última década España ha aumentado la Lista Ramsar de humedales con algo más de una veintena de nuevas zonas, tres de las cuales constituyen las primeras lagunas de origen glaciar en España: El Parque Nacional de Aigüestortes i Estany de Sant Maurici, los Humedales de la Sierra de Urbión y los Humedales del Macizo de Peñalara. En el año 2012 un equipo del IGME inició el estudio de estos tres humedales con el objetivo de caracterizarlos hidrogeológicamente. Para ello se procedió a analizar las características físicas, geológicas, hidrogeológicas e hidroquímicas de cada uno de estos humedales, primero a partir de referencias existentes en la literatura científica y después, mediante una campaña de campo realizada en julio de 2012. Los resultados ponen de manifiesto que, en contra de lo que se pensaba, existen indicios de una posible dependencia de los tres humedales de las aguas subterráneas., The number of wetlands declared to be of international importance has increased by 24 in Spain in the last decade. Spain currently has 74 wetlands included in the Ramsar list. Among these are the first examples of high altitude wetlands (that is to say, higher than 1500 meters) and of glacial origin: Aigüestortes i Estany de Sant Maurici, Humedales de la Sierra de Urbión and Humedales del Macizo de Peñalara. The first two are to be found in the Ebro Hydrographic Basin and the third in that of the Tajo. The paper analyses the physical, geological, hydrogeological and hydrochemical characteristics of the three selected wetlands in each of the said sites: Estany de Sant Maurici, Laguna de Urbión and Laguna Grande de Peñalara. A literature study has been carried out supplemented by a water sample campaign in July 2012. The main contribution of this study is the examination of various hydrogeological aspects of these wetlands, which have not been examined in the past, possibly because it was thought that they had no relationship with groundwater. The three wetlands have clearly differentiated hydrogeological features. Only one of the three, Estany de Sant Maurici, is located within the area of a groundwater body, known as the Macizo Axial Pirenaico, made up of a fractured and compartmented carbonated system on which rest moraine deposits from the bottom of the valley which makes up the lake’s basin. However, this does not mean that there may not exist small local aquifers in areas classified as impermeable or of low permeability. This may be the case of the Laguna de Urbión, which is over a glacial moraine which rests on Cretaceous sandstones and marls, as well as the Laguna Grande de Peñalara in which the fractures and cracks of the orthogneisses on which it rests, along with the development of the processes of meteorization on their surfaces, may encourage the development of local aquifers responsible for the storing of melt water in the summer months and the maintenan, Instituto Geológico y Minero de España, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Ground subsidence is a critical problem in populated areas, which requires attention and routine monitoring. Specifically, subsidence related to the exploitation of aquifer systems is of particular interest in terms of risk for the possible damage to buildings and availability of water resources. We propose to realise a survey of the aquifer systems near the city of Lorca, southern Spain, using Synthetic Aperture Radar Interferometry (InSAR) with a light method necessitating a small number of interferograms rather than analysing hundreds of radar images. We computed nine interferograms with good coherence over the years 2004 and 2005. We analysed them by a two-step filtering process in order to characterise the atmospheric contribution and the ground deformation. We are then able to identify two deforming areas and quantify subsidence rates at 0.20 ± 0.02 mm/day south of Lorca and southeast to the city of Alhama de Murcia with the same efficiency as the studies using sophisticated InSAR methods. Using continuous records of water levels in boreholes, we deduced a mean storage coefficient (Sk) at 4.1 × 10− 3 which is very close to the previous published values, and coincides in this case to an inelastic deformation mode of all the system. With this value, we determine the groundwater level variations from the measurements of the ground subsidence., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Al Este de la ciudad de Madrid, en el valle del río Jarama y entre Mejorada del Campo y Velilla de San Antonio se han estudiado las propiedades paleomagnéticas de una secuencia de terrazas comprendidas entre El Rasillo y Altos de la Mejorada, a lo largo de la autopista M-203 de reciente construcción. La cartografía geomorfológica realizada permitió separar además de la llanura aluvial a +4-5 m, terrazas a +20 m, +30-35 m, +60-65 m, +85-90 m, +105-110 m y +125-130 m. De ellas se muestrearon 5 niveles, a excepción de la de +20 m, en taludes frescos de la autovía que permiten situar a las terrazas con altitudes relativas igual o mayores a +60-65 m en el Chron Matuyama, mientras que las terrazas a +20 m y +30-35 m pertenecerían al Chron Brunhes (< 0.780 Ma). Dataciones por ESR en terrazas del valle del río Arlanzón en Burgos (Moreno et al., 2012), sugieren que en el valle del Jarama la inversión Matuyama-Brunhes podría establecerse entre el final de la sedimentación de la terraza a +60-65 m y el encajamiento de la terraza a +50-55 m subsiguiente, representada aguas arriba de Mejorada del Campo, en Marchamalo (Pérez-González, 1994)., To the east of Madrid city in the Jarama river valley and between Mejorada del Campo and Velilla de San Antonio, we have studied the paleomagnetic properties of the river terrace sequence in the M-203 highway, located between El Rasillo and Altos de La Mejorada. Over a new geomorphological mapping the alluvial plain at +4-5 m and terraces at +20 m, +30-35 m, +60-65 m, +85-90 m, +105-110 m and +125-130 m have been defined. Five terraces have been sampled with the exception of the terrace at +20 m, allowing to place those terraces at altitudes greater or equal to +60-65 m in the Matuyama Chron, while terraces at +20 m and +35 m belong to Brunhes Chron. ESR datings on terraces in the Arlanzón river valley in Burgos (Moreno et al., 2012), suggest that Matuyama-Brunhes inversion in the Jarama valley could be established between the end of the sedimentation of the +60-65 m terrace and the engagement of subsequent +50-55 m terrace, located upstream from Mejorada del Campo, in Marchamalo (Pérez-González, 1994)., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

