Geogaceta -- Nº 48, (2010)

Permanent URI for this collectionhttps://hdl.handle.net/10272/7510

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Actividad paleo-hidrotermal episódica en la Sierra de Guadarrama (Sistema Central Español): nuevas edades K-Ar y correlación tectónica con la Cordillera Ibérica
(Sociedad Geológica de España, 2010) Galindo, Carmen; Casquet Martín, César; Tornos, Fernando
Episodic hydrothermal alterations in the Sierra de Guadarrama took place between ca. 300 Ma and 10 Ma. New K-Ar ages for hydrothermal minerals have been obtained that along with previous data allow to better constrain the late- to post-Variscan history of tectono-hydrothermal activity. This activity can further be correlated with Alpine tectonic events in central Iberia recorded in Permian to Cainozoic sedimentary basins. Dating of hydrothermal events in the basement is thus a useful tool to better constrain the chronology of tectono-sedimentary events in the cover
Zonas de falla y desarrollo de cataclasitas en la Unidad del Aljibe (Complejo del Surco de los Flyschs, Béticas)
(2010) Balanyá, Juan Carlos; Expósito Ramos, Inmaculada; Crespo Blanc, Ana; Luján, María
The Aljibe Unit is the largest tectonic element within the Flysch Trough Complex in the Betics. Its structure consists of an imbricate thrust system, developed on top of the Subbetic zone mainly during Middle Miocene. Strike-slip faults and normal-component faults developed at the same time and later. The study of representative deformation bands, a few to tens meters width and associated with all the type of faults, in terms of meso- and microstructures allow us to investigate the fault kinematics and conditions during deformation. In particular, the fault zones which affected the quartzose sandstones of the Aljibe Formation, show a high concentration ofbrittle deformation structures. Together with discrete fracture surfaces, joints and veins, and asymmetric folds, the more prominent structure corresponds to cataclastic slip bands (CSBs), 1 to 5 mm thick. They are either subparalell to the main fault surface or anastomosed. Fault rocks associated with CSBs are protocataclasites and cataclasites. Within the CSBs thicker than 2 mm, a cataclastic foliation oblique to CSB walls can develop. It provides a shear sense indicator coherent with other criteria observed in the same fault zone
Tratamiento pasivo con un sustrato alcalino disperso de drenajes ácidos de mina con alta carga metálica en la cuenca del río Odiel (Faja Pirítica Ibérica, SO España)
(2010) Caraballo Monge, Manuel Antonio; Macías Suárez, Francisco; Rötting, Tobías S.; Nieto Liñán, José Miguel; Ayora Ibáñez, Carlos
Many of the passive treatment systems treating acid mine drainage (AMD) have been focused on treating AMD with low to very low metal concentration as those existing, for instance, at coal mining districts. However all these passive treatment systems show severe problems of clogging or reactivity loss when exposed to AMD with high metal concentrations. To overcome all these problems we have developed a novel Dispersed Alkaline Substrate (DAS) consisting of a mixture of wood shavings (coarse inert matrix increasing hydraulic conductivity) and an alkaline reactive substrate (fine-grained limestone to raise pH and generate alkalinity). This system was under operation for a period of 20 months treating a mean inflow of 0.5 L/s. The system removed a mean net acidity of 1500 mg/L as CaC03 from the inflow water and achieved a relative removal of 100% Al, As, Cu, Pb, Cd and V, 40% Te and 15% S042-. Total removal in the reactive tank was in the range of 7.1 tonnes Te, 6.9 tonnes S042-, 2.7 tonnes Al, 0.6 tonnes Si, 0.1 tonnes Zn and 0.3 tonnes Cu
Tortugas del Cretácico Inferior (Hauteriviense-Barremiense) de La Rioja (Cuenca de Cameros, España)
(2010) Pérez García, Adán; Murelaga, Xabier; Torres, José Ángel; Viera, Luis Ignacio; Sáez Benito, Francisco Ramón
The information about the turtles from the Early Cretaceous of the Iberian Peninsula is, until now, very poor. We describe here three specimens found in the Lower Cretaceous (Hauterivian-Barremian) of La Rioja, of at least two different taxa, being one of them Salasemys pulcherrima. This study provides new data on the representatives ofthe Spanish Fucryptodiran turtles
The influence of plagioclase LPO on P-wave anisotropy and seismic reflectivity of metabasites from the lower continental crust
(2010) Díaz Azpiroz, Manuel; Lloyd, Geoffrey E.
