Geogaceta -- Nº 47, (2009)

Permanent URI for this collectionhttps://hdl.handle.net/10272/7953

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Unidades Preordovícicas y Megaestructuras Cadomienses en La Serena y La Siberia Extremeña (Macizo Ibérico meridional)
(2009) Apalategui, Octavio; Eguiluz, Luis; Martínez Torres, Luis M.; Palacios Medrano, Teodoro
New mapping of the pre-Ordovician basement (Schist and Greywacke Complex or Lower Alcudian) from the La Serena and La Siberia Extremeña regions of the southern Central Iberian zone has allowed the distinction of up to four independent stratigraphic units. The studied sequence is exposed in two megastructures: the Almorchón-Valdecaballeros Antiform and the Cerro de los Moros Synform, separated by the Patin Fault, which seems to correspond to an ancient paleogeographic boundary. The continuity of these structures under the Paleozoic synclines and the sub-orthogonal directions with respect to those of the Variscan cover is regarded as an evidence for deformational events related to the Cadomian (pan- African) cycle, likely in connection to those recorded in the adjacent Ossa-Morena Zone
Unidades evaporíticas eocenas de la Zona Surpirenaica Oriental (Área de La Garrotxa)
(2009) Carrillo Álvarez, Emili
Three Eocene evaporite units are distinguished in La Garrotxa area (Southeastern Pyrenean Zone, NE Spain) on the basis of geological mapping with integrated sedimentological, structural and borehole data. These units were deposited in a foreland basin during Lutetian time: (1) the oldest and thickest one, the Borró Evaporitic Unit, was deposited in both platform setting and slope-basin environments, previously to the turbidite deposition of the Vallfogona Formation, (2) the Beuda Gypsum Unit was deposited overlying these turbidites, with no differentiated paleogeographical environments, and (3) the youngest and thinnest one, the Besalú Gypsum Unit, was deposited in a siliciclastic platform, just before the change from marine to continental conditions in the basin. As a whole, this evaporitic evolution reflects decreasing intensity in the successive salinity crises in the foreland basin in parallel with its progressive filling and loss of marine influence
Turbiditas carbonatadas en la Playa de Muriola (Barrika, Arco Vasco): edad, deformación, contenidos de CaCO3 y presencia de barita diagenética
(2009) Alonso de Linaje, Virginia; Fernández Lerín, Bárbara; Apodaca, Jon; Biain, Ander; Jaca, Esther; Hernández Martín, Sergio; Elorza, Javier
The Playa de Muriola sea-cliff exposes three different sections of carbonate turbidite layers from the Early Turonian of the deep Basque Arc domain. High-resolution analysis (% CaCO3) of the turbidites (calcarenites and marls) points out: a) a major CaCO3 content in calcarenites than in marls; and b) a decrease tendency in carbonate content from the bottom towards the top of the calcarenite bed. We confirm an intense softsediment deformation (simple-double wedges, deformation bands, shear vein systems, etc.). Also, the presence of a small anoxic event, red-marls corresponding to the Cretaceous oceanic red beds (CORB's) and an unusual barite (BaSO4) nodules are discussed
Revisión histórica y sistemática del primer hallazgo de tetanuros basales (Theropoda) del Cretácico Inferior de Morella (Castellón)
(2009) Pérez García, Adán; Ortega, Francisco; Gasulla, José Miguel
Historic and systematic aspects of a partial left femur determined as belonging to an undetermined tetanuran theropod are discussed. Probably, the fossil was collected in the ending of the XIX century in the Lower Cretaceous sediments of the Morella Formation, near to the town of Morella (Castellón). The original specimen was destroyed by a fire in 1932, but some casts and documents are still housed in the Museo Nacional de Ciencias Naturales in Madrid
Relaciones entre tectónica y sedimentación asociadas a las Rides Prérifaines en la Cuenca de Volubilis (frente del Rif, Marruecos)