El Salvador is the smallest and most densely populated country in Central America; its coast has an approximate length of 320 km, 29 municipalities and more than 700 000 inhabitants. In El Salvador there were 15 recorded tsunamis between 1859 and 2012, 3 of them causing damages and resulting in hundreds of victims. Hazard assessment is commonly based on propagation numerical models for earthquake-generated tsunamis and can be approached through both probabilistic and deterministic methods. A deterministic approximation has been applied in this study as it provides essential information for coastal planning and management. The objective of the research was twofold: on the one hand the characterization of the threat over the entire coast of El Salvador, and on the other the computation of flooding maps for the three main localities of the Salvadorian coast. For the latter we developed high-resolution flooding models. For the former, due to the extension of the coastal area, we computed maximum elevation maps, and from the elevation in the near shore we computed an estimation of the run-up and the flooded area using empirical relations.We have considered local sources located in the Middle America Trench, characterized seismotectonically, and distant sources in the rest of Pacific Basin, using historical and recent earthquakes and tsunamis. We used a hybrid finite differences–finite volumes numerical model in this work, based on the linear and non-linear shallow water equations, to simulate a total of 24 earthquake-generated tsunami scenarios. Our results show that at the western Salvadorian coast, run-up values higher than 5m are common, while in the eastern area, approximately from La Libertad to the Gulf of Fonseca, the run-up values are lower. The more exposed areas to flooding are the lowlands in the Lempa River delta and the Barra de Santiago Western Plains. The results of the empirical approximation used for the whole country are similar to the results obtained, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

La secuencia de El Cañizar de Villarquemado (NE Península Ibérica) constituye un registro excepcional que cubre los últimos ca. 130 000 años de historia ambiental. Los análisis multidisciplinares que se han realizado hasta el momento incluyen un análisis palinológico preliminar y otros indicadores sedimentológicos, como susceptibilidad magnética, análisis geoquímicos de fluorescencia de rayos X (XRF), mineralogía y contenido en carbono orgánico e inorgánico (TOC/TIC). El modelo cronológico se ha realizado combinando dataciones AMS 14C en los 20 m superiores de sedimento y OSL (Luminiscencia Óptica Estimulada) en los 54 m restantes. La secuencia sedimentaria está esencialmente formada por la alternancia de fases con mayor desarrollo de humedales y turberas, con otras de depósitos distales de abanicos aluviales y episodios de lago carbonatado. Los resultados obtenidos hasta el momento confirman que el registro del Cañizar de Villarquemado responde a unas condiciones relativamente húmedas durante un probable MIS6-MIS5, con variaciones en la vegetación regional (esencialmente dominada por Juniperus) que aparecen siempre muy determinadas por la continentalidad de la zona, y que resultan atípicas para lo esperable durante un episodio interglacial como el Eemiense. De todos modos, los márgenes de error adscritos al modelo de edad impiden ciertas precisiones y aseveraciones al respecto. Durante el MIS3 se registra el periodo más árido de toda la secuencia, como confirman los resultados sedimentológicos y los polínicos de algunos intervalos ya disponibles. Sin embargo el MIS2 presenta una gran variabilidad tanto a nivel local, como indican las distintas asociaciones de facies y la vegetación acuática, como a nivel regional, como se deduce de la cubierta vegetal general. El comienzo del Holoceno se registra de manera muy abrupta en cuanto a cambios paleohidrológicos, pero mostrando de nuevo cierta resiliencia de la vegetación, dominada esta vez por pinos y no por Juniperus co, El Cañizar de Villarquemado sequence (North-eastern Iberian Peninsula) stands as an exceptional palaeoenvironmental record for the last 130 000 years. The preliminary multidisciplinary study carried out so far include pollen and sedimentological analyses, comprising geochemical, X ray fluorescence (XRF), mineralogical, organic and inorganic content (TOC/TIC) analyses. The chronological model has been established combining AMS 14C on the first 20 m of sediment and OSL methods on the remaining 54 m to the bottom. The sedimentary sequence is essentially formed by alternating facies of peatbogs and wetlands with those of distal alluvial fan deposits and others of carbonate lake. The results currently obtained support relatively humid conditions at El Cañizar de Villarquemado during a likely MIS6-MIS5 period, as errors linked to the age model prevent us to guarantee precisely the period boundaries. Despite indications of humidity, the regional vegetation variations during the MIS6-MIS5 period, essentially represented by Juniperus, were constrained by the intense continentality of the area, resulting in unexpected pollen assemblages for an interglacial period as the Eemian. The most arid phase of the sequence is registered during the MIS3, as shown by the available sedimentological and palynological results, while the MIS2 presents greater local and regional variability as proved by the sedimentary facies and aquatics and the other pollen spectra, respectively. The Holocene presents an abrupt onset regarding palaeohydrology while terrestrial vegetation, dominated by pine instead than Juniperus as in the sequence's bottom, show a resilient response as these are well adapted communities to extreme continentality. The later development of both, evergreen and marcescent Quercus, together with the presence of pine woodland, indicate very different climatic conditions between the MIS5 and MIS1 interglacial periods. © Universidad de La Rioja., Gobierno de Aragón, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Received 22 April 2013 / Revised 3 July 2013 / Accepted 17 July 2013 / Available online 29 July 2013., Detailed Monte Carlo models of the interaction of impact cratering and volcanic resurfacing, which included the Beta-Atla-Themis (BAT) volcanic concentration, were used to test different planetary resurfacing histories. The results were compared with: (1) the randomness of the spatial distribution of craters, (2) the number of modified craters, (3) the number of dark-floored craters due to volcanic flooding, (4) the frequency-area distribution of volcanic units, (5) the frequency-size distribution of craters and modified craters, and (6) the spatial distribution of craters and modified craters with respect to the BAT anomaly. Two catastrophic and two equilibrium resurfacing models were tested. The two catastrophic models consisted of one with a drastic decay and the other with a moderate decay of volcanic activity following the catastrophic event. The two equilibrium models consisted of one with a gradual decay of volcanic activity at the end of the model and the other with a magmatic event followed by a gradual decay of volcanic activity. Both equilibrium models and the catastrophic model with moderate decay fail to reproduce the small reduction of the crater density in the BAT area. The model that best fits all the observations is a global catastrophic resurfacing event followed by a drastic decay of volcanic activity. Thus, a Venus global catastrophic resurfacing event erasing all previous craters with little post-resurfacing volcanism is supported by this study., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Este artículo contiene una revisión de la historia y contenido actual de un concepto, el de astenosfera, clave en las modernas Ciencias de la Tierra. Definido por Barrell en 1914, cuando Wegener diseñaba su primer ataque a la Tierra inmóvil, fue rescatado por los geofísicos revolucionarios de la década de 1960 sólo para ser secuestrado a continuación por algunos sismólogos y, por último, devuelto al centro del escenario en la versión actual de la tectónica de placas. Con los mejores datos geofísicos, la astenosfera se define hoy como todo el manto superior no litosférico. Los autores aprovechan esta revisión para actualizar otros conceptos recientes sobre el interior de la Tierra, como son el motor de las placas litosféricas o las avalanchas en el manto. Y destacan también las áreas más inciertas, como son los procesos en la interfase manto superior-manto inferior y las fuentes del calor interno de nuestro planeta., This paper aims to revise the history and present meaning of the asthenosphere concept, a keystone in modern Earth Sciences. Defined by Barrell in 1914, at a time when Alfred Wegener was outlining his first attack on the fixed Earth, it was rescued by the geophysicist-revolutionaries of the 60s, only to be kidnapped right afterward by some hurried seismologists, and at last brought back centre stage with the latest version of plate tectonics. The best geophysical data currently define the asthenosphere as the entire upper, non-lithospheric mantle. In addition to this historical account, the article also contains revisions of other important concepts regarding the Earth’s interior, such as the engine that propels the lithospheric plates or the avalanches that silently run through the deep mantle. It also explores some poorly-defined areas of the planet’s innards: the battlefield between the upper and lower mantle, and the still elusive heat sources that move everything down there., Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

