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We present GNSS data from a survey-mode network located in the Central Betic Cordillera. The Betic Cordillera is a collisional orogen, presently undergoing NNW-SSE shortening, as it is located in the convergence limit between Nubia and Eurasia Plates. Our GNSS network includes seven stations along a ca. 170 km long NE-SW striking profile. For these stations we calculated GNSS velocities from position time series. Then we calculated residual velocities with respect to a fixed Eurasia (ITRF2014 plate motion model(Altamimi et al., 2017)'}" id="614029728">).To discuss our data in terms of regional geodynamic implications we projected the velocity vectors along the N060E direction.The absolute value of theN060E component of theobtained vectors shows a general increase of velocity from NE to SW, pointing to a regional NE-SW extension. This is in good agreement with previously reported data. Our data permit us to quantify an extension rate of 2.0±0.3 mm/yr. Furthermore, we also quantify the strain partitioning within the Central Betic Cordillera, including the Guadix-Baza and the Granada basins areas of high extensional rates, separated by a low-deformed crustal horst.Therefore, the Central Betic Cordillera is an area undergoing 2.0±0.3 mm/yr of NE-SW extension within a collisional orogen. Furthermore, this area presents the highest topographic relive of the entire cordillera and anoverthickenedcrust. We thus postulate that the extension quantified by our GNSS data could partially be the consequence of upper crustal extension related to gravitational instability. This instability would be produced by the overthickened crust.&nbsp, The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Reunión Ibérica sobre Fallas Activas y Paleosismología (3ª. 2018. Alicante). - Texto en español con resumen y palabras claves en inglés y español El Mar de Alborán está afectado en su transversal central por una zona de deformación y actividad sísmica NNE-SSO. Tras las series sísmicas de 1993-94 y 2004, ha ocurrido una nueva serie en su sector meridional durante 2016-17 (evento principal Mw = 6.3, 25/01/2016), con epicentros agrupados en dos alineaciones. La septentrional, OSO-ENE, está asociada a mecanismos focales de falla inversa y caracterizada por una zona con depósitos recientes de transporte en masa. La meridional, NNE-SSO, se inicia con eventos localizados de 5 a 10 km al oeste de la falla de Al Idrisi, y posteriormente la zona de deformación se extiende hasta dicha falla. La deformación cercana a la superficie incluye fallas activas verticales y normales NO-SE, identificadas por primera vez, asociadas en profundidad a un segmento mayor de falla sinistra. El desarrollo de nuevas fallas puede generar sismos de mayor magnitud que en fallas preexistentes = The central transect of the Alboran Sea is affected by an NNE-SSW seismic activity band and deformation zone. After the seismic series of 1993-94 and 2004, a new series has occurred in its southern sector during 2016-17 (main event Mw = 6.3, 01/25/2016), with epicenters grouped in two alignments. The northern one, WSW-ENE, is associated with focal mechanisms of reverse faults and characterized by an area with recent mass transport deposits. The southern one, NNE-SSW, starts with localized events from 5 to 10 km west of the Al Idrisi fault, and then the seismicity zone extends towards this fault. The deformation near the surface includes active vertical and normal NW-SE faults, identified for the first time, associated in depth to a larger segment of sinistral fault. The development of new faults can generate earthquakes of greater magnitude than in preexisting faults. Instituto Andaluz de Ciencias de la Tierra, España Departamento de Geodinámica, Universidad de Granada, España Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas, España Real Instituto y Observatorio de la Armada, España Université Pierre et Marie Curie, Francia Université Mohammed Premier, Marruecos Instituto Geológico y Minero de España, España Centro Oceanográfico de Málaga, Instituto Español de Oceanografía, España Facultés de Sciences, Université Mohammed V, Marruecos Faculté des Sciences, Université Abdelmalek Essaadi, Marruecos Instituto Hidrográfico de la Marina, España Departamento de Ingeniería Cartográfica, Geodesia y Fotogrametría, Universidad de Jaén, España Centro de Estudios Avanzados en Ciencias de la Tierra, Universidad de Jaén, España

This study uses the InSAR technique to analyse ground subsidence due to intensive exploitation of an aquifer for agricultural and urban purposes in the Montellano town (SW Spain). The detailed deformation maps clearly show that the spatial and temporal extent of subsidence is controlled by piezometric level fluctuations and the thickness of compressible sediments. The total vertical displacement measured with multi-temporal InSAR, between 1992 and 2010, is 33 mm that corresponds with a decrease of 43 m in the groundwater level. This technique allows monitoring the evolution of settlement related to water level fall in an area where subsidence has not yet been reported by population or authorities through infrastructure damages and to discuss the effect of the aquifer recovery. This information is, therefore, valuable for implementing effective groundwater management schemes and land-use planning and to propose new building regulations in the most affected areas. © 2015, Springer-Verlag Berlin Heidelberg.