(2009) Roldán García, Francisco Javier; Galindo Zaldívar, Jesús; Chalouan, Ahmed; Anahnah, Farida; Ahmamou, M’Fedal; Ruano, Patricia; Ruiz Constán, Ana; Sanz de Galdeano, Carlos; Ben Makhlouf, Mohamed; Marín Lechado, Carlos; López Garrido, Ángel Carlos; Pedrera Parias, Antonio
The Volubilis Neogene basin (Morocco) was part of the South Rif Corridor that connected the Atlantic Ocean with the Mediterranean. This basin recorded the tectonic - sedimentary interactions of a foreland basin subjected to the progressive advance of the Rif mountain range front. Since the Miocene, the displacement of the Prerif to the WSW, caused the detachment of the Mesozoic and Cenozoic cover from the Variscan basement and the compartimentation of Saïss Basin. Simultaneously, the upper Neogene sedimentation continued, developing several types of syntectonic sedimentary structures and Volubilis basin finally becomes a piggy-back basin
Registro del evento 8.2 ka en la plataforma continental de Alicante (SE, España)
(2009) Tent Manclús, José Enrique; Estévez, Antonio; Soria, Jesús M.; Benabdeloued, Nassim Y.B.; Corbí, Hugo; Rey Salgado, Jorge; Pina, José Antonio; Yébenes, Alfonso
High resolution seismic profiles of the Alicante continental shelf have been studied identifying a seismic prism which top at about -20 m below today sea-level. The prism is covered by recent sediments and can be interpreted as formed during a short interval of stand-by in the general transgression after the last glacial maximum. The -20 m level have been compared with the holocene Mediterranean sea-level-curve to propose an age of about 8 ka BP coinciding with the «8.2 ka cooling event» that was an abrupt, widespread climate instability. The prism top is deeper in the northern seismic profiles thus indicating a more subsidence that the southern coastal shelf where an erosion surface with rocky shoals configure the sea bottom
Prospecciones paleoicnológicas en el sinclinal de Iouaridène (Alto Atlas, Marruecos). 2: Parte oriental
(2009) Boutakiout, Mohamed; Ladel, Latifa; Díaz Martínez, Ignacio; Pérez Lorente, Félix
In 2007, the dinosaur footprints research group of the Universities of Rabat and La Rioja began the mapping of the Iouaridène ichnological sites. The initial problems were the footprints number - several thousands for some scientits- the ichnotaxonomy, and their geographical and geological distribution. Our first results (west Iouaridène area) were published in 2008. In addition to two ichnotaxons defined here, we have studied: gigantic theropod and ornithopod footprints; semipantigrade theropod ichnites and the largest world theropod trackway are new contributions to Iouaridène dinosaur footprints knowledge. In this work, are demostrated the following questions: i) the maximun number of footprints in the Iouaridène sincline is less than 2000; ii) in the east area there is minor density of sites and the number of footprints that in the west part; iii) the greatest number of semiplantigrade theropod ichnites; iv) the fosiliferous levels reduction from 20 to one. Probably, the four properties geographically related - stratigraphic, number, density (sites and footprints) and the diversity of semiplantigrade ichnites - are other singenetic relations
Primer hallazgo de graptolitos oretanienses (Ordovícico Medio) en el Cabo Vidrias (Asturias, extremo noroccidental de la Zona Cantábrica)
(2009) Bernárdez Rodríguez, Enrique; Gutiérrez Marco, Juan Carlos
The discovery of Didymograptus (Didymograptus) artus Elles and Wood in the Ordovician section of the Vidrias Cape (Atlantic coast of Spain), constitutes the first record of early Oretanian (= mid Darriwilian) rocks in the Cantabrian Zone of the Iberian Massif. The fossil locality lies in a shaly intercalation towards the middle part of an easternmost equivalent of the «Sabugo Quartzite» of the Navia Domain (West Asturian-Leonese Zone), so far unknown in the reference section for the Ordovician of the Cantabrian Zone of the nearby Peñas Cape. Correlations of the studied strata by previous authors are also reviewed, and the existence of a fault is suggested to occur between the «Peñas» and «Vidrias» members of the Luarca Formation on the famous section of the Peñas Cape