Derechos de reproducción bajo licencia Creative Commons 3.0., The City of Granada is placed at the margin of a flat area known as the Granada Basin (Betic Cordillera, SE Spain) surrounded by mountains. The seismic activity in the Granada Basin is high, with a large number of earthquakes, all of them of moderate to low magnitude (mb ≤ 5.5). Historically, earthquakes in this area have produced important material damage and human casualties; however, it is hard to evaluate their magnitude. Seismicity has its origin mostly at depths between 5 and 17 km and the focal mechanisms indicate a present stress field dominated by a tensional tensor with an associated NE-SW extensional axis. The sedimentary cover of the Granada Basin is mostly coeval with the activity of faults that bound the basin, which have controlled the stratigraphic architecture. These faults are normal, mostly with a NW-SE orientation, and dipping towards the SW. Basinwards migration of the extensional front has exhumed the footwalls of older faults, uplifting the previous Tortonian sedimentary cover, which presently outcrops as emerged ranges at the margins of the basin. This work presents preliminary results of a paleoseismic study of the Granada Fault, an NW-SE active normal fault that produces a Plio-Quaternary throw of 300 m. According to these data, slip rate has been estimated in 0.38 mm/yr. Several paleosoils, Pleistocene in age, have been affected by this fault. These paleosoils were sampled and dated using the thermoluminiscence method to constrain these estimates. Three different seismic events can be recognized from the accumulative throw. The vertical slip per event ranges from 5 to 7 cm. Following empirical relationships, a moment magnitude between 5.9 and 6.0 can be preliminary assessed for these events., La ciudad de Granada está situada en el margen de un área llana rodeada de montañas conocida como la Cuenca de Granada (Cordillera Bética, SE España). La actividad sísmica en la Cuenca de Granada es alta, con un gran número de terremotos, todos ellos de moderada a baja magnitud (mb ≤ 5.5). Históricamente, los terremotos en este área han ocasionado importantes pérdidas materiales y de vidas humanas; sin embargo, es difícil de establecer su magnitud. La sismicidad se origina a profundidades de entre 5 y 17 km y los mecanismos focales indican un campo de esfuerzos actual dominado por un tensor extensional asociado a un eje de extensión NE-SO. El relleno sedimentario de la Cuenca de Granada es sincrónico con la actividad de las fallas que limitan la cuenca, las cuales han controlado la secuencia estratigráfica. Estas fallas son normales, la mayoría con una orientación NO-SE, y buzamientos hacia el SO. La migración hacia el interior de la cuenca del frente extensional ha exhumado los bloques de muro de las fallas más antiguas, elevando la cobertera sedimentaria Tortoniense previa, que actualmente afloran como sierras emergidas en los márgenes de la cuenca. Este trabajo presenta los resultados preliminares de un estudio paleosísmico de la Falla de Granada, una falla normal activa con orientación NO-SE que produce un salto Plio-Cuaternario de 300 m. Según estos datos, la tasa de deslizamiento se ha estimado en 0,38 mm/año. Varios paleosuelos, de edad Pleistoceno, han sido afectados por esta falla. Estos paleosuelos se muestrearon y dataron por el método de termoluminiscencia para precisar estas estimaciones. Se pueden reconocer tres eventos sísmicos a partir del salto acumulativo. El salto vertical por evento es de 5 a 7 cm. A través de relaciones empíricas, preliminarmente se ha establecido una magnitud momento entre 5.9 y 6.0 para estos eventos., Ministerio de Ciencia e Innovación (MICINN), Ministerio de Medio Ambiente, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