Central Alboran Sea constitutes a key area to analyze the relationships between active tectonic structures and moderate seismicity. The heterogeneous crustal layered structure and the propagation of the deformation along the fault zones are key features to relate active faults and seismic hazard. The NW-SE oblique convergence between Eurasian and African plates determines the broad band of tectonic deformation and seismicity along the Alboran Sea basin (westernmost Mediterranean). The Betic-Rif Cordilleras are connected through the Gibraltar Arc and surround the Alboran Sea formed by thinned continental crust. This basin is filled since the Neogene by sedimentary and volcanic rocks. Central Alboran Sea is now undergoing shortening and is mainly deformed by a system of conjugated WNW-ESE dextral and NE-SW sinistral faults with recent activity formed by indenter tectonics related to a heterogeneous crustal behavior. In addition a NNW-SSE normal fault set and large ENE-WSW folds deform the central and northern Alboran Sea. These structures support a present-day N160 E maximum compression and orthogonal extension. In this setting, most of the recent seismicity is concentrated along a NNE-SSW zone that extends landward from Campo de Dalias (SE Spain) to Al Hoceima (Morocco). The Campo de Dalias 1993-1994 seismic crisis reached up to magnitudes Mw= 5.3, while the Al Hoceima area was affected by seismic crisis of 1994 (May 26, Mw=5.6) and 2004 (Feb 24, Mw= 6.4). The main active fault related to the 2004 earthquakes, even that it was a vertical NNE-SSW oriented fault and focal depth was 6 km, did not reach the surface probably due to the presence of a mechanically layered crust. The main active surface faults located in Al Hoceima area (the NNE-SSW transtensional sinistral Trougout fault zone) extended northwards towards the NE-SW sinistral Al Idrissi Fault that intersects the Alboran Sea and are connected with the normal NNW-SSE Balanegra Fault zone. Although these active faults determine most of the seismicity of the central Alboran Sea, the seismic crisis that occurred since January 2016, reaching Mw= 6.3 is located in a region westward of Al Idrissi Fault, underlining the relevance of growth of new faults to determine the seismic hazard of the region. Earthquake focal mechanisms support that the main active fault has a NNE-SSW orientation, similar to Al Idrissi Fault zone. Maximum magnitude suggests a surface rupture length of at least 12 km and a subsurface rupture of 20 km. Propagation of a new fault is more efficient to accumulate elastic deformation, and to produce highest magnitude earthquakes than already formed faults. This new fault is connected probably in deep crustal levels with the blind sinistral fault responsible of the 2004 Al Hoceima earthquake. The tsunami hazard of the region should be consequence of both seabottom displacement due to fault activity and co-seismic submarine landslides. The INCRISIS cruise, scheduled by May 2016, will provide evidences of seabottom effects of this seismic crisis.

There are five tectonic units in the south part of Sierra Espuña; the upper one belongs to the Malaguide Complex, below there are three units of an intermediate character between the Malaguide and Alpujarride complexes, and in the lowest position exists one Alpujarride unit. Several thrust sheets, formely distinguished in previous papers, affecting the Malaguide unit do not exist, merely corresponding to stratigraphic features. The tectonic transport of the units, as indicate the minor structures, show two directions, towards the SSE and the E, according the present coordinates. These units has been affected by reverse faults and folds facing to the S, SE and E, forming an arc convex to the S, feature than can be formed later, caused for the movement of a left strike-slip and normal fault, affecting the SE border of Sierra Espuña. This sierra has undergo an important uplift, at least of 825 m in sorne points, from the Late Miocene to the presento The existence of intermediate units between the Malaguide and Alpujarride complexes, show that the paleogeographic passage between both complexes was not sharp, but gradual.En la parte sur de Sierra Espuña existen cinco unidades tectónicas, la superior del complejo Maláguide, debajo tres de carácter intermedio y en posición inferior una unidad alpujárride. Varias escamas tectónicas descritas en anteriores trabajos dentro de la unidad maláguide no existen sino que corresponden alternancias puramente estratigráficas. El desplazamiento tectónico de las unidades, de acuerdo con las vergencias de las estructuras menores se produjo hacia el SSE y hacia el E, según las coordenadas actuales. Los grandes pliegues y las fallas presentan vergencias hacia el S, SE y E, formando un arco convexo hacia el S, debido al arrastre producido por la falla de desgarre sinistrorsa y normal del borde SE de Sierra Espuña. Esta sierra ha sufrido un notable levantamiento, de 825 m al menos en algunos puntos, desde el Mioceno superior a la actualidad. La existencia de las unidades intermedias entre el complejo Maláguide y el Alpujárride, indica que el tránsito paleogeográfico entre ambos complejos no fue brusco sino progresivo.