En este trabajo se han obtenido valores de velocidad y anisotropía de ondas-P, con distintas proporciones hornblenda-plagioclasa, en muestras generadas a partir de anfibolitas naturales, en las que una única orientación cristalográfica preferente (OCP) de hornblenda se combina con distintas OCPs de plagioclasas. Los resultados sugieren que, aunque las propiedades sísmicas de la corteza inferior están controladas principalmente por la OCP de hornblenda, la plagioclasa, incluso apareciendo en proporciones bajas, puede modificar dicho comportamiento. Su grado de influencia depende de la intensidad y la orientación de la OCP. Así, variaciones en la OCP de plagioclasas pueden producir modificaciones en la magnitud, la distribución espacial y la anisotropía de Vp, lo que podría tener efectos en la reflectividad de la corteza continental inferior
Tectónica reciente en la cuenca de Ouarzazate (Atlas marroquí): Tasas de acortamiento y levantamiento tectónico a partir de los marcadores cuaternarios
(2010) Pastor, Àlvar; Teixell, Antonio; Arboleya, María Luisa
Recent studies have shown that the uplift of the moroccan Atlas Mountains resulted from a combination of crustal shortening and mantle thermal processes. Within this framework, to gain insight of the dynamics of these processes in recent times, we have investigated the nature and rates of Quaternary deformation in a case field area, which contains the best dated record of fan and terrace deposits, and a moderate seismicity. The area selected is the northern Ouarzazate basin, at the southern orogenic front ofthe Atlas, where folds and thrusts involve a sequence of stepped terraces where recently obtained Terrestrial Cosmogenic Nuclide surface exposure ages provide a basis to calculate shortening rates for the last —250 ky (since the interglacial peak MIS-9c). Calculated Quaternary shortening rates for individual thrust structures range between 0.13-0.21 mmfy, which are greater that the average for these structures since Miocene times, but not very different from the total shortening rate estimated for the southern Atlas front since then (0.3 mmfy). Seismic reflection profiles show two tectonic styles acting simultaneously within the northern Ouarzazate basin: thick-skinned to the west and thin-skinned to the east. This difference is also reflected on the deformation geometry ofthe Quaternary markers
Sobre el origen y edad de la depresión del Jiloca (Teruel, Cordillera Ibérica centro-oriental)
(2010) Simón Gómez, José Luis; Rubio, José Carlos; Soriano, María Asunción
The relative role ofextensional tectonics and erosional lowering in the evolution of the Jiloca depression has been debated. The classic notion of a Pliocene, NNW-SSE trending graben is discussed by a number of authors; they enhance the role of differential erosion, based on the supposed identification of either numerous nested Paleogene-Early Miocene pediplains, or suballuvial Plio-Quaternary karstic surfaces. Nevertheless, the geometry of the sedimentary infilling (up to 100 m thick, controlled by the NW-SE master faults) and the evidence of tectonic offset at the Calamocha and Concud faults (160-180 m and 250 m, respectively) supports its tectonic origin
Sedimentología y geomorfología del fondo de un canal mareal asociado a la desembocadura del río Guadiana: «La Ría Carreras» (Huelva, SO España)
(2010) Morales González, Juan Antonio; Lozano Guerra-Librero, Claudio; Cantano Martín, Mercedes; Rodríguez Ramírez, Antonio; Delgado Rodríguez, Irene
The present paper characterizes the distribution of sediments and geo-forms in a tidal channel within the Guadiana River Mouth using Side Scan Sonar techniques. This work presents a map of bed distribution in terms of sedimentary lithology and geomorphological features. Trom a Hthological point of view clean sands, muddy sands and sandy muds can be distinguished. Trom a dynamic perspective, each Hthological type can present accumulative or erosional features. The dominant flow regime in the sandy beds can be deduced from the morphology and asymmetry ofbedforms
