Geogaceta -- Nº 49, (2010)

Permanent URI for this collectionhttps://hdl.handle.net/10272/7454

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Variaciones de color y contenido de CaCO3 en los pares margacaliza del Maastrichtiense superior y Eoceno inferior en Sopelana (Arco Vasco): reflejo de cambios paleoambientales
(Universidad de Huelva, 2010) Iridoy, Peru; Zudaire, Saioa; Azaguirre, Maddi; Dorronsoro, Ane; Olano, Galder; Beriain, Eneko; Usarbarrena, Ariane; Elorza, Javier
The Sopelana sea-cliff exposes marl-limestone couplets from the Upper Maastrichtian (MS1 and MS2 sections) and the Lower Eocene (EI section), in the deep Basque Arc domain. The high-resolution analysis (% CaCO3) of the MS1 couplets confirms a complex behaviour with strong compositional contrast vs. a more regular MS2 couplets. This may be due to a drastic environmental change (long humid and rainy alternating to drier periods) towards dominant humid and rainy periods, with a minor seasonal nature and high sedimentation rate (72 cm/20 ky). The deep, cold, oxygenated marine water produces a change of coloration (grey to purple) during the sedimentation, in the Upper Maastrichtian couplets before diagenesis activity. It is the beginning of the Cretaceous oceanic red beds (CORB´s)
Un ejemplo de llanura fluvio-deltaica influenciada por las mareas: el yacimiento de icnitas de Serrantes (Grupo Oncala, Berriasiense, Cuenca de Cameros, N. de España)
(Universidad de Huelva, 2010) Quijada, Isabel Emma; Suárez González, Pablo; Benito, María Isabel; Mas, José Ramón; Alonso, Ángela
The Late Jurassic-Early Cretaceous Cameros Basin comprises an expanded Tithonian to Early Albian stratigraphic record, mainly made up of fluvial and lacustrine systems, but also containing minor marine incursions. This basin is renowned because of preserving numerous ichnites sites, being the Berriasian Oncala Group one of the units that includes more of them. A sedimentological study of the deposits at the Serrantes site demonstrates that the ichnites are clearly associated with tidally-influenced fluvial-deltaic meandering channel and overbank deposits. The facies appearing in this outcrop are: 1) channelized beds, 2) lutites, 3) tabular sandstone beds, 4) black limestones, 5) laminated limestones with gypsum pseudomorphs. The ichnites are clearly associated to the siliciclastic deposits, especially to the lutitic facies, and are absent in the carbonate-evaporitic deposits
The lamprophyric sub-vertical dyke swarm from Aiguablava (Catalonian Coastal Ranges): petrology and composition
(Universidad de Huelva, 2010) Ubide, Teresa; Lago San José, Marceliano; Arranz, Enrique; Galé, Carlos; Larrea, Patricia
En este trabajo presentamos un estudio petrológico detallado de algunos de los diques de lamprófido sub-verticales de edad Pérmica del complejo intrusivo de Aiguablava (Cadenas Costero Catalanas). Aportamos nuevos datos composicionales, tanto en minerales (elementos mayores) como en roca total (elementos mayores y traza), de algunos de los diques más inalterados. Del estudio realizado se deduce que todos los magmas lamprofídicos estudiados tienen un origen común, si bien presentan un pequeño rango de fraccionamiento, en el que diferenciamos tres etapas relacionadas con tres pulsos magmáticos. Según nuestros datos, algunos de los diques considerados anteriormente como espesartitas de afinidad calco-alcalina podrían tener una afinidad transicional (de subalcalina a alcalina)
Terrazas recifales en el litoral de Puerto Plata (Costa Norte, República Dominicana)
(Universidad de Huelva, 2010) Morales González, Juan Antonio; Romero Valiente, Juan Manuel
The North Coast of Dominican Republic is a tectonically rising coast drained by short rivers, with a mean wave height of 1.5 m and microtidal tides .This coast develops an active reef flat bordering sandy beaches and other deeper reef terraces. These terraces are located 5 and 15 meters deep and are separated by high dip slopes with small chanyons bioclastic sandy aprons. The present paper characterizes the reef terraces located in front of Puerto Plata coast from a morphosedimentary point of view. The active flat displays live and dead coral reefs and wide Phanerogam prairies, whereas the deep reef terraces are mainly constituted by a calcirrudite of bioclastic coral fragments whitout living corals
