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[EN] The Campo de Dalias GNSS network monitors since 2006 the active tectonic deformation of the most seismic area on the boundary of the Alboran Sea and the Betic Cordillera. The residual deformation rates determined with respect to Eurasia range from 1.7 to 3.0 mm/yr. The displacements are roughly homogenous towards WSW of the northern sites while the southern sites evidence irregular displacements towards the W and NW. This deformation pattern supports simultaneous NNWSSE shortening that develops ENE-WSW folds and ENE-WSW extension, accommodated by normal and oblique faults. Moreover, the GNSS results point to dextral kinematics of the main NW-SE Balanegra Fault, that was previously considered as a normal fault. These GNSS results thus reveal, for the first time, present-day interaction of the roll-back tectonics of the Rif-Gibraltar-Betics slab in the western part of the Gibraltar Arc with the indentation tectonics affecting the eastern and southern areas, providing new insights for seismic hazard studies in this region, [ES] La red GNSS del Campo de Dalias monitoriza desde 2006 la deformación tectónica activa de la zona con mayor sismicidad del límite entre la Cordillera Bética y el Mar de Alborán. Las velocidades de deformación residuales calculadas con respecto a Eurasia oscilan entre 1,7 y 3,0 mm/año. Los desplazamientos son aproximadamente homogéneos hacia el OSO de las estaciones del norte, mientras que las estaciones del sur evidencian desplazamientos irregulares hacia el O y el NO. Este patrón de deformación indica el acortamiento NNO-SSE que desarrolla pliegues ENE-OSO simultáneo a la extensión ENEOSO, acomodada por fallas normales y oblicuas. Además, los resultados de la red GNSS indican un salto dextro de la falla de Balanegra, con orientación NO-SE, que había sido considerada anteriormente como una falla normal. Las redes GNSS revelan, por primera vez, la interacción actual de la tectónica de roll-back asociada a la subducción Rif-Gibraltar-Bética en la parte occidental del Arco de Gibraltar y la tectónica de indentación que afecta a las zonas oriental y meridional del Mar de Alborán. Además, proporciona nuevos datos para los estudios de peligrosidad sísmica en esta región

The Gibraltar Arc includes the Betic and Rif Cordilleras surrounding the Alboran Sea; it is formed at the northwest–southeast Eurasia–Nubia convergent plate boundary in the westernmost Mediterranean. Since 2006, the Campo de Dalias GNSS network has monitored active tectonic deformation of the most seismically active area on the north coast of the Alboran Sea. Our results show that the residual deformation rates with respect to Eurasia range from 1.7 to 3.0 mm/year; roughly homogenous west-southwestward displacements of the northern sites occur, while the southern sites evidence irregular displacements towards the west and northwest. This deformation pattern supports simultaneous east-northeast–west-southwest extension, accommodated by normal and oblique faults, and north-northwest–south-southeast shortening that develops east-northeast–west-southwest folds. Moreover, the GNSS results point to dextral creep of the main northwest–southeast Balanegra Fault. These GNNS results thus reveal, for the first time, present-day interaction of the roll-back tectonics of the Rif–Gibraltar–Betic slab in the western part of the Gibraltar Arc with the indentation tectonics affecting the eastern and southern areas, providing new insights for improving tectonic models of arcuate orogens

[EN] In this work a regional inventory of landslides is constructed by the observation of the morphology of the continental margin of Palomares (Western Mediterranean), with the aim of studying the role of these processes in the regional geology. The analysis of the bathymetry of the margin has led to the identification of 937 events, mobilizing a total sediment volume of 10.34 km3. For each event, morphometric parameters which are considered relevant for the study of landslides have been measured. [EN] The magnitude-frecuency statistical analysis carried out shows that the data set can be fitted by both an inverse power law (partial fit for the two largest orders of magnitude) and a log-normal function (fit of the whole inventory). The latter allows to define a characteristic event size for each zone which is determined by the geomorphologic conditions and a variance related to the features of the regional triggers (mainly landslides), [ES] En este trabajo se elabora un inventario de inestabilidades sedimentarias a partir del análisis de la morfología del margen continental de Palomares (Mediterráneo Occidental) con el objetivo de estudiar el papel de estos procesos en la geología regional. El análisis de datos batimétricos del margen ha permitido identificar 937 eventos que movilizan un volumen total de sedimento de aproximadamente 10.34 km3. Para cada evento se han medido distintos parámetros morfométricos relevantes para el estudio de inestabilidades. El análisis estadístico de magnitud-frecuencia llevado a cabo indica que el conjunto de datos se puede ajustar tanto a una potencia inversa (ajuste parcial para los dos órdenes de magnitud mayores) como a una función log-normal (ajuste de la totalidad del inventario). Éste último permite definir un tamaño de evento característico para cada zona determinado por las condiciones geomorfológicas y una varianza ligada a las características de los detonantes que afectan la región (terremotos)