Role of sea-level change and syn-sedimentary extensional Tectonics on Ladinian-Carnian Alpujarride carbonates (Alpujarride Complex, Betic Internal Zone, SE Spain)
(2010) Martín Rojas, Iván; Somma, Roberta; Delgado, Francisco; Estévez, Antonio; lannace, Alessandro; Perrone, Vincenzo; Zamparelli, Valeria
En este trabajo se estudia el efecto de la acción combinada de los cambios del nivel del mar y la tectónica sinsedimentaria extensional en la formación Meta-carbonatada de la unidad de Gádor-Turón (Complejo Alpujárride, Cordillera Bética). Nuestro análisis apunta a que la parte inferior de la formación se depositó en una rampa carbonatada (miembros 1-4), con ausencia de actividad tectónica significativa. La parte superior de la formación (miembros 5-6) se originó en una plataforma carbonatada limitada por fallas y en un contexto en el que se alternaban momentos de actividad tectónica extensional con momentos de calma. El cambio de modelo de plataforma registrada en el miembro 5, tuvo lugar durante el Ladiniense- Carniense, simultáneamente con un momento de gran actividad tectónica extensional. Los datos obtenidos parecen señalar que el depósito de los distintos miembros estaba controlada por los cambios del nivel del mar. Al descender a una escala de observación más detallada, la organización en intervalos y asociaciones de facies dentro del miembro 5 registran varias para-secuencias aparentemente relacionadas con la tectónica sinsedimentaria
Relación entre la evolución geomorfológica y el uso humano de las zonas costeras: Ejemplo de Isla Cristina (Huelva, SO España)
(2010) Morales González, Juan Antonio; Cantano Martín, Mercedes; Rodríguez Ramírez, Antonio
This work studies the recentmost evolution of /s/a Cristina as a consequence of the human changes occurred in the environment, mainly related to harbour structures and urban building. The natural evolution, previous to an intensive human influence, consisted of a primary longitudinal accretion of a barrier island limited by two tidal channels. This primary construction was followed by a progradation process occurred in relation with the evolution of an ebb-tidal delta located in front of the western inlet. The construction of two jetties to stabilize this inlet modified the pattern ofwave action inducing the last stage ofprogradation. An extensive urbanization around the original town modified the tidal drainage and signified the transformation ofaeolian dune fields and salt marshes in new urban areas
Propuesta de estructura geológica para el depósito gigante de sulfuros masivos volcanogénicos de Río Tinto, Faja Pirítica Ibérica
(2010) González Clavijo, Emilio J.; Díez Montes, Alejandro
New field reconnaissance around the Río Tinto Mine led to a better structural knowledge on the area. The improved map support a different geological evolution on this sector determined by an earlier extensional event, which probably conditioned the mineralization processes. Later compressive poly-cyclic Variscan events developed thin-skinned tectonics
Preservación excepcional de un disco intervertebral atribuido a un reptil marino, descubierto en la Sierra de Albarracín (Cordillera Ibérica, España) en el siglo XIX
(2010) Pérez García, Adán; Gaseó, Francisco
An element that is part of the collection of vertebrate paleontology of the MNCN since before the Spanish Civil War is described. The specimen was found in the Jurassic of the Sierra de Albarracín, in the Iberian Range, and is interpreted as an intervertebral disc with exceptional preservation. This specimen is attributed to a marine reptile. We discuss its possible systematic assignation
Paleosuelos con calcretas, rizolitos y Microcodium en ambientes fluviales y aluviales (Oligoceno, Prebético, provincia de Murcia)
(2010) Molina, José Miguel; Nieto, Luis M.