We investigate Lake Estanya's diatom and pollen records from the Late Glacial (LG) to the Early Holocene (EH), in order to compare limnological and vegetation responses to common climate forcing. The biotic changes recognized in this study largely agree with the hydrological evolution of the lake described previously for the same period. The diatom record shows high sensitivity to fluctuations in both lake level and salinity concentration as a consequence of climate shifts. In addition vegetation results indicate that the area could have played an important role as regional vegetation refuge. Shallow lake conditions during the Last Glacial Maximum (LGM) were punctuated by relatively deeper freshwaters between 19.3 and 18.6 cal kyr BP and at 18.0 cal kyr BP, as recorded by diatom shifts. A subsequent increasing aridity trend, coinciding with the Mystery Interval (MI), affected the diatom accumulation rates, which dropped to its minimum values between 17.2 and 14.7 cal kyr BP. Particularly dry and cold conditions during the LGM and MI are supported by the largest values of steppic pollen taxa of the whole sequence, which account for up to 40%. However, relatively high values of Betula during the Heinrich Event 1 suggest a plausible regional vegetation refuge. Abrupt cooling and warming episodes within the LG triggered remarkable ecological threshold crossings in the diatom communities, especially during the stadial/interstadial episodes. At this point, the vegetation reflects the onset of warm conditions during the Bølling/Allerød with the partial substitution of Betula by Marcescent and Evergreen Quercus, which probably indicates the arrival of temperate taxa to the area and the likely migration of birch to higher altitudes. The Younger Dryas Stadial shows a complex ecological response. Diatoms are very poorly preserved, but aquatic taxa reach their highest values. An increase in Marcescent Quercus during this cold stage lends further support to the hypothesis that t, Ministerio de Ciencia e Innovación (MICINN), Diputación General de Aragón, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Data from deep boreholes, seismic surveys, and surface geology are used to reconstruct the sedimentary infilling of the Cenozoic Madrid Basin. Eight main depositional sequences and seismic units are recognised. From the Paleogene, the latter four of these sedimentary sequences were deposited in a continental environment, under the influence of tectonic activity in the Central System, the Toledo Mountains, the Iberian Chain, and the Sierra de Altomira. The sedimentary infill shows an overall coarsening-upward trend from upper Cretaceous formations to syn-tectonic conglomerate deposits, followed by a fining-upward sequence and moderate reactivation of some faults during the late Miocene–Pliocene. The syn-tectonic sediments are Oligocene–early Miocene in age. The foredeep is oriented northeast–southwest and shows a sediment thickness of up to 3800 m in areas close to the Central System. Several types of tectonic structures are recognised, including imbricate thrust systems, thrust triangle zones, fault-propagation folds, back-thrust systems, and pop-up structures. The frontal thrusts were subjected to significant erosion, and late Miocene sediments onlap the anticlines of the onshore foreland. NW–SE-trending positive flower structures have been recognised in the eastern part of the basin. The total northwest–southeast shortening across the contact between the Madrid Basin and the Central System is approximately 5 km, of which 2–3 km occurred across the Southern Border Thrust. The simultaneous basement uplift of the Central System and the tectonic escape of the Sierra de Altomira have been interpreted as a consequence of constrictive deformation within the “Pyrenean” foreland of the Iberian microplate., Ministerio de Educación y Ciencia, Consolider Ingenio 2006, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Received: 28 Jan 2013 / Discussion started: 14 Mar 2013 / Revised: 14 Jun 2013 / Accepted: 20 Jul 2013 / Published: 29 Aug 2013., Soil loss and sediment transport in Mediterranean areas are driven by complex non-linear processes which have been only partially understood. Distributed models can be very helpful tools for understanding the catchment-scale phenomena which lead to soil erosion and sediment transport. In this study, a modelling approach is proposed to reproduce and evaluate erosion and sediment yield processes in a Mediterranean catchment (Rambla del Poyo, Valencia, Spain). Due to the lack of sediment transport records for model calibration and validation, a detailed description of the alluvial stratigraphy infilling a check dam that drains a 12.9 km2 sub-catchment was used as indirect information of sediment yield data. These dam infill sediments showed evidences of at least 15 depositional events (floods) over the time period 1990–2009. The TETIS model, a distributed conceptual hydrological and sediment model, was coupled to the Sediment Trap Efficiency for Small Ponds (STEP) model for reproducing reservoir retention, and it was calibrated and validated using the sedimentation volume estimated for the depositional units associated with discrete runoff events. The results show relatively low net erosion rates compared to other Mediterranean catchments (0.136Mgha−1 yr−1), probably due to the extensive outcrops of limestone bedrock, thin soils and rather homogeneous vegetation cover. The simulated sediment production and transport rates offer model satisfactory results, further supported by in-site palaeohydrological evidences and spatial validation using additional check dams, showing the great potential of the presented data assimilation methodology for the quantitative analysis of sediment dynamics in ungauged Mediterranean basins., Ministerio de Economía y Competitividad (España), Ministerio de Economía y Competitividad (España), Ministerio de Economía y Competitividad (España), Ministerio de Economía y Competitividad (España), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

The Cantabrian Zone of NWIberia preserves a voluminous, almost continuous, sedimentary sequence that ranges in age from Ediacaran to Early Permian. Its tectonic setting is controversial and recent hypotheses include (i) passive margin deposition along the northern margin of Gondwana, (ii) an active continental margin, or (iii) the margin of a drifting ribbon continent and (iv) a combination of the three aforementioned possibilities. In this paperwe present geochemical data from 21 samples taken in detrital rocks in the Cantabrian Zone from Ediacaran to Early Permian age. The results, together with previously published detrital zircon ages from these strata, allow a comprehensive analysis of changing tectonic scenarios and provenance through time. Collectively, these data indicate that this portion of Iberia was an active margin during the Ediacaran that evolved to become part of the passive margin of Gondwana at least from Ordovician to Late Devonian times. Changes in geochemistry, zircon age distribution and Sm/Nd isotopes during the Carboniferous are attributed to the far-field effects of the onset of the collision between Gondwana and Laurussia, and related processes such as recycling of older sedimentary sequences, as well as the involvement of the rocks formed during the Variscan orogeny and oroclinal buckling. Latest Carboniferous and Permian show a more juvenile Sm/Nd and higher values of illite cristallinity that may support the hypothesis of lithospheric foundering after oroclinal buckling., Ministerio de Economía y Competitividad (MINECO), Ministerio de Ciencia e Innovación (MICINN), UNESCO, Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