Sobre el origen de la asimetría en el patrón general del relieve en el interior de la Península Ibérica: nuevos resultados obtenidos mediante modelación análoga
(Universidad de Huelva, 2010) Fernández Lozano, Javier; Sokoutis, Dimitrios; Willingshofer, Ernst; Muñoz Martín, Alfonso; Vicente, Gerardo de; Cloetingh, Sierd
Analogue modelling contributes to the interpretation of lithosphere scale folds in Iberia as a result of largescale convergence during Oligocene-Miocene times between the Iberian and European Plates. Different tectonothermal events affected the microplate since late Paleozoic and resulted in lateral strength variations of the Iberian lithosphere. An old and cold lithosphere, Variscan in age, can be found in the westernmost part of Iberia whereas a relative weak and hot Mesozoic lithosphere affected by episodes of rifting and basin inversion during Mesozoic- Tertiary times covers the area of the Iberian Chain. Our study aims at deciphering whether deformation and topography evolution in Iberia are related to lateral strength variations and/or the inherited structural grain stemming from Variscan deformation. We also have studied the strength of the lithosphere to gain insights into the effects of rheological variations related to local thrusting or primary strength variations along the Iberian lithosphere
Significado de fábricas magnéticas en rocas volcánicas cuaternarias de la Isla Decepción (Shetland del Sur, Antártida)
(Universidad de Huelva, 2010) Gil Imaz, Andrés; Gil Peña, Inmaculada; Galindo Zaldívar, Jesús; Rey Salgado, Jorge; Maestro González, Adolfo; Pueyo Anchuela, Óscar; Soto Marín, Ruth; Oliva Urcia, Belén; López Martínez, Jerónimo
This work deals with the magnetic fabric (AMS technique) of different lithotypes related to quaternary volcanism of Deception Island (South Shetland Islands). The studied rocks include lava flows from basaltic to basaltic-andesitic composition, mafic dykes and several types of pyroclastic deposits. By combining the analysis of parametric aspects of the magnetic ellipsoids and their directional pattern, four types of magnetic fabrics have been recognized. Type I fabrics are related to laminar magma flow in both lava flows and dykes. The second one is related to magma reology in lava flow and tractive streams in pyroclastic deposits. Type III only identified in dikes, characterizes the imbrications of the magma flow against the dyke wall. Type IV reflects an isotropic rock-fabric and has been related to the presence of large anisotropic grains in lavas and particle fall without later modifications in pyroclastic deposits. The obtained results demonstrate the utility of AMS technique for petrogenetic model development linked to rock-fabric acquisition
Presencia de Teredolites Leymerie 1842 en el yacimiento con dinosaurios ANA (Cretácico Inferior, Cinctorres, Castellón)
(Universidad de Huelva, 2010) Poza, Begoña; Santos Cubedo, Andrés; Santisteban, Carlos de; Suñer, Maite
The ANA fossil site (Cinctorres, Castellón) is placed in the Arcillas de Morella Formation (early Aptian, Lower Cretaceous) of the Maestrat basin. Dinosaur fossils were recovered in it. The Arcillas de Morella Formation in the sector of Cinctorres has 57 meters of thickness. It is formed by six facies organized in a minimum of twelve parasequences in four depositional sequences. Three of these sequences include incised valleys. The ANA fossil site is located in the infill of the third incised valley. Here, several tree trunks have been recovered in those the ichnospecie Teredolites clavatus Leymerie, 1842 has been identified. This ichnogenus is indicative of open marine and marginal marine environments. Its presence in different levels of the Arcillas de Morella Formation (Teulería Milian, Mas de la Parreta quarry and ANA) allows us to identify only periods of transgression. It would not correlate the series, neither would be an indication of the lateral extent of the deposits with bored logs
