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Inciativa Ibérica para el Estudio de las Fallas Activas, Tercera Reunión Ibérica sobre Fallas Activas y Paleosismología IBERFAULT 2018 - Third Iberian Meeting on Active Faults and Paleoseismology, 11-13 June 2018, Alicante, Spain.-- 4 pages, 4 figures, The Gulf of Cadiz is located at the SW Iberian Margin and hosts the African-Eurasian plate boundary. This is one of the most seismogenic areas in Western Europe, where historical and instrumental earthquakes occurred, ranging from Mw 6 to 8.5, and some of them triggered destructive tsunamis. The ICM-CSIC team keeps investigating the Gulf of Cadiz area since more than 15 years, carrying out multiscale bathymetric, high-resolution to deep seismic and sampling surveys. The active structures in the Gulf of Cadiz can be classified in two main families: The WNW-ESE dextral strike-slip faults and the NE-SW thrusts faults. The orientation of these faults is compatible with the current plate convergence in the region. The largest active strike-slip faults are: -the Lineament South and the Lineament North that may generate earthquakes up to Mw 8; while the active NE-SW thrust faults, the Marquês de Pombal, the Horseshoe and the Coral Patch Ridge faults can individually generate earthquakes up to Mw7.8

Inciativa Ibérica para el Estudio de las Fallas Activas, Segunda Reunión Ibérica sobre Fallas Activas y PaleosismologíaI IBERFAULT 2014, 22-24 de octubre de 2014, Lorca, España.-- 4 pages, 2 figures, Newly acquired high-resolution multichannel seismic profiles together with bathymetric and subbottom profiler data from the external part of the Gulf of Cadiz (Iberia-Africa plate boundary) reveal active deformation involving old (Mesozoic) oceanic lithosphere. This area is located 180 km offshore the SW Iberian Margin and embraces the prominent NE-SW trending Coral Patch Ridge, and part of the surrounding deep Horseshoe and Seine abyssal plains. E-W trending dextral strike-slip faults showing surface deformation of flower-like structures predominate in the Horseshoe Abyssal Plain, whereas NE-SW trending compressive structures prevail in the Coral Patch Ridge and Seine Hills. Although the Coral Patch Ridge region is characterized by subdued seismic activity, the area is not free from seismic hazard. Most of the newly mapped faults correspond to active blind thrusts and strike-slip faults that are able to generate large magnitude earthquakes (Mw 7.2–8.4). This may represent a significant earthquake and tsunami hazard that has been overlooked so far, The authors acknowledge the support of the Spanish Ministry of Science and Innovation (MICINN) through National Projects EVENT (CGL2006–12861-C02-02) and SHAKE (CGL2011–30005-C02-02); the European Transnational Access SALVADORE program of the EU (RITA-CT-2004-505322), the ESF EuroMargins SWIM project (01- LEG-EMA09F and REN2002-11234E-MAR), the EU program ‘‘Global Change and Ecosystems’’ contract n. 037110 (NEAREST), and the ESF TopoEurope TOPOMED project (CGL2008-03474-E/BTE). We also acknowledge funding from the MICINN through the ‘‘Ramon y Cajal’’ program (R. Bartolome) and from the CSIC through a JAE Pre-Doc fellowship (S. Martínez-Loriente). This work was carried out within the Grups de Recerca de la Generalitat de Catalunya B-CSI (2009 SGR 146)

Inciativa Ibérica para el Estudio de las Fallas Activas, Segunda Reunión Ibérica sobre Fallas Activas y PaleosismologíaI IBERFAULT 2014, 22-24 de octubre de 2014, Lorca, España.-- 4 pages, 2 figures, [EN] A small amount of the total strain produced by the convergence between the Nubian and Eurasian plates is accommodated in the Alboran Sea basin by different fault systems. High resolution bathymetric maps show several NE-SW lineaments across the Djibouti High, among them the Djibouti fault, that have lengths up to 30 km and are apparently offsetting the Adra Ridge in a right-lateral movement. High-resolution multichannel seismic profiles acquired in the area show that these lineaments correspond to faults that are displacing the reflectors corresponding to the Plio-Quaternary units and some of the faults affect the seafloor. Therefore, these lineaments are associated to Quaternary active faults and their location and characterization improves our knowledge about earthquake and tsunami hazard around the Alboran Sea, [ES] Una fracción de la deformación producida por la convergencia entre las placas de Nubia y Eurasia es acomodada en la cuenca del Mar de Alborán por diferentes sistemas de fallas. En los mapas batimétricos de alta resolución hemos identificado varios lineamientos con dirección NE-SW a través del Alto de Djibouti. Estos lineamientos, destacando entre ellos el correspondiente a la falla de Djibouti, tienen longitudes de hasta 30 km y aparentemente desplazan la Cresta de Adra en sentido lateral derecho. Los perfiles de sísmica multicanal de alta resolución adquiridos en la zona muestran que estos lineamientos corresponden a fallas que están rompiendo los reflectores correspondientes a las unidades Plio-Cuaternarias y en algunos casos incluso la superficie del fondo marino. Por lo tanto, estos lineamientos estás asociados a fallas activas Cuaternarias y su localización y caracterización ayuda a mejorar nuestro conocimiento sobre la peligrosidad sísmica y de tsunamis alrededor del Mar de Alborán, The authors acknowledge the support of the Spanish Ministry of Science and Innovation through National Projects IMPULS (REN2003-05996MAR), EVENT (CGL 2006-12861 C02-02) and SHAKE (CGL 2011-30005-C02-02); Acciones Complementarias EVENT-SHELF (CTM 2008-03346-E/MAR) and SPARKER (CTM 2008-03208-E/MAR); and ESF TopoEurope TOPOMED project (CGL 2008-03474-E/BTE). Hector Perea is fellow researcher at ICM-CSIC under the Juan de la Cierva contract nº JCI-2010-07502 funded by the Spanish Ministry of Science and Innovation