Estimates of lithospheric strength for Mercury, based on the depth of thrust faults associated with large lobate scarps (which were most probably formed previously to similar to 3 Ga) or on the effective elastic thickness of the lithosphere supporting a broad rise in the northern smooth plains (whose formation is poorly constrained, but posterior to 3.8 Ga), serve as a basis for the calculation of paleo-heat flows, referred to the time when these structures were formed. The so-obtained paleo-heat flows can give information on the Urey ratio (Ur), the ratio between the total radioactive heat production and the total surface heat loss. By imposing the condition Ur < 1 (corresponding to a cooling Mercury, consistent with the observed widespread contraction), we obtain an upper limit of 0.4 times the average surface value for the abundance of heat-producing elements in the outer solid shell of Mercury. We also find that if the formation of the northern rise occurred in a time posterior to 3 Ga, then in that time the Urey ratio was lower, and the cooling more intense, than when most of large lobate scarps were formed. Thus, because largest lobate scarps deform older terrains (suggesting more intense contraction early in the mercurian history), we conclude that the northern rise was formed previously to similar to 3 Ga. If the age of other smooth plains large wavelength deformations is similar, then tectonic activity in Mercury would have been limited in the last 3 billion of years., Ministerio de Economía y Competitividad (MINECO), European Social Fund (ESF), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

A pesar de la importancia e implicaciones de los riesgos asociados a la dinámica litoral en las zonas costeras, son escasos los trabajos centrados en su estudio y cartografía a escala regional, de manera sistemática e integrada. En este trabajo se presenta una metodología basada en el análisis detallado de los peligros naturales que pueden afectar al litoral: inundaciones, erosión costera, subida del nivel del mar, tsunamis, movimientos de ladera, etc., y en el estudio y cartografía de los factores implicados en su ocurrencia (geomorfología litoral, procesos litorales, sucesos históricos, actuaciones humanas…). Estos factores y peligros se evalúan e integran para la elaboración de un mapa final de susceptibilidad en el que se presenta la valoración tanto de cada peligro de forma individual, como del conjunto de los mismos. El sistema de representación cartográfica empleado, en franjas paralelas a la costa, facilita el reconocimiento e interpretación de las características del litoral estudiado y los peligros asociados. La metodología que se presenta ha sido aplicada a la zona litoral de la Región de Murcia, mostrándose de forma práctica su utilidad para el caso analizado y su posible aplicabilidad a otras regiones., Despite the importance and implications of coastal hazards, very few studies have been focused on their analysis and mapping on a regional scale in a systematic and integrated way. This article presents a methodology based on the detailed analysis of natural hazards affecting coastal zones: floods, erosion, sea level rise, tsunamis, landslides, etc., and the study and mapping of the factors involved (coastal geomorphology, coastal processes, historical events, human activities…). These factors and hazards are evaluated and integrated to prepare maps which include the assessments of each individual hazard and the overall ones. A mapping system in strips parallel to the coast is used, allowing the recognition and interpretation of the characteristics of the coast and the associated hazards. This methodology is applied to the coastal zone of Murcia, showing its usefulness for studying and mapping coastal hazards and its applicability to other regions., Instituto Geológico y Minero de España, Murcia (Comunidad Autónoma). Consejería de Obras Públicas y Ordenación del Territorio, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Heat flow is a very important parameter for constraining the thermal evolution of a planetary body. Several procedures for calculating heat flows for Mars from geophysical or geological proxies have been used, which are valid for the time when the structures used as indicators were formed. The more common procedures are based on estimates of lithospheric strength (the effective elastic thickness of the lithosphere or the depth to the brittle–ductile transition). On the other hand, several works by Kargel and co-workers have estimated martian heat flows from scaling the present-day terrestrial heat flow to Mars, but the so-obtained values are much higher than those deduced from lithospheric strength. In order to explain the discrepancy, a recent paper by Rodriguez et al. (Rodriguez, J.A.P., Kargel, J.S., Tanaka, K.L., Crown, D.A., Berman, D.C., Fairén, A.G., Baker, V.R., Furfaro, R., Candelaria, P., Sasaki, S. [2011]. Icarus 213, 150–194) criticized the heat flow calculations for ancient Mars presented by Ruiz et al. (Ruiz, J., Williams, J.-P., Dohm, J.M., Fernández, C., López, V. [2009]. Icarus 207, 631–637) and other studies calculating ancient martian heat flows from lithospheric strength estimates, and casted doubts on the validity of the results obtained by these works. Here however we demonstrate that the discrepancy is due to computational and conceptual errors made by Kargel and co-workers, and we conclude that the scaling from terrestrial heat flow values is not a valid procedure for estimating reliable heat flows for Mars, Ministerio de Economía y Competitividad (MINECO), European Social Fund (ESF), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