Paleobiogeografía y correlaciones bioestratigráficas intercontinentales con carofitas cretácicas y macroforaminíferos paleocenos
(Universidad de Huelva, 2010) Martín Closas, Carles; Serra Kiel, Josep; Ferràndez Cañadell, Carles; Villalba Breva, Sheila; Gallardo, Alejandro; Tosquella Angrill, Josep
Cretaceous charophytes and Palaeocene larger foraminifera are facies-linked microfossils used to perform biostratigraphic correlation between distant basins, in Eurasia (charophytes) or the whole Tethys (larger foraminifera). The capability of these organisms for dispersal and colonization is analysed and appears to be dependent both on palaeoecological and palaeobiological factors. During the Cretaceous of the Northern hemisphere, Clavatoracean charophytes include five cosmopolitan or subcosmopolitan species. They display a generalistic range of habitats (from fluvial siliciclastic to alkaline lacustrine and brackish) and conjoint gametangia (monoecious) allowing them to colonize effectively new sites and disperse. Palaeocene Tethyan larger foraminifera that show a large distribution live in the deeper parts of shallow platforms, a habitat where the taxonomic diversity within the group is low. Significant for the long range geographic expansion of larger foraminifera is the possibility to catch planktonic algae to establish the species-specific endosymbiosis that characterize the group. In spite of being so different, both case-studies suggest that there are common patterns of biogeographic behaviour of this kind of facies-linked microfossils, which could lead to propose a model of biogeographic constraints in long distance biostratigraphic correlation
Nuevas aportaciones sobre la influencia marina y la edad de los carbonatos de la Fm Leza en el sector de Préjano (SE de LaRioja). Cretácico Inferior, Cuenca de Cameros
(Universidad de Huelva, 2010) Suárez González, Pablo; Quijada, Isabel Emma; Mas, José Ramón; Benito, María Isabel
The Cameros Basin is a rift basin whose sedimentary infill is essentially continental with some episodes of marine influence. The Leza Fm carbonates (Enciso Gr, Barremian-Aptian) correspond to one of these episodes and their depositional environment has been described as lacustrine with occasional marine incursions. A detailed facies analysis of these carbonates in the Préjano area has led to the conclusion that the depositional environment of the Leza Fm in this area is in fact a system of coastal-lakes filled with brackish water as shown by the abundance of marine microfossils (Dasycladales algae and foraminifera) coexisting with continental microfossils (charophytes). The age of the Dasycladales found in the studied area is Barremian-Albian and thus it confirms the Barremian-Aptian age proposed for the Leza Fm and the Enciso Gr
Las tobas cuaternarias del río Añamaza (provincia de Soria, Cordillera Ibérica): aproximación cronológica
(Universidad de Huelva, 2010) Arenas Abad, Concepción; Sancho, Carlos; Vázquez Urbez, Marta; Pardo, Gonzalo; Hellstrom, John; Ortiz, José Eugenio; Torres, Trinidad de; Osácar, María Cinta; Auqué Sánz, Luis
High-gradient, stepped fluvial tufa systems with dammed areas existed in the River Añamaza valley (NW Iberian Ranges, Spain) during Quaternary times. Single deposits range from a few meters to about 70 m thick, in which prograding-aggrading wedges separated by erosional surfaces exist. Several episodes of tufa formation have been distinguished by means of U-series, Amino-acid racemization and radiocarbon techniques. These correlate to MIS 8, 7, 5 and 1. The presence of MIS 9 is uncertain, as chronological data may also correspond to older stages. Most tufas in this area formed in MIS 5. Distinct tufa episodes can also be distinguished in the Holocene. These are the first chronological data presented for one of the northernmost Quaternary tufa systems in the Iberian Ranges
