Geogaceta -- Nº 38, (2005)

Permanent URI for this collectionhttps://hdl.handle.net/10272/8620

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Variaciones de rango orbital en la dinámica de la Nutriclina/Termoclina en el Pacifíco Ecuatorial durante los últimos 500 Ka indicado por cocolitofóridos (Site 1240, Leg 202)
(Sociedad Geológica de España, 2005) López Otálvaro, G. E.; Flores, José Abel; Sierro, Francisco Javier
The ODP Site 1240 is located in the equatorial cold tongue in the Eastern Equatorial Pacific. The analysis of the calcareous nannofossil assemblages allow us to monitor fluctuations in the Nutricline/Thermocline over the last 500 Ka, using the relationship between the upper photic zone taxa (small placoliths) and the lower photic zone taxa (Florisphaera profunda), by means of the N ratio function. The variations in this N ratio pointed out two intervals with dominant higher relative abundances of small placoliths over Florisphaera profunda, and other interval with an abrupt increasing in the relative abundance of Florisphaera profunda over the small placoliths, controlled esentially by a precessional force, and during the last 177 Ka by a markedly excentricity component
Variaciones microfaunísticas en el Cenomaniense superior a Turoniense superior de la Plataforma Norcastellana (área Puentedey-Santelices, Norte Burgos): respuesta morfológica de los inocerámidos
(Sociedad Geológica de España, 2005) Pascual, Ana; Higuera Ruiz, R.; Elorza, Javier
Analyses carried out on benthonic foraminiferal assemblages of the Puentedey-Hornillalatorre formations (Norcastilian Platform) are part of a multidisciplinary research with the main subject of understanding the palaeoceanographic events that took place at the end of the Cretaceous within the Basque-Cantabrian Basin. The study sections have been dated from the late Cenomanian to the late Turonian. A total of 98 benthonic species have been identified, which clearly correspond to shallow marine water microfauna. In this context, some of the aspects about the palaeoenvironmental variations detected in Puentedey-Santelices area are crucially provided by changes of the foraminiferal assemblages (Units 1 to 3), specific diversity changes of the microfauna, the rate between different type of tests of benthonic, percentage of keeled, incipiently keeled and globular planktonic foraminifera and oceanicity index. Thus, the dominant foraminiferal assemblages, the great percentage of agglutinated tests, and the lower values of the oceanicity index suggest a cool, acid, and bad-oxygenated internal platform (<100 m) waters palaeoenvironment (Units 1-2). The inoceramid bivalves I. (Mytiloides), with thinner shells and grey colour are well-developed. The Unit 3, marked by oxygenated internal platform waters palaeoenvironment, where I. (Mytiloides) are replaced by I (I) lamarcki, with thicker shells and caramel colour
Variación de las tasas de sedimentación en el Complejo Detrítico Superior del Delta del Llobregat (Barcelona): su relación con causas eustáticas, climáticas y antrópicas
(Sociedad Geológica de España, 2005) Gàmez, Desire; Simó, J. A.; Vazquez Suñé, Enric; Salvany, José María; Carrera, J.
Sediment accumulation rates have been calculated for the Llobregat Delta and compared to eustasy, climate and land use. Radiometric ages show slow (less than 1 mm/yr) sediment accumulations between 12180±60 BP (14565±715 cal BP) and ~4100 BP (4500 cal BP) and faster rates (12 to 25 mm/yr) younger than ~4100 BP (4500 cal BP). Within this trend of increasing sediment accumulation rates are two peaks of high sediment accumulation; one occurring during the Visigoth period (VI-VIII century) to Upper Medieval Age (X-XIV century) and the second during the economic recuperation (XVIII century). The initial slow sediment accumulation rate is attributed to high rates of accommodation produced by the rapid Holocene transgression and little sediment supply. Following a slower rate of creation of accommodation space, sediment started to accumulate at the mouth of the river and prograde on the shallow shelf. The pulses in sediment accumulation coincide with and are interpreted to increasing pressure anthropomorphic activity together with peaks of aridity
Unidades litoestratigráficas del Terciario del sector de Sepúlveda-Ayllón. Borde suroriental de la Cuenca del Duero
(Sociedad Geológica de España, 2005) López Olmedo, F.; Montes Santiago, M. J.; Nozal, F.; Luengo, J.
