Geogaceta -- Nº 34, (2003)

Permanent URI for this collectionhttps://hdl.handle.net/10272/8965

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Un nuevo dinosaurio terópodo («Prodeinodon»sp.) en el Cretácico Inferior de La Cantalera (Teruel)
(Sociedad Geológica de España, 2003) Ruiz Omeñaca, José Ignacio; Canudo, José Ignacio
We describe four theropod teeth from the Upper Hauterivian-Lowermost Barremian of La Cantalera (Teruel, Spain), characterized by the presence of denticles only in their distal edge, being the mesial one rounded. These two features suggest affinities with Velociraptorinae, but also with Compsognathidae and Troodontidae, and so they are assigned to Maniraptora. La Cantalera's teeth resemble the holotypes of Megalosaurus dunkeri Dames, 1884 from the Berriasian of Germany and Prodeinodon mongoliensis Osborn, 1924a from the Hauterivian of Mongolia, and are assigned to "Prodeinodon" sp. Megalosaurus dunkeri has been placed in its own genus, Altispinax, but this name is normally used for three articulated dorsal vertebrae from the Wealden of England. We propose the name "Prodeinodon" dunkeri (Dames, 1884) n. comb, for the German Megalosaurus. "Prodeinodon" is only known by isolated teeth and is classified as Maniraptora incertae sedis
Timing of rodingitization at the Ronda peridotites (Betic Cordilleras, Spain)
(Sociedad Geológica de España, 2003) Esteban, José Julián; Cuevas, Julia; Seward, D.; Tubía, José María
This work reports the timing of the rodingitization process of granitic dykes intrusive into the Ronda Peridotites. Representative fission-track ages on zircon and apatite from rodingitized dykes, in combination with cooling rates suggested for the Alpujarride Complex (Monié et al., 7 994; Sánchez-Rodrfguez, 1 998; Sosson et al., 1998) point to a minimum age of 16.8 ± 1.8 Ma for the rodingitization process. By extrapolating to the timing of formation of the highest stability limit of the serpentine minerals (500°C) we propose that the serpentinization of Ronda peridotites was a continuous process lasting at least for 2.2 Ma, from 19.1 to 16.9 Ma.
The calciclastic members of the Eocene Anotz Formation (Navarre, W Pyrenees): example of resedimentation processes in carbonate ramp slopes
(Sociedad Geológica de España, 2003) Payros, Aitor; Pujalte, Victoriano; Orue Etxebarria, Xabier
The four calciclastic members of the Lower-Middle Eocene Anotz Formation in the western Pyrenees, considered by some previous authors of shallow-marine origin because of their large size, massive appearance and abundant content of shallow-water fossils, are here re-interpreted as deep-marine, resedimented deposits. Eight different calciclastic facies have been recognized, all formed by sediment gravity flows derived from an adjacent shallow-water ramp to the west, showing that high-energy marine currents swept the shallow ramp and shed loose grains as sustained sediment gravity flow off to the ramp slopes. This example shows the need of careful petrosedimentological analyses to correctly address the depositional setting of calciclastic accumulations
Sedimentología e interpretación paleoambiental de la sucesión con niveles de vertebrados fósiles del Eoceno superior de Zambrana (Cuenca de Miranda-Treviño, Álava)
(Sociedad Geológica de España, 2003) Iriarte, Eneko; Badiola, A.; Hernández, José María; Berreteaga, A.