El deslizamiento de Bàlitx, situado en el escarpado litoral de la Serra de Tramuntana de Mallorca es un gran deslizamiento rocoso traslacional, cuya superficie de rotura aprovecha un plano de falla normal preexistente. La datación de estrías de calcita sobre el plano de falla con U/Th pone de manifiesto que el último movimiento de la falla está fuera del rango de datación de este método (> 400 ka). El volumen de material movilizado por el deslizamiento se estima en unos 700 millones de metros cúbicos, con un desplazamiento de unos 300 m hacia el NO. Se han identificado procesos activos de apertura de grietas de tracción, con desplazamientos y desplomes de grandes bloques de roca procedentes del escarpe principal del deslizamiento, proceso cuyo inicio coincide con un máximo transgresivo hace 83 ka (Pleistoceno superior), correspondiente al estadio isotópico 5a (OIS 5a), constatado como más cálido y húmedo que el actual. En los materiales deslizados se han identificado grietas con longitudes decamétricas y aperturas de hasta 50 m, cuya generación y apertura continua en la actualidad, y que parecen poner de manifiesto la ruptura del bloque deslizado en varias unidades que se desplazan a distintas velocidades. Se ha realizado un análisis retrospectivo de la estabilidad, considerando varios escenarios posibles relacionados con posiciones críticas del nivel del mar. Los resultados ponen de manifiesto condiciones de estabilidad en todos los casos, con factores de seguridad >1.3, lo que avala la hipótesis de un posible origen sísmico del deslizamiento. El estudio en condiciones dinámicas pone de manifiesto que el deslizamiento de Bàlitx pudo ser provocado por un posible terremoto de magnitud moderada a alta (Mw≥6.0), localizado en las inmediaciones del deslizamiento (10-30 km), probablemente en relación con alguna de las fallas activas de Mallorca, como la de Palma., The Bàlitx landslide, located on the steep coastal side of the Tramuntana range on the island of Mallorca, is a large translational rock landslide in which the failure surface coincides with the reactivation of an earlier normal fault. The dating of calcite striae on the fault plane with U/Th techniques reveals that the last movement was over 400 kyr ago, which falls outside of the range of this method. The volume of the landslide is estimated to be over 700 million cubic metres, with a north-westward displacement of 300 m. Active extensional cracks as well as block spreads have been identified along the main scarp, together with displacement and toppling of blocks, the beginning of which coincides with oxygen isotope stage OIS 5a (Late Pleistocene = 83 kyr), a wetter and warmer period than the present. Currently active decametre-long cracks up to 50 m, España. Plan Nacional de Investigación Científica y Desarrollo e Innovación Tecnológica, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

High resolution multiproxy data (pollen, sedimentology, geochemistry, chironomids and charcoal) from the Basa de la Mora (BSM) lake sequence (42° 32′ N, 0° 19′ E, 1914 m a.s.l.) show marked climate variability in the central southern Pyrenees throughout the Holocene. A robust age model based on 15 AMS radiocarbon dates underpins the first precise reconstruction of rapid climate changes during the Holocene from this area. During the Early Holocene, increased winter snowpack and high snowmelt during summer, as a consequence of high seasonality, led to higher lake levels, a chironomid community dominated by non-lacustrine taxa (Orthocladiinae) related to higher inlet streams, and a forested landscape with intense run-off processes in the watershed. From 9.8 to 8.1 cal ka BP, climate instability is inferred from rapid and intense forest shifts and high fluctuation in surface run-off. Shifts among conifers and mesophytes reveal at least four short-lived dry events at 9.7, 9.3, 8.8 and 8.3 cal ka BP. Between 8.1 and 5.7 cal ka BP a stable climate with higher precipitation favoured highest lake levels and forest expansion, with spread of mesophytes, withdrawal of conifers and intensification of fires, coinciding with the Holocene Climate Optimum. At 5.7 cal ka BP a major change leading to drier conditions contributed to a regional decline in mesophytes, expansion of pines and junipers, and a significant lake level drop. Despite drier conditions, fire activity dropped as consequence of biomass reduction. Two arid intervals occurred between 2.9 and 2.4 cal ka BP and at 1.2–0.7 cal ka BP (800–1300 AD). The latter coincides with the Medieval Climate Anomaly and is one of the most arid phases of the Holocene in BSM sequence. Anthropogenic disturbances were small until 700 AD, when human pressure over landscape intensified, with Olea cultivation in the lowlands and significant deforestation in highlands. Colder and unfavourable weather conditions during the second part of the Li, CICIYT, Gobierno de Aragón, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Well-constrained case studies of transient landscape responses are needed to improve our understanding of erosion processes associated with drainage captures. The Duero basin is an excellent location for such a study because the landscape is currently undergoing pronounced geomorphological changes resulting from the opening of a former closed drainage. The present-day continental interior basin (N50,000 km2) drains to the Atlantic Ocean via the Duero River, but during the Cenozoic the basin experienced a long endorheic period marked by the formation of evaporites. Currently, the entire continental interior is an area of relative tectonic quiescence, characterised by a relict low-relief upland topography (Meseta). Systematic variations in lithology and a well-constrained tectonic setting throughout the basin and adjacent areas allow for the comparison of channel morphology between the Cenozoic Duero basin and its western fringe. To explore the signal of transient geomorphic response to capture and opening of the former endorheic basin, the main channel and 24 tributaries were analysed in terms of their longitudinal profiles and the application of geomorphic indices (concavity index [Ci], valley floorwidth-to-height ratio [Vf], and stream-length gradient index [SL]). The analysis reveals two zones with distinctive morphologies: (1) an upper reach domain consisting of broad flat valleys and low-gradient streams where concave longitudinal profiles dominate and (2) a middle reach domain characterised by steep, deeply incised canyons where a convex long profile dominates marking a major kinckzone. The quantitative information on channel shapes and long profile geometries allows the interpretation of these patterns in terms of driving forces for fluvial landscape development. Large-scale morphometric analysis highlights the transient response of the entire basin to a capture-related base level lowering and illustrates the importance of drainage captures as potential intern, Ministerio de Educación y Ciencia (MEC), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

ALCUDIA is a 230 km long, vertical incidence deep seismic reflection transect acquired in spring 2007 across the southern Central Iberian Zone (part of the pre-Mesozoic Gondwana paleocontinent) of the Variscan Orogen of Spain. The carefully designed acquisition parameters resulted in a 20 s TWTT deep, 60–90 fold, high-resolution seismic reflection transect. The processed image shows a weakly reflective upper crust (the scarce reflectivity matching structures identified at surface), a thick, highly reflective and laminated lower crust, and a flat Moho located at 10 s TWTT (30 km depth). The transect can be divided into three segments with different structural styles in the lower crust. In the central segment, the lower crust is imaged by regular, horizontal and parallel reflectors, whereas in the northern and southern segments it displays oblique reflectors interpreted as an important thrust (north) and tectonic wedging involving the mantle (south). The ALCUDIA seismic image shows that in an intracontinental orogenic crust, far from the suture zones, the upper and lower crust may react differently to shortening in different sectors, which is taken as evidence for decoupling. The interpreted structures, as deduced from surface geology and the seismic image, show that deformation was distributed homogeneously in the upper crust, whereas it was concentrated in wedge/thrust structures at specific sectors in the lower crust. The seismic image also shows the location of late Variscan faults in spatial association with the lower crustal thickened areas., Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