Six new Tertiary lithostratigraphic units, each one corresponding to a separate stratigraphic sequence, have been recognized in the southeast border of the Duero Basin (north of the Somosierra - Ayllón Sierra). The age of these units is Paleogene-Late Miocene (Turolian) to Pliocene. The lower units are synorogenic, consequence of the tectonic uplift on the Central System while the upper units are postorogenic. These units are correlated with other ones of equal regional scale and well known age in the Duero Basin
Revisión de la estratigrafía del Grupo Tremp («Garumniense», Cuenca de Tremp-Graus, Pirineos meridionales)
(Sociedad Geológica de España, 2005) Pujalte, Victoriano; Schmitz, Birger
The term Tremp Group reflects more appropriately than the former Tremp Formation the stratigraphic complexity of the so-called «Garumnian» of the south Pyrenean Tremp-Graus basin. However, the current definitions of some of the formal units making up the Tremp Group are somewhat inconsistent. New field observations and, mainly, the discovery of the carbon isotopic excursion of the Initial Eocene Thermal Maximum, permit to correlate key sections of the Tremp Group with far more reliability than was hitherto possible. On the light of that correlation we revise the original definitions of the Talarn, Esplugafreda and Claret Formations, and of some of its members, and propose modifications to clarify their boundaries and ages
Respuesta del registro sedimentario a la ciclicidad solar en el estrecho de Gerlache (península Antártica)
(Sociedad Geológica de España, 2005) Bárcena, María Ángeles; Sesma, J.; Isla, E.; Palanques, Albert
The Gerlache Strait (Antarctic Peninsula) is a semi-enclosed basin that acts as a giant sedimentary trap collecting large amounts of material. Previous biogenic and glacial deposits are the main suppliers of sediments. The basin is also an area of high sea-surface productivity, mostly restricted to the summer months of December and January. In this study we present micropaleontological and geochemical data obtained from a set of four sediment cores obtained by the Spanish research vessel Hespérides during the Fruela-96 expedition. The cores were collected using a multiple corer allowing recovery of up to eight replicates, with core lengths ranging between 32 and 34 cm. The stratigraphic framework of the cores, based in 210Pb activity, shows that there has been a continuous sedimentation in the sites during the last 220 years BP. The diatom assemblage varies between absolute values of 0.9 to 240 x 108 valves/g of dry sediment. Chaetoceros RS are the main contributor showing values from 66 to 90 %. The Thalassiosira antarctica/ scotia group and Sea-ice taxa, mainly Fragilariopsis curta, are secondary contributors. The total abundance of diatoms and the content of biogenic silica are interpreted as paleoproductivity proxies. In this sense, a progressive reduction in paleoproductivity is observed towards the core top, with a sharp minimum around 100 yr B.P. Moreover an increase of Sea-ice Taxa is observed for the last 100 yr. These changes could be related to the onset of a neoglacial event during this period. In order to evaluate the cyclicity record, Spectral analyses (Multi-Tapered Method) were performed on different parameters (TOC, Opal, total diatom abundance, Sea-ice Taxa and T. antarctica). The time series study shows two main types of cyclicities, 80-90 and 20-30 years in two cores, G4 and G5, both recovered from central Gerlache Strait. This cyclicity seems to be in agreement with the Hale (22 years) and the Gleissberg (83 years) Solar Cycles. Both cycles are related to strong solar eruptive activity, which modulate the amplitude of the 11-year sunspot cycle (Schawe Cycle); this cycle was also recognised in our record
Respuesta Estratigráfica a la Transgresión Tortoniense en el Margen Pasivo de la Cuenca del Guadalquivir: Datos Preliminares
(Sociedad Geológica de España, 2005) Abad de los Santos, Manuel; Pendón Martín, José Gabriel; Ruiz Muñoz, Francisco; Rodríguez Vidal, Joaquín; López González, Nieves; Mantero, Isabel
The passive margin of the Guadalquivir foreland basin records different stages of evolution during the tortonian transgression, mainly determinate by sedimentary supply/ accommodation space ratio (A/S ratio, Cattaneo and Steel, 2003). In a first phase, a high supply from the continental and deltaic systems filled quickly the low accommodation space and produced an agradational/progradational stacking pattern of sequences. The second episode is characterized by a change in these conditions, so the passive margin register a high increase of depth and carbonate facies predominates. Finally, the transgressive maximum is registered by means of the formation of a condensed level constituted by glauconitic sands and silts. This transgressive pulse supposed the advance of the shoreline several kilometres towards the foreland
Reconstrucción de las temperaturas superficiales marinas delmargen ibérico sudoriental durante el último periodo glacial mediante el empleo de cocolitofóridos
(Sociedad Geológica de España, 2005) Colmenero Hidalgo, Elena; Flores, José Abel; Sierro, Francisco Javier; Grimalt, J. O.