Hydraulic brecciation on top of the Alboran Domain and its relationship with Lower Miocene deposits (Western Betics)
(Universidad de Huelva, 2010) Suades, Enric; Crespo Blanc, Ana
Al oeste de las Cordilleras Béticas, se describen unos cuerpos de brechas dentro del Complejo Maláguide, muy similares a las brechas del Mioceno inferior del grupo Viñuela. La distribución, geometría interna y características petrográficas de dichos cuerpos muestran que pueden haberse formado durante procesos cataclásticos acompañados por fracturación hidráulica. Se sugiere que estos cuerpos de brechas tectónicas nutren las brechas sedimentarias del grupo Viñuela
Geochemical evolution of the Panamanian Cretaceous-Paleogene volcanic arc: Insights from the Azuero Peninsula, SW Panama
(Universidad de Huelva, 2010) Corral, Isaac; Griera, Albert; Gómez Gras, David; Corbella, Mercè; Cardellach, Esteve
La evolución geológica de Panamá está directamente relacionada con la subducción de la placa de Nazca bajo la placa Caribeña durante el Cretácico-Paleógeno, desarrollando un arco volcánico en el margen occidental de ésta. Nos centraremos en la tectonoestratigrafía y geoquímica del arco Cretácico- Paleógeno panameño, presentando nuevos datos geoquímicos obtenidos a lo largo de todo el arco, permitiéndonos inferir la evolución geoquímmica del arco volcánico en esta zona. Se han diferenciado cuatro grandes unidades: (1)Basamento Ígneo de Azuero (BIA), (2)Proto-arco de Azuero (PAA), (3)Arco Volcánico de Azuero (AVA) y (4)Formación Tonosí. El BIA es de carácter toleítico, con una alta relación en (Nb/La) y baja en (La/Sm). Se caracteriza por una tendencia compatible con afinidad de plateau oceánico. El PAA es similar al BIA, carácter toleítico pero para el mismo contenido de (La/Sm) presenta menor (Nb/ La). La afinidad sigue siendo de plateau, enriquecida en Ba y empobrecida en Nb y Ti. El AVA es de carácter calco-alcalino, con valores bajos de (Nb/La) y altos en (La/Sm). Su afinidad es de arco volcánico. Esto sugiere una evolución del arco panameño desde el Cretácico hasta el Paleógeno desde un magmatismo de plateau oceánico (AIB) inicialmente hasta un magmatismo de arco volcánico (AVA) en los estadios finales, con estadios intermedios transicionales correspondientes al Proto-arco de Azuero (PAA)
Foraminíferos del tránsito Cenomaniense-Turoniense en la sección de El Chorro, Cordillera Bética, sur de España
(Universidad de Huelva, 2010) Sánchez Quiñónez, Carlos Alberto; Alegret, Laia; Aguado, Roque; Delgado Huertas, Antonio; Cruz Larrasoaña, Juan; Martín Algarra, Agustín; O´Dogherty, Luis; Molina, Eustoquio
A climatic, geological and biological global event resulted in sedimentation of black shales at the Cenomanian/Turonian (C/T) boundary, coinciding with the Oceanic Anoxic Event 2 (OAE2) or Bonarelli Event. We present an interdisciplinary analysis of the C/T transition at the Spanish El Chorro section (Betic Cordillera), and show the results of studies on planktic and benthic foraminifera, calcareous nannoplankton, radiolaria and environmental magnetic properties. The planktic foraminiferal biozones Rotalipora cushmani, Whiteinella archaeocretacea and Helvetoglobotruncana helvetica and the calcareous nannoplankton biozones NC11, NC12 and NC13 have been recognized. Diversity of the radiolarian assemblages gradually decreases from the upper Cenomanian towards the middle part of the OAE2 interval, where it reaches the lowest values, recovering above the OAE2. Oxygenation of the sea-bottom waters decreased towards the late Cenomanian, as inferred from a decrease in species size of benthic foraminifera 40 cm below the OAE2. Assemblages from the upper part of the section contain abundant and tiny epifaunal, trochospiral species and representatives of Tappanina, Pleurostomella and small buliminids. These data indicate that low oxygen conditions persisted towards the top of the section, 370 cm above the top of the OAE2 black shales