Inciativa Ibérica para el Estudio de las Fallas Activas, Segunda Reunión Ibérica sobre Fallas Activas y PaleosismologíaI IBERFAULT 2014, 22-24 de octubre de 2014, Lorca, España.-- 4 pages, 2 figures Newly acquired high-resolution multichannel seismic profiles together with bathymetric and subbottom profiler data from the external part of the Gulf of Cadiz (Iberia-Africa plate boundary) reveal active deformation involving old (Mesozoic) oceanic lithosphere. This area is located 180 km offshore the SW Iberian Margin and embraces the prominent NE-SW trending Coral Patch Ridge, and part of the surrounding deep Horseshoe and Seine abyssal plains. E-W trending dextral strike-slip faults showing surface deformation of flower-like structures predominate in the Horseshoe Abyssal Plain, whereas NE-SW trending compressive structures prevail in the Coral Patch Ridge and Seine Hills. Although the Coral Patch Ridge region is characterized by subdued seismic activity, the area is not free from seismic hazard. Most of the newly mapped faults correspond to active blind thrusts and strike-slip faults that are able to generate large magnitude earthquakes (Mw 7.2–8.4). This may represent a significant earthquake and tsunami hazard that has been overlooked so far The authors acknowledge the support of the Spanish Ministry of Science and Innovation (MICINN) through National Projects EVENT (CGL2006–12861-C02-02) and SHAKE (CGL2011–30005-C02-02); the European Transnational Access SALVADORE program of the EU (RITA-CT-2004-505322), the ESF EuroMargins SWIM project (01- LEG-EMA09F and REN2002-11234E-MAR), the EU program ‘‘Global Change and Ecosystems’’ contract n. 037110 (NEAREST), and the ESF TopoEurope TOPOMED project (CGL2008-03474-E/BTE). We also acknowledge funding from the MICINN through the ‘‘Ramon y Cajal’’ program (R. Bartolome) and from the CSIC through a JAE Pre-Doc fellowship (S. Martínez-Loriente). This work was carried out within the Grups de Recerca de la Generalitat de Catalunya B-CSI (2009 SGR 146)

Masana, E. ... et al.-- Inciativa Ibérica para el Estudio de las Fallas Activas (IBERFAULT), Primera Reunión Ibérica sobre Fallas Activas y Paleosismología - Primeira Reunião Ibérica sobre Falhas Activas e Paleossismologia - First Iberian Meeting on Active Faults and Paleoseismology, 27-29 de Octubre de 2010, Sigüenza, Guadalajara, España.-- 4 pages, 1 figure, [EN] The southeastern Iberian Peninsula shows a wide distribution of seismicity, which together with the very slow plate convergence rate (4-5,6mm/yr) suggests, the presence of a number of hidden seismogenic faults widespread and slow-moving. Few of these faults have produced catastrophic historical earthquakes and the rest have remained silent historically owing to their very long recurrence periods. In this study we present a synthesis of the paleoseismic studies performed along different faults of the Eastern Betic Shear Zone that allowed us to detect seismogenic faults (Carboneras, Alhama de Murcia and Bajo Segura faults) and characterize their seismic potential (recurrence periods between 10 and 20 ka and likely maximum magnitudes of Mw7). We used a paleoseismic approach, but given the slow moving nature of these faults and the onshore-offshore trace of some faults we had to add other techniques such as high-resolution geophysics or alternative dating techniques (10Be or OSL in Kfelspars). GPS values are also integrated in the study, [ES] La sismicidad en el sureste de la Península Ibérica se encuentra repartida en una amplia franja. Esto, junto con la baja velocidad de convergencia tectónica (4-5,6 mm/a) sugiere la existencia de fallas sismogenéticas no detectadas, con baja velocidad de deformación y distribuidas ampliamente. Algunas de ellas han producido terremotos históricos catastróficos pero posiblemente gran parte está por detectar ya que su periodo de recurrencia puede ser muy largo. En esta comunicación presentamos una síntesis de los resultados de los estudios paleosísmicos realizados en diferentes fallas de la Zona de Cizalla de las Béticas Orientales (ZCBO). Con ellos se han detectado fallas sismogenéticas (fallas de Carboneras, Alhama de Murcia y Bajo Segura) y se ha caracterizado su potencial sísmico (valor máximo de recurrencia entre 10 y 20 ka y Magnitud máxima Mw 7). Para ello se usaron técnicas paleosismologicas aunque, dada la baja velocidad de las fallas y la penetración de algunas fallas en mar, se realizó un esfuerzo para incorporar otras técnicas como geofísica de alta resolución o métodos de datación como 10Be y OSL en feldespatos potásicos. Los primeros resultados GPS de la zona se integraron también en el estudio, This work was founded by the Spanish Ministerio de Educación y Ciencia through the EVENT project (CGL2006-12861-C02-01/BTE) and was also supported by the Consolider-Ingenio 2010 programme, under CSD2006-0004 "Topo-Iberia"