The Zambrana vertebrate fossil locality (Álava, Basque-Cantabrian Region) is located within Upper Eocene continental deposits of the Miranda-Treviño Basin. According to the sedimentological studies of this work, the fossiliferous beds are palustrine-lacustrine coal-bearing marls and limestones. They correspond to a shallow, low-gradient lake margin palaeoenvironment, with a peripheral swamp. The sedimentation was controlled by changes of water level. The fossil rich levels occur on top of swamp related organic matter rich facies, which were rapidly buried because of a rise of the water level. Therefore, the swamps are essential environment to prevent fast subaerial oxidation of the bones, and after buried by lacustrine facies, to form a reducing environment in water-saturated sediments and to promote the fossUization of the bones
Sedimentación neógena en la Cuenca del Río Zeballos y del Río Jeinemeni (47Q de Latitud Sur). Antepaís patagónico, Argentina
(Sociedad Geológica de España, 2003) Dal Molin, C. N.; Colombo Piñol, Ferrán
Extensive outcrops of Tertiary sedimentary rocks appear between the Cordillera de los Andes and the Lago Buenos Aires in Patagonia. Oligocene marine sedimentary materials of the Centinela Formation crop out in some sectors of the areas crossed by the Jeinemeni and Zeballos rivers in the Province of Santa Cruz. They pass transitionally to the Rio Zeballos Group (Miocene) made up of continental sedimentary rocks. This paper describes the sedimentary Tertiary infill of the Rio Zeballos basin, constituted by three well-differentiated Formations: Jeinemeni, Boleadoras and Correntoso. We have studied the sedimentary profiles from the Lago Buenos Aires Meseta and Río Jeinemeni. These data allows to propose a new model of sedimentation consisting of alluvial fans associated with a deltaic complex and lakes affected by with repeated and periodic changes in the water level
Conferencia. Rudistas: estrategias de crecimiento, período vital y respuesta diagenètica
(Sociedad Geológica de España, 2003) García Garmilla, Francisco
Quisiera que la publicación de esta conferencia sea un sentido homenaje a nuestro compañero Patxi Larrea Bilbao, no sólo por parte de quien escribe estas lineas, sino también de todos sus compañeros de la Sección de Geología de la Universidad del País Vasco. Con anterioridad a 1990, Patxi Larrea trabajó en el'I. G.M.E. e inició los estudios que más tarde cristalizarían en la lectura de su Tesis Doctoral, titulada «Caracterización Petrológica y Geoquímica del Sector Oriental del Batolito de Los Pedroches».. Ya como Profesor de Petrología Endógena en nuestro Departamento entre 1990 y 2003, su investigación se extendió hacia otras lineas, como el vulcanismo del Cretácico superior de la Cuenca Vasco-Cantábrica, o la aplicación de las técnicas geoquímicas y petrográficas al estudio de cerámicas prehistóricas. Siempre fue una persona afable y comunicativa, dispuesta a ayudarnos en todo lo que fuera necesario. Nos ha dejado prematuramente tras una larga enfermedad, pero, esté donde esté, siempre permanecerá en nuestro recuerdo como reflejo de amistad y afecto imborrables
Rocas sedimentarias pérmicas de la plataforma continental uruguaya: el prerift de la Cuenca de Punta del Este
(Sociedad Geológica de España, 2003) Daners, G.; Santa Ana, H. de; Veroslavsky, Gerardo
Permian rocks have been identified at the bottom ofGaviotin borehole, located in the Punta del Este basin (Uruguayan continental shelf), on the basis of sedimentologic and palynological analyses, contributing to reveal the prefift nature of the basin, as well as to establish a correlation of these units with those of the Chacoparanense Basin
Respuesta de diversos tratamientos de conservación en la arenisca del Real Monasterio de Santa María de Sijena, Huesca
