La interpretacion de una malla de perfiles sismicos de reflexion, monocanal y multicanal, ha perm... more La interpretacion de una malla de perfiles sismicos de reflexion, monocanal y multicanal, ha permitido analizar las estructuras neotectonicas en el sector central del margen septentrional del mar de Alboran. La plataforma marginal de Djibouti es un area elevada, caracterizada por la presencia de un conjunto de montes submarinos de origen tanto estructural como volcanico. Bajo esta plataforma se encuentra la Cuenca de Motril que tiene un origen extensional, si bien su geometria ha sido modificada desde el Mioceno superior. Sus bordes y su interior estan deformados mediante estructuras compresivas con el desarrollo de pliegues y estructuras de inversion de antiguas fallas normales. Ademas, se ha reconocido la presencia de fallas en direccion sinestrales de orientacion NE-SO a NNE-SSO, y destrales de tendencia NO-SE que controlan tanto la geometria actual de esta cuenca como la propia fisiografia.
Between Africa and the Iberian Peninsula the oblique convergence is assumed in an ill-defined pla... more Between Africa and the Iberian Peninsula the oblique convergence is assumed in an ill-defined plate boundary. This boundary contains four different zones corresponding to the here named as Oceanic Area, Gulf of Cadiz, Alboran Sea and Algerian Margin. West of Gibraltar, a simple-shear tectonic regime together with a strong mechanical coupling can be considered, being the deformation concentrated in several main faults. An effective transmission of the deformation occurs along the Portuguese Margin. In the Alboran Sea, the convergence is assumed by means of a pure-shear tectonic regime and the deformation is highly distributed. This central sector is characterized by a weak mechanical coupling with no effective transmission of the deformation towards the interior of the Iberian Peninsula. In the Algerian Margin, the deformation is more concentrated and a strong coupling can be considered.
Comision Interministerial de Ciencia y Tecnologia - CICYT.-- Direccion General de Investigacion C... more Comision Interministerial de Ciencia y Tecnologia - CICYT.-- Direccion General de Investigacion Cientifica y Tecnica - DGICYT.--
The spatial distribution of the drainage pattern, the subsurface flow and the maximum values of t... more The spatial distribution of the drainage pattern, the subsurface flow and the maximum values of transmisivity in the aquifer of El Campo de Montiel, as well as the localisation of the springs of the Lagunas de Ruidera, can be explained as a result of the activity of a weak intraplate compressive stress field transmitted from the Betic border
Central Iberia constitutes one of the best natural laboratories to study Alpine intraplate deform... more Central Iberia constitutes one of the best natural laboratories to study Alpine intraplate deformation of the older Variscan basement because of far field effects of plate bound-aries. During the last decade, a great effort has been made to explain the tectonic evolution of the area by different approaches such as, geological mapping and sec-tion balancing, intraplate stress field studies and modeling, apatite fission-track ther-mochronology and several geological data integration. Nevertheless, little attention has been paid to gravity and magnetic crustal studies since the publication of the po-tential field anomaly maps of the Spanish mainland. These scarce studies have focused more on the qualitative interpretation of the anomalies rather than quantitative solu-tions to concrete tectonic or structural problems. The aim of this work is to show how the processing and enhancement of previously published aeromagnetic and gravity data by classic Fourier domain transformations could b...