Evolución paleoambiental del tránsito Eoceno-Oligoceno en el Atlántico sur (Sondeo 1263) basada en foraminíferos bentónicos
(Universidad de Huelva, 2010) Fenero, Raquel; Thomas, Ellen; Alegret, Laia; Molina, Eustoquio
Quantitative análisis of benthic foraminiferal assemblages at South Atlantic Site 1263 provided information about paleobathymetry and changes in benthic foraminiferal faunas across the Eocene-Oligocene boundary. Benthic foraminifera indicate an upper abyssal depth (~ 2000 m). Changes in relative abundances of Epistominella exigua, Epistominella vitrea, Globocassidulina subglobosa and Nuttallides umbonifera, probably indicate variability in seasonality of export productivity, bottom current intensity and carbonate corrosivity. The transition into glaciation event Oi-1 is characterized by highly seasonal productivity, Oi-1 itself by less variability, probably at fairly active bottom currents
Evolución diagenética en el sector occidental de la Falla del Vallès-Penedès (Cadenas Costero Catalanas)
(Universidad de Huelva, 2010) Baqués, Vinyet; Travé i Herrero, Anna; Cantarero, Irene
From the study of the fracturing, fault rocks, petrology and geochemistry of carbonate cements were established the relative chronology of the different episodes of fracturing and the role of fluids during deformation in the western sector of the Vallès-Penedès Fault. Were recognized different types of fluids and hydraulic regimes during the development of the fault. Thus, during the early stages of fracturing attributed to Paleogene compression, fluids were highly interacted with the host-rock. By contrast, cements that fill the fractures related to the latest stages of deformation have low interaction with the host-rock and can be attributed to: 1) meteoric fluids circulated through the fractures during the latest stages of Paleogene compression or 2) the compressional fractures remained open and were subsequently sealed by cements precipitated from meteoric water. On the other hand, the later stages of fracturing attributed to Neogene extension, the hydrogeological system was opened to the meteoric waters and there was not interacted with the host-rock
Evidencias del desequilibrio y la reorganización de la red fluvial en la cuenca de Ouarzazate (Marruecos)
(Universidad de Huelva, 2010) Pastor, Àlvar; Babault, Julien; Teixell, Antonio; Arboleya, María Luisa
Since it became externally drained, the fluvial dynamics of the Ouarzazate foreland basin has been dominated by erosive processes due to a base level fall. The basin landscape is dominated by extensive Quaternary deposits aggraded by the transverse rivers draining the High Atlas Mountains. These deposits accumulated in valleys and pediments incised in the basin Tertiary infill, characterized mostly by fine-grained and soft sediments. Evidences of fluvial captures are abundant in recent times and throughout the Quaternary, in a scenario where there is more incision efficiency in the interfluves’ secondary streams (characterized by fine-grained or sediment-free pediments) than in the main transverse rivers (characterized by thick gravel deposits). Satellite imagery, elevation data and field observations demonstrate how minor streams increase their catchment areas by headward erosion, creating extensive pediments lying under the main rivers and producing captures of the main rivers. This study demonstrates the unsteady-state of the drainage network of the Ouarzazate basin and its recent reorganization, apparently uncoupled from tectonic or climatic processes
Evaluación del grado de diagénesis en huesos fósiles mediante espectroscopía de infrarrojos
(Universidad de Huelva, 2010) Castaños, Jone; Murelaga, Xabier; Castellanos, Idoia; Alonso Olazabal, Ainhoa; Zuluaga, María Cruz; Ortega, Luis Ángel