The Quaternary Active Faults Database of Iberia (QAFI) is an initiative lead by the Institute of Geology and Mines of Spain (IGME) for building a public repository of scientific data regarding faults having documented activity during the last 2.59 Ma (Quaternary). QAFI also addresses a need to transfer geologic knowledge to practitioners of seismic hazard and risk in Iberia by identifying and characterizing seismogenic fault-sources. QAFI is populated by the information freely provided by more than 40 Earth science researchers, storing to date a total of 262 records. In this article we describe the development and evolution of the database, as well as its internal architecture. Additionally, a first global analysis of the data is provided with a special focus on length and slip-rate fault parameters. Finally, the database completeness and the internal consistency of the data are discussed. Even though QAFI v.2.0 is the most current resource for calculating fault-related seismic hazard in Iberia, the database is still incomplete and requires further review., La Base de Datos de Fallas Activas de Iberia (QAFI) es una iniciativa promovida por el Instituto Geológico y Minero de España (IGME) para construir un repositorio público de información científica sobre fallas con ac-tividad en los últimos 2,59 Ma (Cuaternario). Además, la QAFI persigue establecer una base sobre la que facilitar la transferencia de conocimiento geológico al ámbito tecnológico de la gestión del riesgo sísmico en Iberia, en particular en la identificación y caracterización de fuentes sismogénicastipo falla. La QAFI se ha construido a partir de la información proporcionada de modo altruista por más de 40 investigadores en ciencias de la Tierra conteniendo actualmente un total de de 262 registros. En este artículo se describe la concepción y evolución de la base de datos, y su arquitectura interna. Además, se ofrece un primer análisis global de los datos que contiene, con especial interés en parámetros tan importantes como la longitud y tasa de deslizamiento de las fallas. Finalmente se discuten dos temas cruciales en cualquier base de datos: su completitud y la homogeneidad de los datos. Se concluye que QAFI v.2.0, pese a ser la fuente más actualizada de información disponible en Iberia sobre peligrosidad sísmica de fallas concretas, dista aun de ser completa, por lo que nuevas revisiones y versiones deberán seguir llevándose a cabo en el futuro., Unión Europea. FP7, Ministerio de Ciencia e Innovación (MICINN), Consejo de Seguridad Nuclear (CSN), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Mercurian lobate scarp sare interpreted to be the surface expressions of thrust faults formed by planetary cooling and contraction, which deformed the crust downto the brittle–ductile transition (BDT) dep that the time of faulting. In this work we have used a for ward modeling procedure in order to analyze the relation be tweens carptopography and fault geometrie sand dep thsas sociated with a group of prominent lobate scarps (Santa Maria Rupes and twoun named scarps) located inthe Kuiper region of Mercury for which Earth-based radar altimetry is available. Also aback thrust associated with one of the lobate scarps has been included in this study. We have obtained best fits for depthsof faul ting between 30 and 39 km; the results are consistent with the previous results for o ther lobate scarps on Mercury. The so-derived fault depths have been used to calculate surface heat flows for the time of faulting, taking into account crustal heat source sand a heterogeneous surface temperature due to the variable in solation pattern. Deduced surface heat flow sare be tween 19 and 39m Wm-2 for the Kuiper region, and between 22 and 43 mWm-2 for Discovery Rupes. Both BDT depth sand heat flows are consistent with the predictions of thermal history models for the range of time relevant for scarp formation., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Dynamic content features, such as animations, videos or 3D representations are useful tools to explain dynamic geological processes. Modern technologies permit development of animations that are more illustrative and instructive than the classic static figures traditionally used in scientific papers. In addition, the use of supplemental files in traditional journals, and especially within new electronic journals, permit inclusion of interactive content as an analogue to the dynamic nature of geological processes. We present a collection of dynamic animations based on previous data. These animations are used to deliver ideas about the kinematic and mechanical development of the Ibero-Armorican orocline and to illustrate the complex evolution and timing of orocline formation, its tectonic setting on a regional and global-scale, and its implications for the modification of the lithosphere during orogeny., Ministerio de Ciencia e Innovación (MICINN), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

This paper reviews multi-proxy paleoclimatic reconstructions with robust age-control derived from lacustrine, dendrochronological and geomorphological records and characterizes the main environmental changes that occurred in the Southern Pyrenees during the last millennium. Warmer and relatively arid conditions prevailed during the Medieval Climate Anomaly (MCA, ca. 900–1300 AD), with a significant development of xerophytes and Mediterranean vegetation and limited deciduous tree formations (mesophytes). The Little Ice Age (LIA, 1300–1800 AD) was generally colder and moister, with an expansion of deciduous taxa and cold-adapted montane conifers. Two major phases occurred within this period: (i) a transition MCA–LIA, characterized by fluctuating, moist conditions and relatively cold temperatures (ca. 1300 and 1600 AD); and (ii) a second period, characterized by the coldest and most humid conditions, coinciding with maximum (recent) glacier advances (ca. 1600–1800 AD). Glaciers retreated after the LIA when warmer and more arid conditions dominated, interrupted by a short-living cooling episode during the late 19th to early 20th centuries. Some records suggest a response to solar activity with colder and slightly moister conditions during solar minima. Centennial-scale hydrological fluctuations are in phase with reconstructions of NAO variability, which appears to be one of the main climate mechanisms influencing rainfall variations in the region during the last millennium, Ministerio de Ciencia e Innovación (MICINN), Organismo Autónomo Parques Naturales, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