A total of 1.500 km of multichannel seismic reflection profiles recorded aboard B/O Hesperides us... more A total of 1.500 km of multichannel seismic reflection profiles recorded aboard B/O Hesperides using a seven gun array and a 96 channel streamer during the austral summer of 1991-1992 were used to study four structural provinces on the Antarctic and Scotia plates. These provinces which differ in structural style and crustal character include:
Un analisis detallado del relieve de la Depresion del Burguillo permite establecer su evolucion m... more Un analisis detallado del relieve de la Depresion del Burguillo permite establecer su evolucion morfogenetica reciente, asi como relacionar estas caracteristicas morfologicas con la deformacion cuaternaria. - 1. El relieve esta caracterizado por cuatro niveles de superficies, interpretadas geneticamente como desnivelaciones tectonicas a partir de una superficie fundamental. La formacion del nivel inferior se relaciona con basculamientos de la fosa hacia el sur asimilables a la fase postarcosica (Plioceno Medio-Pleistoceno basal) del esquema de PEDRAZA (1978). - 2. Los bordes de la fosa estan constituidos por fuertes escarpes de caracter tectonico, en general de direccion N. 70-80o. - 3. Labrado sobre el fondo de la fosa destaca un sistema de rellanos con perfil de glacis, causados por el encajamiento progresivo de la red fluvial y relacionados con hundimientos sucesivos de la fosa. La morfologia refleja la existencia de movimientos recientes de basculamiento de la fosa hacia el sur, continuandose la deformacion que dio lugar a la superficie inferior de la fosa y definiendo a su borde meridional como una zona de maxima deformacion.
The accommodation of the Africa-Eurasia convergence in the southern margin of the Iberian Peninsu... more The accommodation of the Africa-Eurasia convergence in the southern margin of the Iberian Peninsula can be described by the analysis of earthquakes distribution and magnitude. This analysis allows the differentiation of two segments in the plate boundary. In the Gulf of Cadiz, deep and high magnitude seismic events are localised under some submarine highs (Josephine, Gorringe, Sao Vicente and Guadalquivir) suggesting the existence of underthrusting zones connected by transfer transverse zones. The shallow and diffuse seismicity of this oceanic area would correspond to distributed deformation taken by shallow faults and related to the underthrusting of the Eurasian lithosphere. In contrast, the accomodation of the' convergence in the Alboran Sea is assumed in a zone of limited subduction, the West Alboran Subduction Zone, which is defined by the occurrence of intermediate earthquakes. In this zone, the Iberian lithosphere plunges under the weak Alboran platelet. The shallow, weak and diffuse seismicity corresponds indeed to distributed deformation. The main shocks of this segment are concentrated at depth in the contact between the strong African lithosphere and the Alboran platele
The analysis of multibeam bathymetric data and high resolution seismic profiles has allowed us to... more The analysis of multibeam bathymetric data and high resolution seismic profiles has allowed us to define the tectonic geomorphology of the Adra margin, northern Alboran Sea. Four geomorphic tectonic-related structures have been analyzed: (i) Longitudinal ridges (N50-70); (ii) Linear scarps (N30, N55, N130, N165, N-S); (iii) Tectonic depressions (N130, N165, N-S), and (iv) Lines of changes in the slope gradient (N130). In the northwestern sector morphostructure is related to a blind thrust (NE-SW), which folds Quaternary units, and in the eastern sector is linked to the NE-SW sinistral strike slip fault of La Serrata (NE-SW). Between these two structures, a NW-SE dextral strike-slip fault system, including the Adra Fault, and a NNE-SSW highly deformed corridor constituted by secondary NNW-SSE faults have been developed. Minor high angle N-S reverse faults can be related to secondary deformation features, due mainly to the interference of Chella Bank and the regional main fault systems.
RESUMEN: Las relaciones entre las capas del Ordovicico Inferior y los materiales infrayacentes ha... more RESUMEN: Las relaciones entre las capas del Ordovicico Inferior y los materiales infrayacentes han sido determinadas por primera vez mediante una cartografia detallada en el Anticlinal del Tirteafuera, extremo oriental de la zona Luso Oriental-Alcudiana, en el S. de la provincia de Ciudad Real. Teniendo en cuenta esta relacion y la analogia con otras areas vecinas, ha sido posible definir una sucesion de edad Precambrico Superior en la cual se distingue una unidad inferior compuesta por pelitas y grauvacas alternantes y una unidad superior que contiene varios niveles de conglomerados y un unico nivel carbonatado cuya cartografia se establece por primera vez. El Ordovicico Inferior ha sido dividido en un tramo de areniscas y conglomerados de edad Tremadoc y en un nivel de naturaleza cuarcitica correspondiente al Arenig. SUMMARY: By means of a detailed mapping, the relationships among the Lower Ordovician and its underlaying levels have been established in the Tirteafuera Anticline (e...