One of the most significant parameters for seismic hazard assessment analyses is the fault slip rate. The combination of both geological (long-term) and geodetic (short-term) data offers a more complete characterization of the seismic potential of active faults. Moreover, geodetic data are also a helpful tool for the analysis of geodynamic processes. In this work, we present the results of a local GPS network from the Baza sub-Basin (SE Spain). This network, which includes six sites, was established in 2008 and has been observed for seven years. For the first time, we obtain short-term slip rates for the two active faults in this area. For the normal Baza Fault, we estimate slip rates ranging between 0.3 ± 0.3 mm/yr and 1.3 ± 0.4 mm/yr. For the strike-slip Galera Fault, we quantify the slip rate as 0.5 ± 0.3 mm/yr. Our GPS study shows a discrepancy for the Baza Fault between the short-term slip rates and previously reported long-term rates. This discrepancy indicates that the fault could be presently in a period with a displacement rate higher than the mean of the magnitude 6 seismic cycle. Moreover, the velocity vectors that we obtained also show the regional tectonic significance of the Baza Fault, as this structure accommodates one-third of the regional extension of the Central Betic Cordillera. Our GPS-related slip rates form the basis for future seismic hazard analysis in this area. Our results have further implications, as they indicate that the Baza and Galera Faults are kinematically coherent and they divide the Baza sub-Basin into two tectonic blocks. This points to a likely physical link between the Baza and Galera Faults; hence, a potential complex rupture involving both faults should be considered in future seismic hazard assessment studies.

The NW-SE Eurasian-African plate convergence formed the Rif and Betic Cordilleras around the Alboran Sea in the westernmost Mediterranean. Seismicity in this region is notably concentrated along a NE-SW band crossing from the Campo de Dalías, in Betics (Spain), to the Al Hoceima region in the Rif (Morocco), an area affected by the 1994, 2004 and 2016 onshore and offshore seismic series. This deformation zone has been proposed to be a main segment of the plate boundary and corresponds to the northwestern limit of a rigid basement spur of the African plate in a setting of indentation tectonics. The onshore Al Hoceima region was affected by the catastrophic earthquake of January 24, 2004 (M= 6.4, depth 7 to 10 km) and the related seismic series is characterized by strike-slip focal mechanisms supporting the presence of NNE-SSW sinistral or WNW-ESE dextral faults. However, there is not any evidence of surface strike-slip faults in the epicentral area, which instead was affected by minor NE-SW extensional structures evidenced by fractures in Quaternary pebbles, minor conjugate normal faults, and vertical open joints. Geological researches evidence that main normal and transtensional faults are located eastward of the epicentral area, onshore and offshore of the Nekor bay, and westward in the Bokoya Massif. A non-permanent GPS network consisting of 6 sites has been installed since June 2007, and we have obtained yearly measurements. They provide an accurate result of the present-day deformation field that is helping to solve the apparent disagreement between seismological and geological observations. The three sites located east of the 2004 series epicentral area have motions roughly consistent with the Nubia (African) plate and evidence the very low activity of the prominent Plio-Quaternary Nekor basin faults. Contrasting, the three sites located on the epicentral and western region undergone a very fast motion (between 2 and 3 mm/yr) towards the WSW with respect to stab

A new continuous GPS network was installed under the umbrella of a research project called "Geociencias en Iberia: Estudios integrados de topografía y evolución 4D (Topo-Iberia)", to improve understanding of kinematic behavior of the Iberian Peninsula region. Here we present a velocity field based on the analysis of the 4 years of data from 25 stations constituting the network, which were analyzed by three different analysis groups contributing to the project. Different geodetic software packages (GIPSY–OASIS, Bernese and GAMIT) as well as different approaches were used to estimate rates of present day crustal deformation in the Iberian Peninsula and Morocco. In order to ensure the consistency of the velocity fields determined by the three groups, the velocities obtained by each analysis center were transformed into a common Eurasia Reference Frame. After that, the strain rate field was calculated. The results put in evidence more prominent residual motions in Morocco and southernmost part of the Iberian Peninsula. In particular, the dilatation and shear strain rates reach their maximum values in the Central Betics and northern Alboran Sea. A small region of high shear strain rate is observed in the east-central part of the peninsula and another deformation focus is located around the Strait of Gibraltar and the Gulf of Cadiz