In this paper the fossil bone conservation and the diagenetic changes are studied by infrared spectroscopy (FTIR). Several parameters that describe crystallographic and chemical composition of the bone are used. The possible differences in the behavior of the bones to the diagenesis having its origin in the age of the animal or its taxonomy (red deer, bison, reindeer, wildpig) are discussed. Some samples have incorporated in its structure secondary phases (calcite) that may be removed by rinsing acid but not in all the cases. It notes that some diagenetic parameters values vary with the age of the individual but not with taxonomic differences. Most of the changes are related to the loss of collagen
El glaciar de Cuerpo de Hombre (Sierra de Béjar, Sistema Central Español) durante la deglaciación: génesis primaria del till supraglaciar de Los Hermanitos
(Universidad de Huelva, 2010) Carrasco González, Rosa María; Pedraza Gilsanz, Javier; Sanz, Miguel A.; Domínguez Villar, David; Willenbring, Jane
During the period of deglaciation of the last glacial cycle, a rock avalanche tooks place in the cliffs of Los Hermanitos (Cuerpo de Hombre Valley, Sierra de Béjar). The material displaced during the avalanche fells over the ice, was transported towards the glacier front and later on deposited as a supraglacial meltout till. The origin of the avalanche is the result of a decompression in the slopes of the valley after they have been liberated of the glacier ice (paraglacial stress relaxation). Based on geomorphological data and the implementation of a GIS, the reconstruction of ice masses during the main glacier stages have been carried out in order to quantify the stress relaxation that produced the collapse
Efecto en la temperatura de las visitas turísticas en la Cueva del Águila, Ávila. Valoración de la viabilidad de la cueva para el estudio térmico de su dinámica natural
(Universidad de Huelva, 2010) Domínguez Villar, David; Carrasco González, Rosa María; Pedraza Gilsanz, Javier; Fairchild, Ian J.; Baker, Andy
The present study focuses on the importance of visitors in Eagle Cave temperature, a tourist cavern in Ávila, central Spain. Cave air temperature was measured during a year and natural and anthropogenic thermal effects were identified. Eagle Cave has a rather stable temperature around 15.6ºC with an annual cycle which amplitude is <0.4ºC. Recorded seasonality in the cave is related to external temperatures due to thermal conduction through the bedrock, with an expected delay of several years for the external signal to be transferred into the cave. The visitors cause increases in diurnal temperature up to 0.15ºC, although thermal anomalies are normally recovered overnight. During vacation periods, where consecutive days with large number of visitors increases, thermal anomalies are prolonged for some days or weeks, with amplitudes <0.1ºC. Although visitors have a daily impact on the cave temperature, the effect does not cause long term change in Eagle Cave temperature. The reason for this thermal mitigation is related to the high humidity of the environment, which causes the energy supplied by tourists to be partially transferred as latent heat via evaporation and condensation processes. The current condensation processes are insufficient to cause any discernible condensation corrosion that could be damaging recent stalagmites
Efecto de los cambios de usos del suelo sobre la recarga del acuífero Motril-Salobreña
(Universidad de Huelva, 2010) Pretel, Rosa María; Duque, Carlos; Calvache Quesada, María Luisa
Human activity over Motril-Salobreña aquifer (south of Spain) is changing traditional land uses during the last 50 years. In this work we aim to evaluate and quantify the main changes analyzing the aerial photos of different years. The results show a dramatic decrease in the crops of sugarcane and elevated increases of the greenhouses and subtropical trees agriculture extent. Also the surface of the urban areas has been extended noticeably. The direct consequences calculated in this work are a decrease of the recharge of the aquifer by irrigation of crops near to 75 %. The velocity of these changes and the magnitude of them point out the serious risk that involves the Motril-Salobreña aquifer resources

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