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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 micro-deformations 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., Leica Geosystems, S.L., Forward Modelling Network Deformation Analysis Software, Direccion General de Enseñanza Superior e Investigacion Cientıfica, Unidad Deptal. de Astronomía y Geodesia, Fac. de Ciencias Matemáticas, Instituto de Matemática Interdisciplinar (IMI), TRUE, pub

Las Tablas de Daimiel National Park is a series of wetlands which naturally originated from groundwater discharges from the Mancha Occidental aquifer, Spain. Despite the relatively large size of this aquifer, 30 years of intensive groundwater pumping have significantly depleted the water table. As a result, wetlands only remain functional due to artificial inflows. Infiltration loss is therefore a key parameter to evaluate how much water is needed to maintain ecosystem functionality. Although yearly infiltration estimates existed prior to this work, these did not take into account key parameters such as the temporal evolution of the flooded area. This paper presents a more concrete estimate of the average infiltration losses. Infiltration is calculated as the closure term of daily water balances during a period of time where all other elements were known to an acceptable accuracy. A validation mechanism is provided to check the potential utility of the calculated infiltration in wetland management practices., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

The Granada Basin (Central Betic Cordillera), one of the most seismically active areas of the Iberian Peninsula, is currently subjected to NW-SE compression and NE-SW extension. The present day extension is accommodated by normal faults with various orientations but particularly with a NW-SE strike. At the surface, these active NW-SE normal faults are mainly concentrated on the NE part of the Basin. In this part we have selected a 15-km long segment where several active normal faults crop out. Using the marine Tortonian rocks as a reference, we have calculated a minimum extensional rate of 0.15-0.30 mm/year. The observed block rotation, the listric geometry of faults at depth and the distribution of seismicity over the whole Basin, indicate that this rate is a minimum value. In the framework of an interdisciplinary research project a non-permanent GPS-network has been established in the central sector of Betic Cordillera to monitor the crustal deformations. The first two observation campaigns were done in 1999 and 2000., Dirección General de Enseñanza Superior e Investigación Científica, Unidad Deptal. de Astronomía y Geodesia, Fac. de Ciencias Matemáticas, Instituto de Matemática Interdisciplinar (IMI), TRUE, pub

The Campo de Dalias is an area with relevant seismicity associated to the active tectonic deformations of the southern boundary of the Betic Cordillera. A non-permanent GPS network was installed to monitor, for the first time, the fault- and fold-related activity. In addition, two high precision levelling profiles were measured twice over a one-year period across the Balanegra Fault, one of the most active faults recognized in the area. The absence of significant movement of the main fault surface suggests seismogenic behaviour. The possible recurrence interval may be between 100 and 300 y. The repetitive GPS and high precision levelling monitoring of the fault surface during a long time period may help us to determine future fault behaviour with regard to the existence (or not) of a creep component, the accumulation of elastic deformation before faulting, and implications of the fold-fault relationship, Topo-Iberia, Ministry of Science and Innovation, Unidad Deptal. de Astronomía y Geodesia, Fac. de Ciencias Matemáticas, Instituto de Matemática Interdisciplinar (IMI), TRUE, pub

The coexistence of shortening and extensional tectonic regimes is a common feature in orogenic belts. The westernmost end of the Western Mediterranean is an area undergoing shortening related to the 5 mm/yr NNW‒SSE convergence of the Nubia and Eurasia Plates. In this region, the Central Betic Cordillera shows a regional ENE‒WSW extension. Here, we present GNSS-derived geodetic data along a 170 km-long transect orthogonal to the main active normal faults of the Central Betic Cordillera. Our data indicate that the total extension rate along the Central Betic Cordillera is 2.0 ± 0.3 mm/yr. Extension is accommodated in the eastern (0.8 ± 0.3 mm/yr in the Guadix-Baza Basin) and western (1.3 ± 0.3 mm/yr in the Granada Basin) parts of the Central Betic Cordillera, while no extension is recorded in the central part of the study area. Moreover, our data permit us to quantify, for the first time, short-term fault slip rates of the Granada Fault System, which is one of the main seismogenic sources of the Iberian Peninsula. We deduce a fault slip rate of ∼1.3 ± 0.3 mm/yr for the whole Granada Basin, with 0.9 ± 0.3 mm/yr being accommodated in the Granada Fault System and 0.4 ± 0.3 mm/yr being accommodated in the southwestern sector of the Granada Basin, where no active faults have been previously described at the surface. The heterogeneous extension in the Central Betic Cordillera could be accommodated by shallow high-angle normal faults that merge with a detachment at depth. Part of the active extension could be derived from gravitational instability because of underlying over-thickened crust.

[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