Two Alpujarride units and, in a lower tectonic position, one unit of the Ballabona-Cucharón Complex have been differentiated in the Mazarrón-Cartagena sector. According to the new mapping carried out in the region, the first two units are considered as forming a single unit and, at the same time, the third unit is included in the Alpujarride Complex. During the Triassic, the sedimentation of these units occurred in a less subsident paleogeographic domain if compared with other westernly Alpujarride domains. During the Early Triassic, metapelitic formations were deposited, whereas the age of the carbonatic formations comprises the Ladinian and Camian. In the Carnian, terrigenous sediments showing similar features to those of the Malaguide Complex were deposited. Norian deposits have not been identified so that we postulate that they did not form or are very scarcely represented.En el sector comprendido entre Mazarrón y Cartagena, se habían descrito dos unidades alpujárrides, más una tercera de tipo Ballabona-Cucharón debajo de las anteriores. En este trabajo, tras realizar una nueva cartografía, se engloban las dos primeras unidades en una sola y la tercera unidad se incluye en el Alpujárride. La sedimentación en estas unidades alpujárrides, durante el Triásico, tuvo lugar en un dominio paleogeográfico menos subsidente que en otros más occidentales del Alpujárride. Durante el Triásico Inferior se depositaron las formaciones metapelíticas, mientras que las formaciones carbonatadas abarcan edades comprendidas entre el Ladiniense y el Camiense. En el Carniense se depositaron sedimentos terrígenos de aspecto muy similar a los del Complejo Maláguide para esta edad. Los materiales más altos de la serie estudiada pueden ser ya de edad Noriense, por su similitud en cuanto a litofacies a los materiales de esta edad en otras unidades alpujárrides, pero en todo caso su representación sería muy escasa.

The Romero and Carrascoy units defined by Kampschuur (1972) have common stratigraphic series, with several changes in its facies and thickness, although these changes are not situated in the hypothetic contact between both units. Similarly, from a tectonic point of view it is not possible to maintain the differentiation between these units, because usually they pass each other stratigraphically with no faults involved. For this reason we discard, at least in this area the differentiation between the Almagride Complex (Romero D.) and the Alpujarride (Carrascoy D.) and we thus suggest that they all belong to the Alpujarride Complex. The structure of this area is complex, not only by the thrustings, but specially by the opposed vergences observed in the E-W folds, southwards in the northern area and progressively northwards in the southern area of the Sierra. Moreover, N-S folds verging to the W, are also observed.Las unidades de Romero y de Carrascoy definidas por Kampschuur (1972) tienen una serie estratigráfica común, con algunos cambios de facies y potencias, aunque éstos no se localizan en el hipotético contacto entre ambas. Igualmente, desde el punto de vista tectónico no se puede mantener su diferenciación, pues generalmente el paso de los afloramientos atribuidos a una de estas unidades a los de la otra es estratigráfico. Por ello, descartamos la diferenciación previamente existente en este sector entre complejo Almágride (D. de Romero) y Alpujárride (D. de Carrascoy), siendo el conjunto de los materiales atribuible al Alpujárride. La estructura del sector estudiado es bastante compleja, no sólo por los cabalgamientos existentes, sino sobre todo por las vergencias opuestas que presentan los pliegues E-O; hacia el sur los situados en la parte N de la Sierra y progresivamente hacia el norte conforme se va al S de la misma. Existen además pliegues de dirección N-S con vergencias al O.