Detailed quantitative analyses of coccolithophore assemblages have been carried out in three sediment cores recovered from different locations in the Atlantic and Mediterranean sectors of the Iberian Peninsula. Biostratigraphical and oxygen isotope analyses show that these cores provide a high-resolution record of most of the last glacial period. Joint interpretation of the results reveals that higher sea surface temperatures (SST) were recorded in the Atlantic side during that interval. Dansgaard-Oeschger Interstadials are the warmer periods, while during Heinrich Events and Dansgaard-Oeschger Stadials SSTs suffered a substantial decrease, probably due to the appearance of turbid, fresher and colder surface water masses. These quantitative differences in the response of coccolithophore assemblages between the Atlantic and the Mediterranean cores indicate that the Mediterranean Sea shows a more intense response to climatic and oceanographic changes than the Atlantic area
Quantification of Biodegradation: Applied Example on Oil Seeps in Armàncies Fm, Southeastern Pyrenees
(Sociedad Geológica de España, 2005) Permanyer, Albert; Caja, Miguel Ángel
La presencia de petróleo expulsado directamente de la roca madre de la Formación Armàncies, constituye un caso único para el estudio de los procesos de biodegradación aeróbica en petróleo. El estado de degradación bacteriana es moderado y está principalmente limitado a la alteración de n-alcanos, isoprenoides y algunos aromáticos. La cuantificación ha sido realizada mediante el contenido en sulfuro y con los marcadores moleculares de la fracción aromática. Los resultados obtenidos indican que entre un 50 y un 60% del petróleo se ha consumido debido al proceso de biodegradación
Procedencia y edad de las diamictitas del Paleozoico inferior de la cuenca de Perú-Bolivia (Gondwana occidental)
(Sociedad Geológica de España, 2005) Díaz Martínez, Enrique
An extensive diamictite-bearing unit is present within the lower Palaeozoic siliciclastic sequence of the Central Andes. A review of its lithostratigraphy, sedimentology and biostratigraphy allows to differentiate two subunits according to their provenance and age. The correlative San Gabán Formation (Perú), Cancañiri Formation (Bolivia) and Zapla Formation (NW Argentina), of Hirnantian(?)-Llandovery age, presents evidence for resedimentation from a glaciated tectonically-active source area located to the west and south. It includes granitoid boulders, and large olistoliths of late Ordovician units. In central Bolivia, the lowermost Kirusillas Formation (early Wenlock) presents evidence for resedimentation of shallow shelf deposits from a nearby source located to the east and north. It includes olistoliths of the Sacta Limestone Member (earliest Wenlock). Only careful sedimentology and biostratigraphy may discern between the two units when both are present in the same section
Primera evidencia de dinosaurios terópodos en la Formación Mirambel (Barremiense inferior, Cretácico Inferior) en Castellote, Teruel
(Sociedad Geológica de España, 2005) Infante, P.; Canudo, José Ignacio; Ruiz Omeñaca, José Ignacio
We describe here two new dinosaur theropod teeth from the Mirambel Formation (Lower Barremian, Lower Cretaceous) found in Ladruñán (Castellote, Teruel, NE Spain). One of them is included in Baryonychinae, a subfamily well known in other sites of the Iberian Range. The other one belongs to a noncarcharodontosaurid Allosauroidea. This last group of mid and big sized theropods is described for the first time in the Iberian Barremian, and it represents a new evidence of the similarity between the dinosaur faunas from the English Wealden (Isle of Wight) and the «Weald» (Lower Cretaceous) of the Iberian Range
Presencia en Riodeva (Teruel) de la mayor vértebra caudal (Dinosauria, Sauropoda) de Europa
(Sociedad Geológica de España, 2005) Royo Torres, Rafael; Cobos, Alberto
A big caudal vertebra from the Villar del Arzobispo Formation (Tithonian-Berriasian), found in Riodeva (Teruel, Spain), is described in this work. Its main characters are a transverse process deep, extending from the centrum to the neural arch, centra procoelus without condyle, centre with absence of spongy bone texture and lack of pleurocoels. The principal character is the cranio-caudal compression. This vertebra is similar to an isolated vertebra reported in the Cognac region (France) and to the vertebrae of both Cetiosauriscus greppini and Cetiosauriscus stewarti. The four aforementioned taxa would constitute a new clade included in Omeisauridae + (Jobaria + Neosauropoda)