The Oligocene of the Prebetic in the Jumilla-Yecla area is mainly represented by fluvial and alluvial sediments. The elementary sequence observed in these materials is made up by conglomerates, sandstones and marlstones. Intercalated in this sequence continental carbonates appear. These carbonates are characterized by the presence of rhizoliths, laminar calcretes, glaebular or nodular textures and Microcodium. These carbonates are interpreted as calcretes and their features show the great importance of the vegetation in the pedogenic origin. Then, they could be the consequence of a warm to hot climates and low, seasonal rainfall conditions
Origen de la salinidad de las aguas subterráneas del sistema acuífero costero de Torrevieja: Aspectos Hidroquímicos
(2010) Gómez Fontalva, José Manuel; Calvache Quesada, María Luisa; Duque, Carlos
The aquifer system of Torrevieja (SE Spain) is under a process of seawater intrusion. However, there are uncertainties about the origin of abnormally high salinity values detected in boreholes located 15 km from the coastline. Also there are two hypersaline lagoons over the aquifer that could be related to groundwater. The salinity sources have been determined with hydrochemical ana/ys/s of groundwater, electric conductivity logs, major-minor ions relationships and hydrochemical indexes rNa/rCI, rNa/rK, rSOJ rCI, rS04andrCa. In this paper we propose an interpretation for the salinity differences and the relation between the lagoons and the aquifer
Nuevos yacimientos de icnitas domerienses en Ibaqalliwn (Alt Bou Guemez, Alto Atlas Central. Marruecos)
(2010) Boutakiout, Mohamed; Masrour, Moussa; Ladel, Latifa; Díaz Martínez, Ignacio; Pérez Lorente, Félix
During the 2009's summer courses (universities Rabat-La Rioja) 6 new paleoichnological sites are found in the Bou Guemez river. The previously know Ibaqalliwn-Talsnant sites are located in the close west. All new, and Ibaqualliwn-Talsnant fossil traces, are print over the upper levels of marine limestones from Arganane Formation (Domerian). The likewise Domerian lowermost part continental sediments of the superposed Azilal Formation is placed to 5 m above the ichnites. The Utological composition, invertebrate fossil content, and number ofichnological levels is similar in the AssifAit-n-Bou Cuemez-Assif-n-Rbat zone. In spite ofthe Quaternary aluvial sediments cover, the geological properties are enough to define exactly the same stratigraphic position of the sites. The Arganane Formation dissapear to east part and the new sites are the east end ofthe Bou Guemez dinosaur footprints outcrops. It is important show the sauropod supremacy in the Bou Guemez zone
Nuevas aportaciones a la caracterización geomorfológica del Manto Eólico Litoral de El Abalario-Doñana: el perfil de la laguna Río Loro (Huelva, España)
(2010) Díaz del Olmo, Fernando; Recio Espejo, José Manuel; Borja Barrera, César; Cámara Artigas, Rafael; Borja Barrera, Francisco
The RLO-ZC profile of Río Loro small lake at El Abalarlo area in MELAD (Aeolian Littoral Sand Sheet at El Abalario-Doñana), in Doñana Natural Park (Huelva, Spain) has been studied from a weathering point of view. We can identify two units in this profile: the below of these constitutes one sandy-clayey removed deposit from Pleistocene, where quartz is predominating in sands and kaolinites in the clay minerals. The superior unit is a sandy-clayey deposit ofaeolian and pooled character from Pleisto-Holocene or Holocene with quartz, high level smectite content and low level kaolinite proportion. Finally, the study provides a new interpretation to the geomorphologic model of MELAD in El Abalario area
Multiproxy approach to characterize an overwash deposit: Oualidia lagoon (Moroccan Atlantic coast)
(2010) Leorri, Eduardo; Conceipáo Freitas, M.; Zourarah, Bendahhou; Andrade, César; Mellas, Samira; Cruces, Anabela; Griboulard, Roger; Lopes, Vera
Se han analizado muestras sedimentologicas y micropaleontologicas de un sondeo realizado en el extremo sur oeste de la laguna costera de Oualidia (Marruecos). Los resultados obtenidos muestran una secuencia de relleno que presenta una evolución desde materiales submareales con influencia marina hasta que la zona se colmata y aparece un medio marismeño. La zona intermedia de la secuencia presenta materiales arenosos con influencia marina que se hacen mas restringidos, como indica el predominio de materiales fangosos y foraminíferos típicos de ambientes salobres. Esta secuencia está truncada en el techo por la presencia de un deposito de overwash. Mientras que este depósito pueda diferenciarse netamente de los materiales infrayacentes, es imposible concluir que esta combinación de técnicas pueda utilizarse para identificar depósitos de tormenta en el registro fósil. Los resultados obtenidos, sugieren, sin embargo, que este tipo de depósitos podrían diferenciarse en secuencias continuas de depósitos marismeños y por tanto podrían proporcionar información relevante de la frecuencia e intensidad de tormentas ocurridas en el pasado. Esos estudios han de tener en cuenta, sin embargo, otros aspectos sindeposicionales, como son la bioturbación o la preservación de las capas sedimentarias