Primera descripción de restos esqueléticos de dinosaurio ornitópodo en la Formación Villar del Arzobispo (tránsito Jurásico-Cretácico): yacimiento de Cerrito del Olmo (Alpuente, Valencia)
(2009) Pereda Suberbiola, Xabier; Ruiz Omeñaca, José Ignacio; Company, Julio
The Villar del Arzobispo Formation (Tithonian-Berriasian) in Teruel and Valencia provinces (SE Iberian Range) has yielded abundant skeletal remains of dinosaurs, mainly of sauropods and stegosaurs. Three vertebrae collected in the locality of Cerrito del Olmo I (Alpuente, Valencia province), two of them previously referred to the stegosaurid Dacentrurus armatus, belong in fact to an ornithopod. The material consists of one cervical and two caudal centra that preserve the base of the neural arch fused to the centrum. These remains are here assigned to Ornithopoda indet. on the basis of the combination of several characters more frequent in ornithopods than in stegosaurs. This is the first description of ornithopod skeletal remains from the Villar del Arzobispo Formation
Presencia de cloritoide en la aureola térmica de los plutones de Cauterets occidental-Panticosa (Zona Axial del Pirineo, Huesca)
(2009) Rodríguez, Lidia; Cuevas, Julia
The Cauterets-Panticosa granite complex, including Panticosa, West-Cauterets and East-Cauterets plutons, crops out in the Axial Zone of the Pyrenees, and generated a continuous metamorphic zone. In the Tena Valley, Panticosa and West-Cauterets plutons are intrusive in a Devonian metasedimentary series that show a low regional metamorphism. In the thermal aureole, limestones are transformed into marbles and pelitic rocks into hornfelses. The most common minerals in metapelitic rocks are biotite + andalusite ± muscovite ± cordierite ± almandine. In this region the thermal aureole cartography is based on the presence of andalusite. In this work, we describe for first time the presence of chloritoid. The chloritoid is overprinting the rock fabric of the fine-grain schists. The microprobe analysis of chloritoid resulted in high contents of FeO and low contents of MgO and MnO. Finally, the geological implications of the chloritoid determination up to 1.5 km from the cartographic aureole were discussed
Pistas fósiles asociadas a la discontinuidad fini-Messiniense en el margen norte de la Cuenca del Bajo Segura (SE España)
(2009) Caracuel, Jesús Esteban; Corbí, Hugo; Estévez, Antonio; Giannetti, Alice; Monaco, Paolo; Pina, José Antonio; Soria, Jesús M.; Tent Manclús, José Enrique; Yébenes, Alfonso
A detailed analysis of the Upper Messinian-Lower Pliocene at the northern border of the Bajo Segura Basin (BSB) has been carried out. Trace fossils of firm- and rockground were collected, aiding in the recognition of three ichnofacies: Glossifungites (types A and B), Entobia and Gnathichnus. The ichnological data provide evidence that the Pliocene flooding of the BSB, after the Messinian Salinity Crisis, was developed in two pulses. In the first one, the ingression penetrated only along the paleovalleys and produced a coastal trasgressive lag (P0). In the second one, the ingression overflowed the margins of the paleovalleys and extended throughout the entire northern margin, also producing a coastal transgressive lag in the base of the P2 system. The record of the Entobia and Gnathichnus ichnofacies in the clasts of both lags evidences a relatively fast deepening-upward trend in both the transgressions
Paleoclima y diagénesis en las calizas rojas de Ereño (Aptiense superior-Albiense inferior, Bizkaia)
(2009) Damas Mollá, Laura; Aranburu Artano, Arantza; García Garmilla, Francisco