«Pleurocoelus» valdensis Lydekker, 1889 (Saurischia, Sauropoda) en el Cretácico Inferior (Barremiense) de la Península Ibérica
(Sociedad Geológica de España, 2005) Ruiz Omeñaca, José Ignacio; Canudo, José Ignacio
One fragmentary sauropod isolated tooth from the Upper Barremian-Lower Aptian (Artoles Formation) of Vallipón (Castellote, Teruel province, Spain) is described. It has a «parallel-sided» crown and a «compressed cone-chisellike » general form. This tooth resembles the teeth from the Lower Barremian of Boca do Chapin (Estremadura province, Portugal) and Galve (Teruel province) described as Pleurocoelus valdensis/Astrodon valdensis and cf. Astrodon sp., respectively. The Portuguese and Spanish teeth are compared with the teeth of Pleurocoelusvaldensis from England, and Astrodon johnstoni and Pleurocoelus nanus from Maryland (USA), and they show similarities with the English species. Due to P. valdensis and P. nanus could not be congeneric, «Pleurocoelus» valdensis is put with quotation marks. «P.» valdensis is based on several isolated teeth from the Berriasian-Valanginian of Sussex and the Barremian of the Isle of Wight, but no holotype was designated, and all those teeth could represent two or more different sauropods species. The specific name is reserved to compressed cone-chisel-like teeth with enamel ornamented with irregular longitudinal ridges, probably pertaining to brachiosaurid sauropods
Parámetros geomorfológicos y regresión múltiple en el comportamiento hidrológico de caudales en las cuencas altas de los ríos Tajo y Guadiana
(Sociedad Geológica de España, 2005) Potenciano de las Heras, A.; Garzón Heydt, Guillermina
A multiple regression model allows us to interpret differences in flood discharge between Tajo and Guadiana watersheds. Statistical relationships between discharge and rainfall and morphometrical parameters of each subbasin shows up the significance of relief, stream length and either rainfalls or permeability according also to the considered return period
Nuevos yacimientos de icnitas de dinosaurio en Formiche Alto (Teruel)
(Sociedad Geológica de España, 2005) Cobos, Alberto; Mampel, Luis; Royo Torres, Rafael; Espílez, Eduardo; Alcalá, Luis
Three new dinosaur tracksites found in Formiche Alto (Teruel) are described in this paper: El Molino, Camino de Cabra y Barranco de los Arcos. These sites are near Jurassic-Cretaceous boundary in age (Villar del Arzobispo Formation, ranging from Tithonian to Berriasian). The outcrops show higher number of manus prints than pes. The footprints are attributed both to small and large sauropod dinosaurs but there are some tridactyl tracks too. The presence of sauropod footprints from the Villar del Arzobispo Formation is also common in other sites recorded in the province of Teruel
Nuevas evidencias de la presencia de hadrosaurios lambeosaurinos (Dinosauria) en el Maastrichtiense superior de la Península Ibérica (Arén, Huesca)
(Sociedad Geológica de España, 2005) Cruzado Caballero, Penélope; Canudo, José Ignacio; Ruiz Omeñaca, José Ignacio
We describe here in a complete right ilium from Arén (Huesca, Spain). It comes from the Blasi 3 locality, situated in the bottom of the Conques Formation (Tremp Group), in the Tremp Basin (South Central Pyrenees). Blasi 3 is located in a level of grey massive sandy limestone, of Late Maastrichtian in age. The ilium has been regarded as an indeterminate lambeosaurine hadrosaur on the basis, among other characters, of its massive supracetabular process and its strongly curved preacetabular process. Besides the possible lambeosaurine Pararhabdodon from Lleida province, also found in the South Central Pyrenees, the Blasi 3 ilium represents a new good evidence of a lambeosaurine dinosaur presence in Europe the end the Cretaceous
Migmatization of the basal paragneisses of the Filali Unit (Beni Bousera Massif, Morocco) during polyphase extensional tectonics
(Sociedad Geológica de España, 2005) Aghzer, A. M.; Haissen, F.; Afiri, A.