(Sociedad Geológica de España, 2003) Lapuente Mercadal, M. P.; Auqué Sánz, Luis
The aim of this paper is to test the effectiveness of certain methods of consolidation in sandstones of different grades of damage. Three organic silicon compounds in different concentrations were applied by spraying. Treated and untreated samples were examined by SEM in order to observe the products of polymerization. Laboratory tests were performed and a comparison of consolidated and original stone has shown that some physical properties have been improved, particularly the reduction of capillarity suction and water absorption. A crystallization test points out the efficacy of the treatments
Regeneración dunar en la Reserva de la Biosfera de Urdaibai (Bizkaia, País Vasco)
(Sociedad Geológica de España, 2003) Monge Ganuzas, M.; Iriarte, Eneko; Cearreta, Alejandro
Promoted by local authorities, a sand-dune regeneration project in the Laida beach (Biosphere Reserve of Urdaibai) started in October 2001. During the first year, two different phases of sedimentary development were observed. Semester 7 (autumn and winter) showed a significant sand accumulation (>3500 m3) due to the dominant NW winds that reached an average velocity greater than 4 m/s. On the other hand, semester 2 (spring and summer) exhibited SE-dominant winds with average velocities between 7-2 m/s. Sand deposition was nill during this period. The final result has been the formation of a supratidal area of 6250 m2 with almost 8 m of maximum height (above national ordnance datum) on this sandy estuarine environment
Propuesta metodológica para la caracterización de la mineralogía magnética en estudios paleoambientales. Aplicación al yacimiento de Atapuerca
(Sociedad Geológica de España, 2003) Bógalo, M. F.; Heller, F.; Villalaín, Juan José; Calvo Rathert, M.; Osete, M. L.; Pérez González, Alfredo
A methodology is proposed, which gives information about the contents of ferrimagnetic and antiferromagnetic minerals with different domain structure in soils and sediments. Isothermal remanent magnetisation (IRM) acquired and measured both at room temperature and at low temperature (77K) provides data which define a set of new parameters: AIRMlc provides information about the fraction of superparamagnetic ferrimagnetics in the studied samples; parameters C and g, respectively, inform about absolute and relative contents of goethite, and parameters B and b discern the fraction of goethite, in superparamagnetic state. The proposed methodology is applied to the study of cave sediments from the palaeo-anthropological site of Atapuerca
Procesos sedimentarios de flujos tractivos y de masas deducidos del análisis granulométrico en sedimentos de la Laguna de Gallocanta. Cordillera Ibérica. Ne España
(Sociedad Geológica de España, 2003) Roc, A. C.; Pérez García, Antonio
By the grain-size study of the detrital sediments in Gallocanta lake, two types of detrítica! facies have been defined: gravels facies and sands facies. Depending on the depth of the water different physical processes can be observed. If the lake is dry, the currents that come to Gallocanta lake deposit the materials giving place to small channels developed by stream fload. If the lake has water, until 2 meters of depth, they take place the mass flow processes with high energy, caused by the arriving of stream fload generated by storms inside the lacustrine water. Only in some points of the lake we identify beach processes in relation with moments of highly water level, capable of generating waves for the action of the wind
Primera cita de un dinosaurio hadrosaurio en el Cretácico Superior del Prepirineo oriental (Peguera, provincia de Barcelona)
(Sociedad Geológica de España, 2003) Pereda Suberbiola, Xabier; Ruiz Omeñaca, José Ignacio; Ullastre, J.; Masriera, A.