Carbon and Oxygen isotopic values measured on rudist and Chondrodonta sp. shells from the red urgonian limestones of Ereño (Upper Aptian-Lower Albian, Bizkaia) have been demonstrated to be a very useful tool for reconstruction of both palaeoenvironmental features and diagenetic conditions that affected the famous ornamental stone. The δ18O‰ (PDB) values obtained from rudist recrystallized hipostraca suggest an influence of increasing diagenetic temperatures rather than the action of meteoric waters during early diagenetic stages. On the other hand, the δ18O‰ (PDB) values from diagenetically less-affected shells (Chondrodonta sp.) and parts of the shells (rudist miostraca) reveal palaeotemperatures of 19-27ºC very close to those of coetaneous marine waters and compatible with the seasonal variations described for a 30ºN palaeolatitude in the Tethys domain. Palaeoesalinities in the marine waters of the Ereño platform could oscillate between 32-36‰, slightly above the normal values recorded at present
Ostreidos de la Unidad de Sopuerta (límite Aptiense inferior/ superior; Cuenca Vasco Cantábrica): estudio geoquímico y diagenético
(2009) Ibisate, Ruth; Elorza, Javier
The realization of geochemical and diagenetical studies on fossil oyster’s shells from the «Calizas Nodulosas con Ostreidos y Limolitas de Sopuerta unit» has allowed demonstrating the variations in the luminescence of different microstructures, mainly in the Regular Foliated one (RF), as a result of different burial depths. The structural properties of the distinguished microstructures made possible, to a greater or lesser extent, the circulation of diagenetic fluids which provided the shell with diagenetic elements like Fe, Mn or Mg. As a result of this cationic exchange, the shell enriched the fluids with Na or Sr, considered primitive elements in oyster’s shells. The importance of the rocky matrix in the geochemical alterations has been demonstrated, comparing the results of this study with the results obtained by Higuera-Ruiz and Elorza (2006)
New occurrences of Meyeria magna M‘Coy, 1849 (Decapoda, Mecochiridae) in the early Aptian and early Albian of the Basque Cantabrian Basin (North Spain)
(2009) López Horgue, Mikel A.
En este trabajo se citan dos nuevos registros de la langosta Meyeria magna M‘Coy, 1849 en series terrígenas de mar somero del Aptiense inferior y Albiense inferior aflorantes en la costa de Cantabria. Se acompaña una sucinta descripción y discusión taxonómica preliminares. Asimismo, el límite superior del rango estratigráfico de la especie queda bien establecido
Los deslizamientos submarinos de Águilas (Margen de Palomares, Mediterráneo Occidental)
(2009) Pérez Hernández, Silvia; Comas, Menchu; Escutia, Carlota; Martínez García, Pedro
Morphological and structural features observed in both swath bathymetry and parametric sub-bottom profiles, acquired during the MARSIBAL I-06 cruise, reveal an area highly affected by sedimentary instability processes at the Águilas Sector in the northern Palomares Margin. Failure scars and deposits, governed by a major lineation of scars -the Águilas Escarpment-, occupy and shape the lower continental slope of this margin sector and extend till the continental rise. Submarine and buried slides complexes cover an area of about 180 km2, and develop from 1600 to 2400 m water depths. High angle faults, which deform the seafloor cause the Águilas Escarpment and diverse small-scale submarine slides. Recent or sub-recent active tectonics, and the coeval uplifting of the Palomares Margin, is proposed to be the main trigger mechanism for the slides. The failure scars favour the evolution of a juvenile submarine canyon (the Águilas Canyon) due to retrogressive sliding
Los depósitos de Mn-Al-Fe de la cueva de Lazalday (Zarate, Alava): composición química y mineralogía
(2009) Yusta, Iñaki; Castellano, Amaia; Aranburu Artano, Arantza; Velasco, Francisco