14 pages, 6 figures., [EN] The contact between the Internal Betic-Rif Zone and the corresponding external zones is not regular, sorne sections having a NNE-SSW direction and others approximately EW. These latter coincide with sorne of the corridors of the Internal Zone, and have continuity with those within this zone. A model which relates the two features is proposed, in which the corridors originally corresponds to faults or fault zones which are the eastern continuation of the transcurrent contacts, by means of which the Internal Zone advanced westwardly more easily on its collision with the External Betic Zone. This means that the Internal Zone is divided into various cortical segments and advanced towards the west. The proposal of the model ineludes a discussion of the Alpujarras and Colmenar corridors, which continue each other, and provides values for the displacement of the zone of faults. With this model, both the transcurrent E-W fauits of the Internal Zone, as well as at least part of the extensional movements affecting this zone, remain subordinate to the shifting of the Internal Zone towards the west., [ES] El contacto entre la Zona Interna Bético-Rifeña y las correspondientes zonas externas no es regular. Muestra unos sectores de dirección NNE-SSW y otros que son aproximadamente E-W; estos últimos coinciden con algunos de los corredores de la Zona Interna y están en continuidad con los que existen dentro de la misma. Se propone un modelo en el que se relacionan genéticamente ambos rasgos, de manera que los corredores corresponden originalmente a fallas o zonas de fallas que son la continuación de los contactos transcurrentes más occidentales, por medio de los cuales la Zona Interna ha logrado avanzar con más facilidad hacia el W en su choque con la Zona Externa Bética. Esto significa que la Zona Interna está dividida en varios segmentos corticales y que el avance de la misma se hizo fundamentalmente hacia el W. En la propuesta del modelo se discuten los corredores de las Alpujarras y de Colmenar, situados en continuidad mutua, y se dan los valores de desplazamiento del conjunto de las fallas. Con este modelo, tanto las fallas transcurrentes E-W de la Zona Interna, como al menos parte de los movimientos extensionales ocurridos en la misma, quedan subordinados a la traslación de la Zona Interna Bético-Rifeña hacia el W., This work belongs to the project PB94-00S0 (CICYT) and PB92-0l84-C02-01 (DGICYT).

The Sierra de Abdalajís-Huma sector is part of the Penibetic and its structure mainly corresponds to dextral strike-slip faults of approximate N70ºE direction. These faults are vertical or strongly dipping, with predominantly northward reverse component. There are also large anticlinal and synclinal folds. From the study of minor structures, a main compression of WNW-ESE direction that was progressively rotated to a NNW-SSE direction can be deduced. Folds limbs are commonly vertical, especially near the contact with the Internal Zone, which in this sector is a major vertical dextral fault. The structure of the area is related to the lateral oblique collision of the Internal Zone, then moving to the west. The movement between the two domains caused a relative eastward displacement of the Penibetic situated to the north of the Internal Zone. However the absolute displacement of both domains was to the west, although the northern part of the Penibetic did to a lesser degree. El sector de las sierras de Abdalajís y de Huma forma parte del Penibético y su estructura corresponde a fallas dextrorsas de dirección aproximada N70ºE. Son verticales o fuertemente buzantes, con componente inversa y vergencia predominante hacia el norte. Existen también grandes pliegues anticlinales y sinclinales, de varios kilómetros de longitud. Las abundantes estructuras menores permiten deducir una compresión dominante que tuvo dirección ONO-ESE y que fue rotando a la dirección NNO-SSE. Muchos de los flancos de los pliegues son verticales, particularmente en las proximidades del contacto con la Zona Interna, el cual, en este sector, es una gran falla dextrorsa vertical. La estructura del área estudiada está relacionada con la colisión lateral oblicua de la Zona Interna que se desplazaba al O. El movimiento entre ambos dominios provocó un desplazamiento relativo hacia el E del Penibético situado al N de la Zona Interna. No obstante el movimiento absoluto de los dos dominios fue hacia el O, si bien esa parte norte del Penibético lo hizo en menor grado.

The Subbetic sierras of Las Cabras to the Gibalto form an arched structure, giving it a high relief, constituted by many tectonic slices, verging to the South in its southern border and to the North and West in its concave border. Although it could be interpreted as an allochthonous structure, really is rooted in the transitional area between the Median and the Internal Subbetic. Several local factors have influenced this complex structure, but the final cause is the oblique collision (transpression) of the In-ternal Zone against External Zone of the Betic Chain, producing an important strike-slip system. Las sierras subbéticas de las Cabras al Gibalto forman una estructura arqueada, que da un fuerte relieve, constituida por escamas tectónicas, vergentes al sur en su borde convexo, meridional, y al nor-te y oeste en su borde cóncavo. Aunque podría interpretarse como una estructura alóctona, se en-cuentra enraizada en el área de tránsito entre el Subbético Medio y el Interno. En su génesis han in-fluido varios factores locales pero la causa que controla a todos ellos es la colisión oblicua, en trans-presión, de la Zona Interna Bética contra la Externa, que produjo un importante sistema de desgarre.