A right distal femur of a small-sized ornithopod from the Late Cretaceous of the Barcelona province is described. It comes from the Maastrichtian sandstones of Peguera, near Berga, in the Pyrenean region of Bergueda (Barcelona). The femur was originally regarded as belonging to the basal iguanodontian Rhabdodon priscus, but it is here referred to Hadrosauridae on the basis of the anteroposterior expansion of the distal condyles and the possible closure of the anterior intercondylar groove. The Peguera femur is similar to those of Telmatosaurus and "Orthomerus" from Europe, but it is too fragmentary for an accurate determination, so it is provisionally referred to Hadrosauridae indet. This is the first mention of a hadrosaurian dinosaur from the province of Barcelona
Presencia de ámbar en facies de lagoon en eí Albiense superior de El Páramo de la Lora (vertiente norte, Palencia)
(Sociedad Geológica de España, 2003) Martínez de Rituerto Ibisate, S.; López del Valle, R.; García Mondéjar, Joaquín
A new discovery of in situ amber from the Lower Cretaceous series of the northern side of the "Páramo de la Lora" is reported. A detailed analysis of the outcrop section revealed facies attributed to transitional continental-marine enviroments (lagoon). Amber globules were found within siltstones beds on erosion surfaces. After exhaustive examinations gaseous and fungi inclusions appeared. Palaeoenviromental interpretation suggests that the amber was deposited during storms in a restricted lagoon
Período vital y ciclos de crecimiento en Praeradiolites ciryi e Hippurites quintanalomensis (Hippuritacea, Bivalvia, Cretácico Superior de Gredilla de Sedano, Norte de Burgos, España)
(Sociedad Geológica de España, 2003) Regidor Higuera, I.; García Garmilla, Francisco; Zuluaga, María Cruz; Elorza, Javier
Several specimens of Praeradiolites ciryi FLOQUET (1991) and Hippurites quintanalomensis FLOQUET (1991), taken from the Quintanaloma Formation sediments (Upper Campanian-Lower Maastrichtian) at Gredilla de Sedano section (Burgos, Northern Spain) have been studied for determination of their growth velocity, life-span and different types of cyclicity. H. quintanalomensis has a mean growth velocity of 0.30-0.45 cm/year, with a maximum of 0.79 cm/year and having a life-span of 20 years. On the contrary, P. ciryi shows more variable growth velocities, usually between 0.2 and 0.8 cm/year, with a maximum of 1.52 cm/year, varying the life-span from 9 to 13 years. Daily, tidal, monthly and annual cycles have been detected into sclerochronological profiles of these rudist shells. Fortnightly tidal cycles currently show an incomplete number of daily cycles (8-9 for H. quintanalomensis; 10-75 for R ciryi) represented by an alternance of clear/obscure laminae couples. Monthly cycles enclose a pair of tidal «doublets» and annual cycles (megarhythms) may include up to 25 «doublets» limited by densely-condensed obscure growth-lines. Annual cycles are more easily observable when P. ciryi develops «honeycomb» microstructures. This cellular microstructure tends to disappear coinciding with the wintry limit between years
Organización interna de unidades de alta presión en dominios tectónicos profundos (Complejo de Cabo Ortegal, NO España)
(Sociedad Geológica de España, 2003) Puelles, Pablo; Ábalos, Benito; Gil Ibarguchi, José Ignacio
High-pressure volcanic-arc granulites, N-MORB eclogites and shallow crustal volcanosedimentary high-pressure gneiss units occur in the high-pressure metamorphic fold-nappes and ductile thrusts that make up the Cabo Ortegal upper allochthons. Confluence of units from such disparate tectonic settings occurred at an eo-Hercynian convergent plate margin, that in this case, involved oceanic, arc and continental lithosphere. We argue that the sheath-like form of the fold nappes and the mineral and stretching lineations defined by high-pressure mineral assemblages subparallel to fold axes depict the internal organization of high-pressure sheets at deep tectonic realms of an oblique subduction/collision orogenic channel
Nuevos datos geocronologicos Rb - Sr del pluton de Campanario - La Haba (batolito de Los Pedroches, Extremadura)
(Sociedad Geológica de España, 2003) Alonso Olazabal, Ainhoa; Ortega, Luis Ángel; Menéndez, M.; Carracedo Sánchez, Manuel; Aranguren, A.
A Rb-Sr whole-rock array corresponding to a circa age of304 ± 6 Ma has been obtained for the peraluminous granite of Campanario - La Haba pluton. The Sr initial ratio of 0.70619 ± 0.00034 of this pluton is less radiogenic than those typical S granites of metasedimentary crustal origin, indicating that this granite may not have been exclusively derived from crustal sources. The emplacement occurred during late-Hercynian deformation events
Mineralogia del limite Ypresiense/Luteciense de Fortuna (Murcia)
(Sociedad Geológica de España, 2003) Mancheño, Miguel Ángel; Rodríguez Estrella, Tomás; Romero, G.; Hernández, J. M.; Arana, R.; Fernández, M. T.