La interpretacion de una malla de perfiles sismicos de reflexion, monocanal y multicanal, ha perm... more La interpretacion de una malla de perfiles sismicos de reflexion, monocanal y multicanal, ha permitido analizar las estructuras neotectonicas en el sector central del margen septentrional del mar de Alboran. La plataforma marginal de Djibouti es un area elevada, caracterizada por la presencia de un conjunto de montes submarinos de origen tanto estructural como volcanico. Bajo esta plataforma se encuentra la Cuenca de Motril que tiene un origen extensional, si bien su geometria ha sido modificada desde el Mioceno superior. Sus bordes y su interior estan deformados mediante estructuras compresivas con el desarrollo de pliegues y estructuras de inversion de antiguas fallas normales. Ademas, se ha reconocido la presencia de fallas en direccion sinestrales de orientacion NE-SO a NNE-SSO, y destrales de tendencia NO-SE que controlan tanto la geometria actual de esta cuenca como la propia fisiografia.
Between Africa and the Iberian Peninsula the oblique convergence is assumed in an ill-defined pla... more Between Africa and the Iberian Peninsula the oblique convergence is assumed in an ill-defined plate boundary. This boundary contains four different zones corresponding to the here named as Oceanic Area, Gulf of Cadiz, Alboran Sea and Algerian Margin. West of Gibraltar, a simple-shear tectonic regime together with a strong mechanical coupling can be considered, being the deformation concentrated in several main faults. An effective transmission of the deformation occurs along the Portuguese Margin. In the Alboran Sea, the convergence is assumed by means of a pure-shear tectonic regime and the deformation is highly distributed. This central sector is characterized by a weak mechanical coupling with no effective transmission of the deformation towards the interior of the Iberian Peninsula. In the Algerian Margin, the deformation is more concentrated and a strong coupling can be considered.
Comision Interministerial de Ciencia y Tecnologia - CICYT.-- Direccion General de Investigacion C... more Comision Interministerial de Ciencia y Tecnologia - CICYT.-- Direccion General de Investigacion Cientifica y Tecnica - DGICYT.--
The spatial distribution of the drainage pattern, the subsurface flow and the maximum values of t... more The spatial distribution of the drainage pattern, the subsurface flow and the maximum values of transmisivity in the aquifer of El Campo de Montiel, as well as the localisation of the springs of the Lagunas de Ruidera, can be explained as a result of the activity of a weak intraplate compressive stress field transmitted from the Betic border
Central Iberia constitutes one of the best natural laboratories to study Alpine intraplate deform... more Central Iberia constitutes one of the best natural laboratories to study Alpine intraplate deformation of the older Variscan basement because of far field effects of plate bound-aries. During the last decade, a great effort has been made to explain the tectonic evolution of the area by different approaches such as, geological mapping and sec-tion balancing, intraplate stress field studies and modeling, apatite fission-track ther-mochronology and several geological data integration. Nevertheless, little attention has been paid to gravity and magnetic crustal studies since the publication of the po-tential field anomaly maps of the Spanish mainland. These scarce studies have focused more on the qualitative interpretation of the anomalies rather than quantitative solu-tions to concrete tectonic or structural problems. The aim of this work is to show how the processing and enhancement of previously published aeromagnetic and gravity data by classic Fourier domain transformations could b...