Lazalday Cave is a 4 km long karstic cave where Mn deposits occur as black thin coatings covering walls and cementing conglomerates, inside calcite speleothems, and also in the floor of many passages alternating with Al-Si white gels. Fe-rich deposits are found forming black stalactites and microgours. Asbolane, allophane, hydrated halloysite, goethite, ferrihydrite and X-ray amorphous phases compose respectively the Mn-Al and Fe deposits. High metal contents of 21.5% MnO, 5.1% Zn, 2.5% Ni, 0.9% Co, and 0.2% Cu were recorded in Mn-rich levels. Allophane and Fe deposits also trap heavy metals, but in lower proportions. The presence of abundant gypsum, hydrated halloysite and jarosite point out an acidic alteration from pyrite-bearing rocks. Potential metal source rocks are discussed
Las marismas costeras como archivos geológicos de las variaciones recientes en el nivel marino
(2009) García Artola, Ane; Cearreta, Alejandro; Leorri, Eduardo; Irabien, María Jesús; Blake, William
In order to evaluate the accuracy and regional significance of salt-marsh reconstructions of former sea level based on foraminiferal transfer functions, we have calibrated the foraminiferal assemblages of a saltmarsh core from the Urdaibai estuary using the regional transfer function constructed previously for the southern Bay of Biscay. The foraminifera-based reconstructions were placed into a temporal framework using Pb-210, heavy metal concentrations, and Cs-137-derived sediment accumulation rates. The resulting relative sea-level curve has been compared with the nearest tide-gauge data (Santander) and with other geological records from regional salt-marshes. Relative sea-level trends from core sediments support in all cases the idea of accelerating sea levels over the last century when compared to previous centuries, providing a regional relative sea-level rise of 2.0 mm yr-1 for the 20th century
Las espesartitas, camptonitas y bostonitas del complejo intrusivo de Aiguablava (Cadenas Costeras Catalanas): cartografía y composición
(2009) Enrique Gisbert, Pere
The lower Permian Hercynian Aiguablava leucogranite (288 Ma) is intruded by a dense vertical dyke swarm and a few subhorizontal dykes that fill several joint systems developed during the crystallization and cooling of the plutonic intrusions. The hypabyssal rocks have been divided into three groups: 1) felsites and granophyres (out of the studied area in this work), 2) calc-alkaline lamprophyres (spessartites), probably upper Permian (253 Ma whole-rock K-Ar age) and 3) upper Cretaceous (76 Ma) alkaline lamprophyres (camptonites). This work provides new cartographic and geochemical data that allow to show the morphology, distribution and dimensions of the intrusions and the presence of a fourth type of differentiated alkaline lamprophyres (bostonites) not previously described in the Catalan Coastal Ranges
La plataforma urgoniana aptiense del sur de Bilbao (valle de Bolintxu): organización estratigráfica y evolución
(2009) García Mondéjar, Joaquín; Fernández Mendiola, Pedro Ángel; Millán, María Isabel; Mendicoa, Jone
An Aptian rudist limestone unit, up to 200m thick and extending more than 3km, lies 2km to the south of Bilbao. The stratigraphy and mapping of the limestones in the Bolintxu valley reveal diachronous lower and upper boundaries grading laterally to sandy and marly facies respectively. A carbonate ramp model with southeastwards backstepping in three pulses indicates a deepening upward trend. Depositional dip of the ramp down to the west suggests westward tilting and development of enhanced subsident areas to the west. The orbitolinids indicate an Early Aptian (Late Bedoulian) age for the nuclear part of the ramp
Juan Vilanova y Piera (1821-1893) y la primera tortuga hallada en el Mesozoico español
(2009) Pérez García, Adán; Ortega, Francisco
MNCN 59511 is a natural inner cast of the caparace of a Pancryptodiran turtle from the Lower Cretaceous of Morella (Castellón), whose discovery was attributed to José Royo y Gómez. However, information available at the Museo Nacional de Ciencias Naturales (Madrid) shows that the fossil was actually collected in the second half of the nineteenth century by Juan Vilanova y Piera, constituting the first known discovery of a turtle in the Spanish Mesozoic

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