The Fortuna section has been studied in order to select a suitable section in Spain that could be a good candidate to define the Ypresian/Lutetian boundary stratotype. At present, this section is the most suitable, mainly because it is a complete marine section, well exposed and very rich in microfossils. A variation of mineralogical composition on the clays coincides with the most important change in planktonic foraminifera across the Y/L boundary. At this location, the data allowed us to infer a transgressive event associated with important hot and wet climatic changes that are the origin of an alteration and neoformation processes of clay minerals
Mineralogía de arcillas y diagénesis en la Formación de Quintanaloma (Cretácico Superior, Norte de Burgos, España)
(Sociedad Geológica de España, 2003) Regidor Higuera, I.; Zuluaga, María Cruz; García Garmilla, Francisco; Elorza, Javier
The preliminary results of mineralogical analysis of 28 inner platform carbonate samples taken from the Quintanaloma Formation sediments (Upper Campanian-Lower Maastrichtian) at the Credilla de Sedano section (northern Burgos) are presented. Calcite is the most important mineral and is represented by both micritic matrix and «blocky» crystals derived from cementation and recrystallization of bioclasts. Ankerite is thought to have been formed under early diagenetic conditions. Its iron source was probably related to continental soils and further flocculation favoured by humic adds at low salinities into a gently dipping carbonate ramp. Detrital siliciclastic minerals indicate the influence of a deltaic system which became less active towards the upper half of the section. Clay minerals are clearly inherited in origin and confirm: a very low diagenetic degree. So it is suggested from the presence of kaolinite along the whole studied section and the less-transformed smectite (RO). Smectite is associated to siliciclastic inputs related jto distal but not necessarily deep areas of a possible deltaic apparatus. Kaolinite is persistent along the whole section and was probably formed under the humid and warm climatic conditions that largely dominated the Norcastilian Platform during the late Cretaceous. Finally, detrital illite is widely documented in the most part of the less-diagenetized sections of the Basque-Cantabrian Basin
Mineralogia, texturas y cosmoquirmca de condrulos RP y PO en la condrita Reliegos L5 (Leon, España)
(Sociedad Geológica de España, 2003) Muñoz Espadas, M. J.; Martínez Frías, J.; Lunar Hernández, Rosario
The chondrite Reliegos, fell in the León Province in 7947, is the last recognized meteorite recovered in Spain. It is a L5 chondrite, with olivines Fa22t2S2, and low Ca pyroxenes En7547e7 Fs20U226. Due to the intense recrystallization it has suffered, ehondrules are rare, and their rims are poorly delineated. However, ehondrules of different types have been identified. Their compositional and textural characteristics are described, together with the elemental distribution inside the ehondrules, by punctual electron microprobe analysis and PIXE profiles
Metamorfismo de AP/BT en metapelitas de la unidad de Ragua (complejo Nevado-Filábride, Cordillera Bética). Resultados termo-barométricos del estudio de equilibrios locales
(Sociedad Geológica de España, 2003) Booth Rea, G.; Azañón, José Miguel; Martínez Martínez, Javier
We have analysed the thermobarometric equilibrium conditions reached during local equilibria among phengite + chlorite + quartz + water ± chloritoid ± garnet assemblages found in metapelites of the Ragua unit, the structurally-lowest tectonic unit outcropping in the Betics hinterland (southern Spain). Porphyroblast- deformation relationships show that lenticular domains preserved within the main foliation in the metapelites grew during a HP/LT prograde metamorphic event with thermal conditions of 320-450 °C and 12-14 kbar pressure. Hence, the Ragua unit subducted in a continental accretionary-wedge context, undergoing a tectonic evolution parallel to the one followed by the two other overlying Nevado-Filabride units

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