A total of 1.500 km of multichannel seismic reflection profiles recorded aboard B/O Hesperides us... more A total of 1.500 km of multichannel seismic reflection profiles recorded aboard B/O Hesperides using a seven gun array and a 96 channel streamer during the austral summer of 1991-1992 were used to study four structural provinces on the Antarctic and Scotia plates. These provinces which differ in structural style and crustal character include:
Un analisis detallado del relieve de la Depresion del Burguillo permite establecer su evolucion m... more Un analisis detallado del relieve de la Depresion del Burguillo permite establecer su evolucion morfogenetica reciente, asi como relacionar estas caracteristicas morfologicas con la deformacion cuaternaria. - 1. El relieve esta caracterizado por cuatro niveles de superficies, interpretadas geneticamente como desnivelaciones tectonicas a partir de una superficie fundamental. La formacion del nivel inferior se relaciona con basculamientos de la fosa hacia el sur asimilables a la fase postarcosica (Plioceno Medio-Pleistoceno basal) del esquema de PEDRAZA (1978). - 2. Los bordes de la fosa estan constituidos por fuertes escarpes de caracter tectonico, en general de direccion N. 70-80o. - 3. Labrado sobre el fondo de la fosa destaca un sistema de rellanos con perfil de glacis, causados por el encajamiento progresivo de la red fluvial y relacionados con hundimientos sucesivos de la fosa. La morfologia refleja la existencia de movimientos recientes de basculamiento de la fosa hacia el sur, continuandose la deformacion que dio lugar a la superficie inferior de la fosa y definiendo a su borde meridional como una zona de maxima deformacion.
The accommodation of the Africa-Eurasia convergence in the southern margin of the Iberian Peninsu... more The accommodation of the Africa-Eurasia convergence in the southern margin of the Iberian Peninsula can be described by the analysis of earthquakes distribution and magnitude. This analysis allows the differentiation of two segments in the plate boundary. In the Gulf of Cadiz, deep and high magnitude seismic events are localised under some submarine highs (Josephine, Gorringe, Sao Vicente and Guadalquivir) suggesting the existence of underthrusting zones connected by transfer transverse zones. The shallow and diffuse seismicity of this oceanic area would correspond to distributed deformation taken by shallow faults and related to the underthrusting of the Eurasian lithosphere. In contrast, the accomodation of the' convergence in the Alboran Sea is assumed in a zone of limited subduction, the West Alboran Subduction Zone, which is defined by the occurrence of intermediate earthquakes. In this zone, the Iberian lithosphere plunges under the weak Alboran platelet. The shallow, weak and diffuse seismicity corresponds indeed to distributed deformation. The main shocks of this segment are concentrated at depth in the contact between the strong African lithosphere and the Alboran platele
The analysis of multibeam bathymetric data and high resolution seismic profiles has allowed us to... more The analysis of multibeam bathymetric data and high resolution seismic profiles has allowed us to define the tectonic geomorphology of the Adra margin, northern Alboran Sea. Four geomorphic tectonic-related structures have been analyzed: (i) Longitudinal ridges (N50-70); (ii) Linear scarps (N30, N55, N130, N165, N-S); (iii) Tectonic depressions (N130, N165, N-S), and (iv) Lines of changes in the slope gradient (N130). In the northwestern sector morphostructure is related to a blind thrust (NE-SW), which folds Quaternary units, and in the eastern sector is linked to the NE-SW sinistral strike slip fault of La Serrata (NE-SW). Between these two structures, a NW-SE dextral strike-slip fault system, including the Adra Fault, and a NNE-SSW highly deformed corridor constituted by secondary NNW-SSE faults have been developed. Minor high angle N-S reverse faults can be related to secondary deformation features, due mainly to the interference of Chella Bank and the regional main fault systems.
RESUMEN: Las relaciones entre las capas del Ordovicico Inferior y los materiales infrayacentes ha... more RESUMEN: Las relaciones entre las capas del Ordovicico Inferior y los materiales infrayacentes han sido determinadas por primera vez mediante una cartografia detallada en el Anticlinal del Tirteafuera, extremo oriental de la zona Luso Oriental-Alcudiana, en el S. de la provincia de Ciudad Real. Teniendo en cuenta esta relacion y la analogia con otras areas vecinas, ha sido posible definir una sucesion de edad Precambrico Superior en la cual se distingue una unidad inferior compuesta por pelitas y grauvacas alternantes y una unidad superior que contiene varios niveles de conglomerados y un unico nivel carbonatado cuya cartografia se establece por primera vez. El Ordovicico Inferior ha sido dividido en un tramo de areniscas y conglomerados de edad Tremadoc y en un nivel de naturaleza cuarcitica correspondiente al Arenig. SUMMARY: By means of a detailed mapping, the relationships among the Lower Ordovician and its underlaying levels have been established in the Tirteafuera Anticline (e...
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