Los paragneises basales de la Unidad de Filali registran dos episodios migmatíticos: (a) un episodio de media-presión (710-810°C y 6.6-9 kbar) relacionado con el colapso extensional tardi-Varisco que afectó a la sección litosférica de los Sebtides inferiores; y (b) un episodio de baja-presión de edad Alpina, que produjó cordierita durante una descompresión casi isotérmica (640-760°C y 4.5-5 kbar), asociado a la apertura durante el Oligoceno superior-Mioceno del dominio de Alboran
Microestructuras, diagénesis y evidencias estacionales en las valvas de Crassostrea sp. del Albiense superior-Cenomaniense inferior en la playa de Somocuevas (Liencres, Cantabria)
(Sociedad Geológica de España, 2005) Higuera Ruiz, R.; Elorza, Javier
The microstructural and cathodoluminescence (CL) study of Crassotrea sp. shells of Somocuevas, Cantabria (Upper Albian-Lower Cenomanian) has allowed to determinate that the dominant diagenetic process involved in the shells has been freatic meteoric, with cementación process in the pores and preservation of the initial microstructure of the oysters. The main microstructures are: Regular simple prismatic (RSP), Regular foliated (RF) and Complex cross foliated (CCF). These microstructures present a variable luminescence. The RSP exhibits a yellow-bright luminescence. The RF is not luminescent or presents a dull red luminescence, and the CCF has a medium to bright yellow luminescence. It is also observable the presence of dark growth lines with yellow bright luminescence in the RF, that are related with fractures in the umbo zone. It is proposed that these zones indicate anual growth lines that can be used to determinate seasonality
Los mamíferos del Pleistoceno Medio de la Cueva de los Huesos de Obón (Parque Cultural del Río Martín, Teruel)
(Sociedad Geológica de España, 2005) Cuenca Bescós, G.; Alberdi, M. T.; Canudo, José Ignacio; García, N.; Gordillo, J. C.; Made, J. V. D.; Ramón del Río, Diana; Rubio, C. J.
The Middle Pleistocene coincides with an important climate change, from this time ahead, the 100ky glacial cycles become a dominant feature. The opening of the landscapes, and a series of dispersal events of prairie taxa as the microtines, cricetids, ungulates and carnivores as well as Homo heidelbergensis mark this event. The rareness of fossil faunas of this age makes the Cueva de los Huesos de Obon one of the most important localities of this age in Aragon. Here we provide the first account on the Middle Pleistocene mammals from the Cueva de los Huesos, Obon, Teruel. The fossil mammalian species recovered in Obon are: Canis lupus, Vulpes vulpes, Felis sylvestris, Meles meles Hyaenidae and Carnivora indet., Stephanorhinus cf. hemitoechus, Equus sp. Gr. E. mosbachensis, Cervus elaphus priscus, Hemitragus sp. Erinaceus europaeus, Rhinolophus sp., Allocricetus bursae correzensis, Apodemus sp. This association is somewhat similar to that in the Trinchera Galería, Trinchera Dolina 8b-11 and Sima de los Huesos localities of Atapuerca
Los foraminíferos bentónicos del horizonte glauconítico inferior de la Formación «Arcillas de Gibraleón» (Depresión del Guadalquivir, SO España)
(Sociedad Geológica de España, 2005) González-Regalado Montero, María Luz; Ruiz Muñoz, Francisco; Abad de los Santos, Manuel; Pendón Martín, José Gabriel; Tosquella Angrill, Josep
This paper analyzes the benthic foraminiferal assemblages present in two Upper Tortonian sections belonging to the «Arcillas de Gibraleón» Formation (Guadalquivir Basin) containing a characteristic glauconitic level. The basal samples of this horizon show both shallow-water and epibathyal taxa, a mixture also found in ostracods that may characterize the transition toward deeper conditions. In the upper samples, deepneritic and epibathyal species are dominant, indicating a moderate-deep environment (150-300 m) in which was deposited most of the glauconitic horizon

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