Movilidad de contaminantes en fosfoyesos de la industria de fertilizantes de Huelva (SO España)
(2010) Santisteban Fernández, María; Pérez López, Rafael; Nieto Liñán, José Miguel
The dynamic of trace elements from phosphate rock ore to the environment in a phosphoric acid plant located in SW Spain and the impact of phosphogypsum wastes were investigated through total digestion and BCR-sequential extraction. Based on those concentrations that are likely to be most readily mobile in the environment, phosphogypsum acts as a higher emission source of contaminants than the original rock. About 100 million tonnes of phosphogypsum are stack-piled in a dump of 1200 ha over salt- marshes of an estuary formed by the confluence of the Tinto and Odiel rivers. Phosphogypsum capacity as a source ofmobile contaminants in three environmentalscenarios (water leaching, exposure to oxidising and reducing conditions) was quantified by combining sequential extraction and waste mass. The amounts of mobile contaminants that could be released for every tonne of phosphogypsum are approximately 7-102 gSr, 1.1-102 gTe, 55 gY, 30 gCe, 12gCr, 11 gTi, 5 gZn, 4 g each of Cu and Pb, 3 g each of V and Cd, 2 g each of As and Ni, and 1 gU. Multiplying these amounts by 100 Mt, it is possible to calculate risk assessments of phosphogypsum for estuarine zones
Modelización hidrológica de las cuencas de los ríos Múrtigas y Caliente (Huelva, España). Calidad de los datos de aforos
(2010) Galván González, Laura; Olías Álvarez, Manuel
Hydrological modeling of the Odiel River by means of th SWAT program (Soil and Water Assessment Tool) revealed a need for stream-gauge stations in the northern part ofthe basin. This is because materials with different hydrological behaviour from those of the rest of the basin outcrop in this area. Tor that reason this work develops a model of the Múrtigas and Caliente River catchments located adjacent to the north of Odiel basin and with similar hydrological characteristics. The monthly values of the NST (Nash and Sutcliffe Efficiency) obtained for the validation period are -0.73 for the Múrtigas River and 0.73 for the Caliente River. The reason for these low values is that the data from stream-flow measurements are often inaccurate. The data quality is especially poor in the Múrtigas River stream-gauge station, which is currently the only in operation. Due to the necessity of accurate data for the calibration ofthe hydrological models, and the fact that the data quality obtained from the stream-flow measurements in the Múrtigas and Caliente river stations is very low, it is not possible to calibrate properly the model. It is, therefore, argued that the reliability ofstream-gauge stations in this area must be improved
La tomografía eléctrica aplicada a la investigación del yacimiento arqueológico de Cástulo (Linares, Jaén). Resultados preliminares
(2010) Rey Arrans, Javier; Martínez López, Julián; Dueñas, José; Campos, Daniel; Arias, Francisco; Benavente Herrera, José
The Cástulo archaeological site is one of the most important ofthejaen province. Despite its significance, the excavation work has been scarce. Site development for cultural purposes requires, firstly, a detailed, non-destructive analysis, where the most interesting zones are identified. We have used geophysical techniques to attempt this. In a preliminary campaign, 5 electrical tomography profiles -each one with a length of 32 m- have been carried out. In every profiles we have used different electrode configurations (Dipole-Dipole, Wenner-Schlumberger and Wenner), as well as two inter-electrode spacing: 0.5 and 1 m. The aim was to test the geo-electrical response of the possible buried structures, and the best shallow results have been obtained with the Dipole-Dipole. This study has allowed us to identify what it was supposed to be the rests of a wall of an probably ancient church of this Iberian-roman town, which finally has been confirmed by way of an archaeological excavation campaign carried out in the summer of2009

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