An experiment was conducted to evaluate the growth performance (average daily gain, ADG; average daily feed intake, ADFI; feed:gain ratio, FGR; fat free lean gain, FFLG), the carcass characteristics (Longissimus muscle area, LMA; backfat thickness, BFT; lean meat percentage, LMP), the plasma urea nitrogen concentration, and the fecal microbial population of 36 hybrid (Yorkshire×Duroc×Pietrain) barrows in nursery (11.10 ± 0.51 kg), growing (25.75 ± 1.13 kg), and finishing (51.03 ± 2.20 kg) phases of fattening in response to two levels of crude protein (CP; nursery: 20.5 and 16.0 %; growing: 16.0 and 14.5 %; and finishing: 14.0 and 12.5 %) and two levels of probiotic (PRO) Enterococcus faecium (0.0 and 1.0 kg t -1 of food at each stage) in sorghum- soybean meal diets, in a completely randomized design with 2×2 factorial arrangement, with 9 replicates per treatment. The energy remained constant at 3.265 Mcal kg -1 . In nursery pigs, the addition of PRO reduced (p≤0.05) LMA, but did not affect (p>0.05) other variables. The plasma urea nitrogen decreased (p≤0.05) in pigs fed low- protein diets. In growing and finishing pigs, the reduction of CP decreased (p≤0.01) plasma urea nitrogen concentration, but did not affect (p>0.05) other variables. The addition of PRO increased (p≤0.05) the concentration of Enterococcus and total fecal bacteria at all stages. These results indicate that adding PRO increases the total microbial population and the population of Enterococcus, although it does not affect the growth performan- ce, the carcass characteristics, and the concen- tration of plasma urea nitrogen of pigs fed stan- dard or low-protein diets., Se evaluó el comportamiento productivo (ga- nancia diaria de peso, GDP; consumo de alimento, COA; conversión alimenticia, CA; ganancia de carne magra, GCM), las características de la canal (área del músculo Longissimus, AML; grasa dor- sal, GD; porcentaje de carne magra, CM), la con- centración de urea en plasma, y la población microbiana en heces de 36 cerdos machos cas- trados híbridos (Yorkshire×Duroc×Pietrain) en iniciación (11,10 ± 0,51 kg), crecimiento (25,75 ± 1,13 kg), y finalización (51,03 ± 2,20 kg), en respuesta a dos niveles de proteína bruta (PB; iniciación: 20,5 y 16,0 %; crecimiento: 16,0 y 14,5 %; y finalización: 14,0 y 12,5 %) y dos niveles del probiótico (PRO) Enterococcus faecium (0,0 y 1,0 kg t -1 de alimento en cada etapa) en dietas sorgo- pasta de soya, en un diseño completamente al azar con arreglo factorial 2×2, con 9 repeticiones por tratamiento. La energía se mantuvo constante en 3,265 Mcal kg -1 . En iniciación, la adición del PRO redujo (p≤0,05) el AML, pero no afectó (p>0,05) otras variables en estudio; la urea en plasma disminuyó (p≤0,05) en cerdos alimentados con baja proteína. En crecimiento y finalización, al reducir la PB disminuyó (p≤0,01) la urea en plas- ma, pero no afectó (p>0,05) otras variables. Agre- gar PRO aumentó (p≤0,05) la concentración de Enterococcus y el total de bacterias en heces en todas las etapas. Estos resultados indican que agregar PRO aumenta la población microbiana total y de Enterococcus, pero no afecta la res- puesta productiva, las características de la canal, ni la concentración de urea en plasma de cerdos alimentados con dietas estándar o con baja pro- teína.

The Betic Cordillera, located in the south of the Iberian Peninsula, is currently subjected to NW-SE compression and NE-SW extension. Until a few years ago, there were hardly any geodetic studies to quantify the tectonic deformation taking place in the Betic Cordillera. In 1999, in the framework of an interdisciplinary research project to monitor the deformation, several geodetic studies were initiated by the Universities of Jaén, Granada and Alicante. These studies were centred on the basins of Granada and the Bajo Segura (Alicante), sectors in which the last two destructive earthquakes in the Iberian Peninsula took place. This paper describes the geodynamic context of these study areas and the main features of the geodetic studies, focusing on the deformation analysis of the three observation surveys carried out in 1999, 2000 and 2001 over a non-permanent GPS network established in the Granada Basin. The results agree with the low rates of deformation previously calculated from geological data. To detect such small rates, observation over a longer time span will be needed.

The Granada basin, located in the central sector of the Betic Cordillera, is one of the most seismically active zones of the Iberian Peninsula. For the first time, a geodetic network along the Padul fault and two levelling profiles (Genil and Viznar) crossing the Granada fault were operated to detect crust microdeformations in this area. Three years of terrestrial geodetic measurements are analysed to characterize the behaviour of these faults in a low to moderate strain rate environment. After the comparison of these three campaigns, we can conclude that there is no significant short-term movement of the Padul fault. Granada fault measurements show significant differences between 1999 and 2001 campaigns in Viznar profile. However, more data are needed to correlate this displacement to the tectonic activity.