We present a palaeoclimatic reconstruction of the last glacial cycle in Iberia (ca. 120,000–11,600 cal yrs BP) based on multi-proxy reconstructions from lake sediments with robust chronologies, and with a particular focus on abrupt climate changes. The selected lake sequences provide an integrated approach from northern Iberia exploring temperature conditions, humidity variations and land-sea comparisons during the most relevant climate transitions of the last glacial period. Thus, we present evidence that demonstrates: (i) cold but relatively humid conditions during the transition from MIS 5 to MIS 4, which prevailed until ca. 60,000 cal yrs BP in northern Iberia; (ii) a general tendency towards greater aridity during MIS 4 and MIS 3 (ca 60,000 to 23,500 cal yrs BP) punctuated by abrupt climate changes related to Heinrich Events (HE), (iii) a complex, highly variable climate during MIS 2 (23,500 to 14,600 cal yrs BP) with the “Mystery Interval” (MI: 18,500 to 14,600 cal yrs BP) and not the global Last Glacial Maximum (LGM: 23,000 to 19,000 cal yrs BP) as the coldest and most arid period. The last glacial transition starts in synchrony with Greenland ice records at 14,600 cal yrs BP but the temperature increase was not so abrupt in the Iberian records and the highest humidity was attained during the Allerød (GI-1a to GI-1c) and not during the Bølling (GI-1e) period. The Younger Dryas event (GS-1) is discernible in northern Iberian lake records as a cold and dry interval, although Iberian vegetation records present a geographically variable signal for this interval, perhaps related to vegetation resilience., CICYT, Gobierno de Aragón, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Selected multi-proxy and accurately dated marine and terrestrial records covering the past 2000 years in the Iberian Peninsula (IP) facilitated a comprehensive regional paleoclimate reconstruction for the Medieval Climate Anomaly (MCA: 900–1300 AD). The sequences enabled an integrated approach to land–sea comparisons and, despite local differences and some minor chronological inconsistencies, presented clear evidence that the MCA was a dry period in the Mediterranean IP. It was a period characterized by decreased lake levels, more xerophytic and heliophytic vegetation, a low frequency of floods, major Saharan eolian fluxes, and less fluvial input to marine basins. In contrast, reconstruction based on sequences from the Atlantic Ocean side of the peninsula indicated increased humidity. The data highlight the unique characteristics of the MCA relative to earlier (the Dark Ages, DA: ca 500–900 years AD) and subsequent (the Little Ice Age, LIA: 1300–1850 years AD) colder periods. The reconstruction supports the hypothesis of Trouet et al. (2009), that a persistent positive mode of the North Atlantic Oscillation (NAO) dominated the MCA., CICYT, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

El agua es un recurso tan escaso como necesario. En regiones donde imperan los climas semiáridos, como es el caso de la mayor parte de la Península Ibérica, la disponibilidad de agua puede estar condicionada por la sequía. El estudio de este riesgo natural está íntimamente relacionado con diversas disciplinas de las Ciencias de la Tierra, como la meteorología o la hidrología. Este artículo describe paso a paso la aplicación de una de las muchas técnicas existentes para el estudio de la sequía: la curva de desviaciones acumuladas. El alumno descarga de internet los datos de precipitación de la ciudad donde reside y los analiza con ayuda de una hoja de cálculo, caracterizando las principales sequías con perspectiva histórica. Por último se proponen diversos ejercicios de interpretación. Con las oportunas modificaciones, este ejercicio es adecuado para un amplio rango de titulaciones., Water is as scarce as it is necessary. Water availability in semiarid regions is often constrained by droughts. The study of droughts pertains to several scientific disciplines, including meteorology and hydrology. This paper presents a step-by-step description of the cumulative rainfall curve, a common technique for drought analysis. Students download historical rainfall data for the town where they live. Thereafter, they carry out a spreadsheet-based analysis to characterize drought from a historical perspective. Finally, a series of additional interpretation exercises are proposed. This exercise is appropriate for a wide range of age groups and courses., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Soil and vegetation are interacting factors controlling erosion. Soil degradation processes may affect the normal tree and shrub development and inversely, vegetation can modulate the velocity and intensity of soil development or denudation. A dendrogeomorphological approach can be used to study these interactions, allowing to obtain a date and estimate mean or specific erosion rates. This is especially useful in an unrecorded badlands and gullied environments,where the scarce vegetationmay be the only proxy available to quantify the different geomorphic processes which have occurred. This paper provides a fundamental review of the dendrogeomorphological methodology applied to erosion measurement in badlands. Focusing on the response of the vegetation to the geomorphic processes, this paper: (a) describes themethodology developed to estimate erosion rates with exposed roots; (b) shows newadvances through case studies; and finally, (c) discusses future lines of research to reduce methodological uncertainties and for making dendrogeomorphology more widely applicable., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, inpress

The Malaga Basin is located in the westernmost part of the Betic Cordillera. This alpine cordillera in the south of Spain is the most active region of the Iberian Peninsula. Some of the most destructive earthquakes occurred historically in Spain took place within the Malaga Basin. In this work we focus on geomorphic and morphotectonic observations in the aim of finding active tectonic structures that could be seismogenic sources. First, we study the spatial arrangement and age of the Quaternary alluvial fan system as well as the drainage pattern of the basin, followed by the analysis of the distribution of regional markers like marine erosive surfaces and the extend of Pliocene marine deposits in the Malaga Basin. The tectonic structures inferred as active by the morphotectonic analysis are grouped into four main families: N60º-85ºE folds associated with blind thrust faults, N20º-30ºE and N40º-50ºE high angle dip-slip faults, and N165º-170ºE tear faults. Finally, their seismic potential in terms of maximum moment magnitude (Mw) is assessed by means of empirical relationships, varying between 6.0 and 7.0 depending on the hypothesis considered., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub