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X Congreso Geológico de España, 5-7 Julio 2021, Vitoria - Gasteiz, El análisis de la geometría y cinemática de estructuras oblicuas es necesario para entender su origen y evolución. En este trabajo el estudio de la fábrica magnética se utiliza como una herramienta para determinar la historia deformacional de los pliegues oblicuos situados en el autóctono deformado del sector nororiental de la cuenca de antepaís del Ebro. Un total de 149 estaciones han sido analizadas a partir del análisis de la fábrica magnética (anisotropía de la susceptibilidad magnética) con este objetivo. El muestreo se realizó en materiales detríticos sinorogénicos del Eoceno Superior-Oligoceno del sector de Artesa de Segre-Cardona. A pesar de la dirección de acortamiento regional aproximada N-S, oblicua con respecto a la orientación N045E a N135E de los pliegues estudiados, las direcciones obtenidas de la lineación magnética en la mayoría de los casos se encuentran contenidas en el plano de estratificación y paralelas a los ejes de los pliegues oblicuos. El análisis paleomagnético realizado de forma paralela a este estudio muestra la existencia de rotaciones anti-horarias de estos pliegues relacionadas con el emplazamiento del saliente de cabalgamientos del Pirineo Central (Peigney et al., 2021), lo que sugiere que los elipsoides magnéticos obtenidos han actuado como marcadores pasivos de la deformación registrando información relacionada con el acortamiento paralelo a las capas inicial (layer parallel shortening) y/o su plegamiento posterior.

Màster de Meteorologia, Facultat de Física, Universitat de Barcelona, Curs: 2020-2021, Tutor: Joan Bech, The objective of this work is to study rainfall characteristics (frequency, amount and type) in a semi-arid region in the Eastern Ebro basin (Iberian Peninsula). The region is included approximately in a 20 km per 30 km rectangle and is divided in two different areas, one irrigated with an artificial channel, and another one non-irrigated. The two areas may present a big difference of surface temperature in a short distance, particularly during midday hours of summer months due to high evapotranspiration contrasts. The study focusses in finding possible differences in rainfall characteristics between two areas. The methodology used is based on the analysis of radar reflectivity data, which is processed to determine the rainfall type, classified in convective and non-convective, a part of rain occurrence and amount. The work examined June, July and August data from years 2014 to 2020 analysing daily, monthly and total rain events distributions in both areas. The results show a big variability of the rainfall in the region depending on the year and as expected, an increase in convective rain in both areas during the afternoon. Although there is not a significant difference in the rainfall type nor in the convective rainfall rate between areas, there is a difference in the convective rain distribution along each area, being the rain in the irrigated part less homogenous than the non-irrigated part. This study has been performed in the framework of the Analysis of Precipitation Processes in the Eastern Ebro Subbasin project (WISE-PreP, RTI2018-098693-B-C32/AEI).

Dating the sedimentary infill of the northern margin of the Ebro foreland basin informs about the orogen-basin evolution. A magnetostratigraphic section of ~5 km-thick combines new magnetostratigraphic results from the syntectonic alluvial Uncastillo Fm (Upper Oligocene-Lower Miocene, 1 km-thick, the Fuencalderas section) with previous (3.3 km-thick) and new (0.7 km-thick) magnetostratigraphic data from the underlying fluvial Campodarbe Fm (Luesia and San Marzal sections, Eocene-Oligocene). This composite section allows dating the entire basin infill in this sector, therefore bracketing the timing of the deformation in the southern margin of the Pyrenees after considering previous kinematic studies. Deformation recorded by the continental deposits spans from syn-Gavarnie nappe activity (Broto and Fiscal basement thrust sheets) from 31.3 to 24.55 Ma, Rupelian-Chattian (Oligocene) to the syn-Guarga thrust activity, from 24.55 to 21.2 Ma Chattian-Aquitanian (Oligocene-Miocene). The Accumulation rates vary from ca. 22 to ca. 39 cm/kyr between the genetic stratigraphic units in the Uncastillo Fm through the section. These rates are close to those of the underlying deposits of the Campodarbe Fm (average of ca. 36 cm/kyr). Deformation for the latest Pyrenean front (syn-Guarga thrust) is younger than previously assigned in ~5.4. ~1.5 and ~1.1 Myr of the beginning of the Punta Común thrust sheet (from 29.4 Ma to 24 Ma), Lower Riglos thrust sheet system (from 24 to 22.5 Ma) and the Upper Riglos thrust system (22.5 to 21.4 Ma) respectively. Other significant changes in accumulation rate and its derivative also indicate variations in the tectonic activity ca. 33 and 28 Ma. © 2019 Elsevier B.V., Financial support was provided by the Spanish Ministry with the SEROS project, reference: CGL2014-55900-P/BTE and the project DR3AM-CGL2014-54118-C2-2-R. Thanks to the Paleomagnetic Laboratory CCiTUB-ICTJA CSIC, the Geomodels Research Institute, the Grup de Geodinàmica i Anàlisi de Conques - 2017SGR00596 and Geotransfer Group at the University of Zaragoza.

Adequate characterization of depositional architecture is of great importance when studying fluvial outcrops as reservoir analogs. The complex three-dimensional (3D) distribution and lateral and vertical relationships of sandstone bodies require a high degree of stratigraphic control in order to make a proper assessment of the distribution and connectivity of the reservoir facies. This assessment demands the use of reliable correlation datums. Unfortunately, clear marker beds (e.g., ash layers, coal beds, and paleosols) are not always available in fluvial outcrops, and when present, they are often covered by vegetation or debris that prevents their tracking over long distances. A new method to achieve highly accurate and semiautomatic correlations within fluvial digital outcrop models (DOMs) is presented in response to the need for further correlation procedures, especially in the absence of suitable datums. The method is based on the hypothesis that the average depositional paleosurface of a sedimentary system can be represented by a plane at outcrop scale. If this assumption is valid, this plane can be used as a virtual datum to identify along the DOM the sediments that were deposited simultaneously. The method was tested and applied successfully within two kilometer-scale outcrops of the Huesca fluvial fan (Early Miocene, northern Spain), where the virtual datum provided accurate correlations regardless of stratigraphic or topographical complexities. Moreover, all the sedimentary successions of the outcrops could be automatically subdivided into the desired stratigraphic intervals by only moving the virtual datum vertically. These intervals can be subsequently isolated to facilitate the detection of subtle variations and trends of their fluvial properties. Consequently, a virtual datum is the equivalent of having a marker bed crossing the stratigraphic succession of an outcrop at any desired position. The advantages provided by a virtual datum prove to be especially useful in large and topographically complex outcrops that previously could not have been studied with such a high degree of 3D stratigraphic control.

Chert from the limestones and marly limestones of Castelltallat Formation (Ebro Basin) was widely used throughout prehistoric times in north-eastern Iberia to produce stone tools due to its properties and accessibility. A rough estimate indicates that this rock—either as raw material or as lithic products—was distributed mainly to the north of the outcrops, over an area of 6000–8000 km2. However, other rocks in the area have similar characteristics which can lead to confusion in the interpretation of its prehistoric use and distribution. In order to establish useful archaeometric criteria for differentiating this chert from other similar, the Castelltallat chert is characterised in petrographic, mineralogical and geochemical terms. The chert nodules are found to be homogenous at the macroscopic and microscopic level, with a significant presence of bioclasts, thus indicating they might be formed in a freshwater lake environment by the early diagenetic replacement of carbonates in shallow waters. The mineralogical composition is homogeneously uniform and of a flint type, characterised by an almost exclusive predominance of quartz, without any opaline phases, and a variable proportion of moganite. The iron oxide content is very low, whereas its chemical composition is unusually high in uranium which correlates positively with carbonate content and negatively with silica. Archaeometrical parameters are provided to reach a proper identification of tools knapped with this chert. This way, chert from Castelltallat Formation turns out to be a valuable lithological marker to evaluate the range of mobility of the human groups who lived in the north-eastern Iberia and their contacts with neighbouring areas., The fieldwork to obtain rock samples and the analysis of the samples was cofunded by the Direcció General del Patrimoni Cultural de la Generalitat de Catalunya and IMF-CSIC, within the framework of an interinstitutional collaboration agreement for the development of the Catalan Lithotheque of siliceous rocks (LITOcat project). Specific studies on the petrological characterisation of Castelltallat chert and its prehistoric use were carried out within the research project ‘Aprofitament prehistòric i històric del sílex a Catalunya: contextos extractius i de primera transformació’, funded by the Department of Culture of the Government of Catalonia (ref. núm. 2014/100778). The significance of human use and scope of distribution of Castelltallat chert are being approached within the project ‘Productions, technical variability and technological innovation in the Neolithic’, funded by the Spanish Ministry of Economy and Competitiveness (Grant HAR2016–76534-C2–2-R).

Southern Pyrenean frontal thrusts are usually blind or partially covered by syn- and post-tectonic sediments of the Ebro Foreland hampering their interpretation. We have investigated the geometry and evolution of the Súria Anticline, a frontal structure of the Southern Pyrenees, which is characterized by the presence of multiple buried and blind thrusts displaying a complex triangle zone and several fishtail structures at depth. To characterize the geometry and structural evolution, a combination of surface geology, subsurface data interpretation, and analog modeling have been integrated into a unique 3D geologic model. The surface geology of this area depicts a rather simple structure, characterized by a north-directed backthrust and a gentle anticline, both striking west–southwest/east–northeast. In contrast, geophysical data indicate that the subsurface structure is more complex, exhibiting several northward- and southward-directed thrusts and folds detaching on the Pyrenean foreland Eocene evaporites. Integration of surface (geologic maps and dip measurements) and subsurface data (seismic and wells) allowed us to reconstruct the 3D structure of this area. To produce a more robust kinematic model, we used an experimental approach to investigate the evolution of frontal structures in folds and thrust belts on evaporitic detachments. Different viscous layer configurations were tested in a series of sandbox models comparing them with the evolution of the Súria Anticline. Taking into account the deformation and that seismic quality is in general poor, the experimental results allow us to better characterize the structures developed in this area. Our structural evolution is characterized by an early stage of salt inflation and fold nucleation. With increasing shortening, the structure evolved to a detachment anticline eventually developing a northward-directed thrust that broke through the northern anticline limb. The present-day geometry developed in a later stage of fold reactivation, when a new regional fold formed, and tightened the preexisting structure.

En cinturones de pliegues y cabalgamientos con niveles evaporíticos es típico el desarrollo de pliegues de adaptación de falla y de despegue. La geometría de estas estructuras, su cinemática, y sus propiedades mecánicas han sido ampliamente analizadas. Sin embargo, gran parte de la literatura existente se ha centrado en el estudio de los niveles evaporíticos pre-cinemáticos sin discutir el rol de los niveles evaporíticos depositados durante la deformación contractiva cuando, en realidad, son comunes en cuencas de antepaís deformadas (p.e., Cuenca de Tarim o Zagros, o Cuenca del Ebro entre otras). Este trabajo se centra en la caracterización de la estructura de una zona del frente surpirenaico central mediante la realización de una cartografía geológica de detalle apoyada en un corte geológico compensado. El objetivo es mostrar el papel que han tenido los niveles evaporíticos sin-orogénicos (Paleogeno) en la geometría y evolución cinemática del frente surpirenaico central. Los resultados muestran que la terminación meridional de la sal sin-orogénica de la Fm. Cardona controla la posición del pliegue de despegue de Sanaüja. Y en la terminación meridional de los yesos sinorogénicos de la Fm. Barbastro se forma una estructura tipo cola de pez que en superficie se corresponde con el pliegue de adaptación de falla de La Sentiu - Almenara.

La Plana de Vic, situada hacia el sector NE de la Cuenca del Ebro, se caracteriza por un espeso apilamiento de materiales marinos que fueron acumulados principalmente durante el Paleógeno. Sobre una discordancia desarrollada sobre el basamento paleozoico se acumularon materiales aluviales distales de granulometría fina (Taneciense) que quedaron recubiertos por una delgada cuña marina (Ilerdiense). Encima existen materiales aluviales distales de granulometría fina que pasan gradualmente a otros de granulometría gruesa, que en su parte superior muestran intercalaciones de areniscas y carbonatos con Nummulites y Assilina (Luteciense). Posteriormente, se depositaron lutitas de offshore que soportaron la progradación de materiales arenosos costeros. En la parte central de la cuenca siguió la acumulación de lutitas (Bartoniense) que a su vez fueron afectadas por progradaciones deltaicas en los sectores meridionales y septentrionales. A techo de algunos cuerpos deltaicos se depositaron litosomas arrecifales carbonatados. Sobre una discontinuidad sedimentaria aparece una acumulación compleja de lutitas, areniscas, evaporitas y carbonatos donde se hallan los nuevos yacimientos de peces fósiles (Priaboniense). Entre los especímenes se han identificado algunos Clupeidos, Percofórmidos y Synodontidos que representan los últimos episodios de la sedimentación marina en la zona durante el Eoceno The Plana de Vic is located towards the NE of the Ebro Basin and is mainly characterized by a thick pile of marine sediments that accumulated along the Palaeogene. Overlying a Palaeozoic basement and a marked unconformity are fine-grained non-marine materials (Thanetian), which are covered by the accumulation of a thin marine wedge (Ilerdian). These marine materials were subsequently overlain by fine- and coarse-grained alluvial deposits. Towards the upper part of these alluvial deposits are sandstones and limestones with Nummulites and Assilina. Thereafter, lutitic materials deposited offshore were covered by the prograding coastal sandy materials. In the central part of the basin the accumulation of offshore lutites continued (Bartonian). These lutites were affected by the southwards and northwards deltaic progradations. Limestonedominated reefs were deposited over the deltaic bodies. On top of the sedimentary unconformity is a complex accumulation of lutites, sandstones, evaporites and limestones (Terminal complex) containing the remains of the fossilized fish (Priabonian). Some specimens of Clupeids, Percoformids and Synodonts represent the last episodes of the Eocene marine sedimentation in the study area

The results of anisotropy of magnetic susceptibility analyses of 19 sites carried out on magnetostrigraphically-dated, Lower to Middle Miocene (20.4 to 13.7 Ma) “non-deformed” mudstones from the central part of the Ebro basin reveal the presence of a subtle tectonic overprint lasting at least until the Langhian (Middle Miocene) in the southern Pyrenean foreland. Magnetic ellipsoids show a sedimentary fabric in 42% of sites and a weak and well-defined magnetic lineation in 47% and 11% of sites. The magnetic lineation is roughly oriented around the east–west direction, compatible with a very weak deformation occurring there and related to the north–south compression linked to the convergence between Europe, Iberia and Africa during the Early–Middle Miocene. A slight variation of the magnetic parameters Km, Pj, and T exists through time, probably due to changes in the sedimentary conditions in the basin., Funding for this work came from project CGL2013-42670-P (Ministry of Economy and Competitiveness, Spain) and a JAE-Doc Postdoctoral (CSIC, Spain) contract for the first author.

Las nuevas técnicas de recolección de datos digitales surgidas en los últimos años han dado lugar a avances significativos en el campo de la caracterización de afloramientos. Esta evolución se basa en la premisa de que cuanto mayor sea la cantidad, la calidad (exactitud), y la velocidad de recolección de los datos, mejores serán las interpretaciones y modelos que se deriven de ellos. Una de las técnicas más recientemente incorporadas en el estudio de afloramientos geológicos es el escaneo láser terrestre (TLS), el cual se basa en la tecnología lidar (desarrollada en la década de 1960). El objetivo principal de esta tesis es aprovechar el potencial del TLS para desarrollar nuevas herramientas y metodologías que permitan resolver la principal limitación a la que se enfrentan los geólogos cuando trabajan en afloramientos fluviales: adquirir el control estratigráfico necesario para detectar, comprender y caracterizar el alto grado de heterogeneidad en el espacio y el tiempo que muestran las sucesiones fluviales. Con este propósito se han adquirido datos con TLS en 8 afloramientos del Abanico Fluvial de Huesca (Mioceno inferior, norte de España). Se han utilizado softwares comerciales para procesar las nubes de puntos adquiridas y así obtener Afloramientos Virtuales (VO’s), pero la mayor parte de los logros obtenidos de su estudio fueron posibles gracias softwares desarrollados en la propia facultad. Por otro lado, también se han medido varias columnas estratigráficas detalladas y se recogieron muestras litológicas de diferentes tipos de cuerpos areniscosos. En base a estos datos y a las observaciones realizadas sobre el terreno los resultados más relevantes obtenidos son los siguientes: * Una caracterización detallada de las facies fluviales, la cual incluye el estudio de las propiedades petrológicas y petrofísicas de los cuerpos areniscosos. * Un método simple que se sirve del VO para corregir las alturas y espesores de los cuerpos sedimentarios medidos en las columnas estratigráficas. Los principales factores que pueden haber influido en las mediciones realizadas con Vara de Jacob han sido estudiados y discutidos. * Se ha establecido un nuevo método que permite realizar correlaciones semiautomáticas y altamente precisas en los VO’s de afloramientos fluviales, el cual se basa en la hipótesis de que el paleosuperficie deposicional del sistema sedimentario puede ser representada por un plano a escala de afloramiento. Si esta suposición se cumple en el afloramiento, este plano puede ser utilizado como un datum virtual para identificar a lo largo del VO los sedimentos que fueron depositaron simultáneamente. El método ha sido probado y aplicado con éxito en cuatro afloramientos de escala kilométrica del Abanico Fluvial de Huesca, en los cuales los datums virtuales han proporcionado correlaciones precisas independientemente de las complejidades estratigráficas o topográficas de los mismos. Además, únicamente con mover el datum virtual se puede subdividir toda la sucesión sedimentaria de los afloramientos en los intervalos estratigráficos deseados, los cuales pueden ser aislados del resto para facilitar su estudio en detalle. * Los datums virtuales también se han utilizado como base para establecer un nuevo procedimiento que permite inferir cuales son las posiciones estratigráficas relativas dentro de toda la secuencia fluvial de afloramientos que distan decenas de kilómetros. * Se ha realizado una modelización estocástica de facies basada en objetos que se sirve de los datos obtenidos al aplicar un nuevo método para extraer de una manera semiautomática las superficies del VO que pertenecen a paleocanales. Los flujos de trabajo de modelización de análogos habituales utilizan los datos de columnas estratigráficas (en forma de pseudopozos) para condicionar las simulaciones, pero con el método presentado aquí toda la superficie del afloramiento es considerada para este propósito, aumentando significativamente de ajuste del modelo a la realidad. Gracias a la utilización de la tecnología lidar en afloramientos del Abanico Fluvial de Huesca se han conseguido establecer diferentes métodos de trabajo que han demostrado ser útiles de cara a facilitar y mejorar la construcción de modelos de análogos de reservorio. Además, se considera que su aplicación puede sin duda contribuir a mejorar nuestra comprensión de los factores y mecanismos que influyeron en la evolución de los sistemas sedimentarios fluviales antiguos., Terrestrial laser scanning (TLS) is based on lidar technology, which although developed in the early 1960s, has only recently been incorporated into the study of geological outcrops. The main aim of this thesis is to take advantage of the potential of the TLS to provide new tools and methodologies focused on solving the main limitation found by the geologists when working in fluvial outcrops: acquire the degree of stratigraphic control required to detect, understand and characterize the high degree of spatial and temporal heterogeneity of fluvial successions. TLS data from 8 outcrops of the Huesca Fluvial Fan (Early Miocene, northern Spain) were acquired to this purpose. In addition, several detailed stratigraphic columns were measured and lithological samples from different types of sandstone bodies were collected. Based on this, the most relevant results obtained are as follows: * A comprehensive characterization of the fluvial facies that includes the petrological and petrophysical properties of the sandstone bodies. * A simple method using the VO to correct the heights and thicknesses of the sedimentary bodies measured in the stratigraphic columns. The main factors that may have influenced the measurements made with the Jacob’s staff have been studied and discussed. * A new method leading to obtain a virtual datum is presented in response to the need for further correlation procedures, especially in the absence of suitable datums. This virtual datum enables to achieve highly accurate and semiautomatic correlations within fluvial VO’s. Moreover, all the sedimentary successions of the outcrops can be automatically subdivided into the desired stratigraphic intervals (which can be later isolated) by only moving the virtual datum vertically. * The virtual datums were also used to establish a new procedure that leads to infer the relative stratigraphic positions of distant outcrops (more than 10 Km apart) inside the entire fluvial sequence. * A facies modelling has been performed using a new method to extract in a semiautomatic way the surfaces of the outcrop that belong to paleochannel exposures.

Glauberite (Na2Ca[SO4]2) is an evaporitic mineral which is used in the industries of detergents, paper, glass, pharmacy, etc. Glauberite rocks are seldom found cropping out because they are very sensitive to weathering processes; for this reason their prospection is conducted by means of boreholes. Nowadays, geophysical techniques are not used to support the characterization of glauberite deposits due to the lack of knowledge of their physical properties. In this study geoelectrical methods are proposed as alternative techniques in the early stages of glauberite prospecting. Several glauberite units have been studied in different parts of the Ebro basin (Spain) by means of electrical resistivity tomography sections. The electrical resistivity range showed by glauberite deposits has been found to be low (10-100 Ω.m) when the matrix component (clay andmicrocrystalline carbonates) is above 45% of the bulk composition of the rock. This type of rocks has been studied in Montes de Torrero (Zaragoza) and is the most common glauberite deposit case. Besides matrix-rich glauberite rocks, an exceptional case of a pure glauberite layer has been studied in Alcanadre (La Rioja). From this site, it has been estimated that deposits with glauberite crystals fraction close to 100% show a resistivity range of at least 3×103 Ω.m. Using this extreme value as reference, the Hashin-Shtrikman bounds have been calculated for glauberite rocks considering that they are constituted of four phases (glauberite, gypsum, anhydrite and matrix). When the matrix fraction represents 45% or more of the bulk rock, the resistivity range will be that of the lower Hashin-Shtrikman bound, which is similar for any combination of sulphate (glauberite, gypsum and/or anhydrite) composition; hence, it can be considered as a two-phase system (matrix and sulphate). For rocks with less than 30% of matrix fraction, the upper Hashin-Shtrikman bound trend must be considered; however, the resistivity values overlap, making it impossible to establish a classification. Between 30 and 45% of matrix fraction, there is a transitional domain. Additionally, some theoretical models representing the most common structures in sulphate rocks have been elaborated in order to help in the interpretation of the inverted resistivity images obtained from the field data. Some artifacts generated by the complexity of the resistivity distribution of the terrain have been identified in both data sets. Keywords: Glauberite, Gypsum, Electrical Resistivity Tomography, Karst

Aquesta tesi doctoral té com a objectiu principal la caracterització taxonòmica, paleoecològica, paleobiogeogràfica i biostratigràfica dels caròfits de l’Eocè superior-Oligocè inferior de la Conca de l’Ebre. La flora de caròfits de l’Eocè superior-Oligocè inferior del marge est de la Conca de l’Ebre està constituïda per Sphaerochara labellata, Chara aff. antennata, C. artesica n. sp., C. rhenana, C.microcera, Psilochara aff. acuta, Lamprothamnium sp., Gyrogona caelata, Nodosochara jorbae, Lychnothamnus longus, L. stockmansii, L. grambastii, L. vectensis, L. pinguis (=L. major), Nitellopsis (Tectochara) merianii, Harrisichara lineata, H. vasiformis-tuberculata i H. tuberculata. En totes es caracteritza el polimorfisme intraespecífic a parti d’un estudi biomètric dels girogonits. Des d’un punt de vista taxonòmic se sinonimitzen, a partir de les poblacions tipus, dues espècies clau en biostratigrafia del límit Eocè-Oligocè europeu, Lychnothamnus pinguis i L. major. L’anàlisi paleoecològica de les associacions de caròfits de l’Eocè superior al sector NE de la conca de l’Ebre ha permés determinar que espècies clau per la biostratigrafia del límit Eocè-Oligocè presenten clares limitacions paleoecològiques. Així, Harrisichara vasiformis-tuberculata creixeria només en ambients salabrosos i soms pròxims a la costa, Harrisichara lineata es relaciona amb llacs soms d’aigua dolça i Harrisichara tuberculata abunda, però no és exclusiva, de llacs perennes i profunds d’aigua dolça. Altres espècies com Sphaerochara labellata, Lychnothamnus stockmansii, L. pinguis (=L. major) i Chara microcera es troben en llacs permanents. En conclusió, la presència o absència d’aquestes espècies, i per tant, de les biozones homònimes en una determinada conca europea depèn del tipus de fàcies i del paleoambient associat mes que no d’esdeveniments evolutius. Altres espècies com Lychnothamnus vectensis, Nodosochara jorbae, Lychnothamnus longus o Chara artesica n. sp., en canvi, no presenten cap limitació ecològica important dins el context dels sistemes aquàtics continentals. L’anàlisi paleobiogeogràfica de la caroflora de l’Eocè superior-Oligocè inferior d’Europa permet identificar una polaritat latitudinal en la distribució i abundància de les espècies. No obstant, partint de les espècies comunes a totes les conques europees es defineix una bioprovíncia europea per l’Eocè superior-Oligocè inferior la qual es pot caracteritzar a partir dels llinatges Harrisichara vasiformis-H. tuberculata i Lychnothamnus stockmansii-L. major així com de les espècies Nitellopsis (T.) merianii i Chara microcera. Les variacions regionals d’aquesta flora responen a factors climàtics locals i a factors ecològics lligats a la dinàmica de cada conca. La distribució biogeogràfica de determinades espècies, com Sphaerochara labellata o L. pinguis ha mostrat que l’us d’aquestes especies en biostratigrafia està condicionada per factors paleogeogràfics. L’anàlisi de la biogeografia històrica del llinatges evolutius Lychnothamnus stockmansii-L. major i Nitellopsis(Tectochara)merianii-N. obtusa suggereix que les espècies de caràcies fòssils seguien diferents patrons de dispersió en funció de la disposició dels seus gametangis (dioica vs. monoica). És clar que les espècies monoiques com Lychnothamnus stockmansii-L. major, amb velocitats d’expansió geològicament instantànies, són idònies alhora de correlacionar biostratigraficament conques allunyades. Des d’un punt de vista biostratigràfic, les associacions de caròfits han permès precisar l’atribució biostratigràfica de les unitats litostratigràfiques estudiades. S’ha proposat una biozonació de carofits per la conca de l’Ebre a partir d’espècies ecològicament euritípiques. Aquesta biozonació s’ha correlacionat amb la biozonació local de vertebrats i s’ha calibrat amb la magnetostratigrafia definida a l’est de la conca per Barberà et al. (2001) i Costa et al. (2010, 2011). La nova proposta permet caracteritzar el límit Eocè-Oligocè dins la biozona de Lychnothamnus vectensis. A més, s’ha revisat la biozonació europea avui dia en us. La calibració dels límits de les biozones europees amb l’escala del temps absolut mitjançant la magnetostratigrafia ha permès, per primera vegada, precisar la durada temporal de les biozones de caròfits del límit Eocè-Oligocè.

The onset of endorheic sedimentation in the Ebro Basin is a prominent feature of the basin's evolution and has recently been characterized as a rapid event occurring in the Early Priabonian. In the north-eastern part of the basin this event coincides with the deposition of the Artés Formation (Fm.), mainly built up by red beds of alluvial origin. The marine-continental boundary has been poorly studied up to now in the so-called Lluçanès area, and what was previously thought to be the base of the Artés Fm. is actually a transitional unit, which we define as the Sant Boi Formation, which covers the underlying marine Milany Depositional Sequence and passes laterally to the Terminal Complex, extending over 15km along the eastern margin of the Ebro Basin. The Sant Boi Fm. is formed by up to 15-20m of alternating siltstones and lutite, grading upwards to brackish and lacustrine marls and lignite, and represents deposition in a brackish to freshwater floodplain. It is characterized biostratigraphically by the fossil charophyte assemblage Harrisichara lineata, Harrisichara vasiformis-tuberculata and Nodosochara jorbae, from the middle part of the Priabonian. In contrast, the overlying red beds of the Artés Fm. are characterized by assemblages containing Harrisichara tuberculata, Nodosochara jorbae and Lychnothamnus longus from the Late Priabonian. These results are largely consistent with recent magnetostratigraphic studies performed south of the studied area, and have enabled us to refine the stratigraphy of the marine-continental transition in the north-eastern Ebro Basin.

[eng] This PhD-Thesis presents a new chronostratigraphy of the Paleogene sedimentary record of the SE margin of the Eastern Ebro Basin. It is based on a number of magnetostratigraphic sections and its integration with marine and continental biochronological data. A robust correlation with the geomagnetic polarity time scale is obtained and provides the record with absolute ages, spanning from chrons C20n to C12r (Lutetian to Rupelian stages, ca. 43.0-31.0 Ma). Main differences with respect to the current chronostratigraphic scheme of the Eastern Ebro Basin include the age of the uppermost marine units. While earlier schemes attributed a Bartonian age to these units regarding its biostratigraphical contents, new results supports a Lower Priabonian age, yielding an interpolated age of ca. 36.0 Ma (within chron C16n.2n) for the continentalization process. This age is in concordance with a reinterpretation of earlier magnetostratigraphic data from the Western South Pyrenean Foreland Basin, and indicates that continentalization of the basin occurred as a rapid and isochronous event. The analysis of the observed sedimentation trends are used to evaluate the character of this process. Thus, contrasting sedimentation trends between the Western and Eastern sectors of the South Pyrenean foreland are proposed to indicate that basin closing preferentially affected those areas subjected to sediment bypass towards the ocean domain. Moreover, new results provide improved temporal constraints for the sediments of the Eocene Montserrat alluvial fan and fan-delta complex. Thus a Lutetian age is ascribed to the whole La Salut Formation and the age of the Montserrat Conglomerates spans from Upper Lutetian to Lower Priabonian. The new chronological framework is used to unravel the forcing controls on the sequential arrangement of the Montserrat area at different temporal scales, and also to revise the tectonosedimentary history. Obtained results show a correlation between (tectonic) subsidence and forelimb rotation measured on deformed strata of Montserrat. Furthermore, integration of subsidence curves from different sectors of the Eastern Ebro Basin allows estimating the variable contribution of tectonic loads from the two active basin margins: the Catalan Coastal Ranges and the Pyrenees. The results support the presence of a double flexure from Late Lutetian to Late Bartonian, associated to the two tectonically active margins. From Late Bartonian to Early Priabonian the homogenization of subsidence values is interpreted as the result of the coupling of the two sources of tectonic load. Finally, the obtained chronology contributes to the calibration of several biostratigraphic zonations to the geomagnetic polarity time scale. In the marine realm, the base of calcareous nannofossil Zone NP19-20 is pinned down to an older age than its currently accepted attribution, whereas the time span assigned to Zone NP18 is significantly reduced. A revised calibration of larger foraminifers indicates that Zone SBZ18, formerly assigned exclusively to Late Bartonian, extends its range to the earlymost Priabonian, being the Bartonian stage almost entirely represented by Zone SBZ17. A division of Zone SBZ18 into two subzones is also proposed. In the continental realm, the magnetostratigraphic record of the Eastern Ebro Basin yields accurate ages for the immediately pre- and post-Grand Coupure mammal fossil assemblages found in this basin. Thus, the Grande Coupure, a major terrestrial faunal turnover recorded in Eurasia associated with the overall climate shift at the Eocene-Oligocene transition, is found to occur with a maximum allowable lag of 0.5 Myr with respect to this boundary. Furthermore, results from this PhD-Thesis allow revisiting correlations for the controversial Eocene-Oligocene record of the Hampshire Basin (UK), and their implications for the calibration of the Mammal Paleogene reference levels MP18 to MP21., [cat] Aquesta Tesi Doctoral presenta una nova cronologia del registre sedimentari Paleogen del marge SE del sector oriental de la Conca de l’Ebre. La cronologia obtinguda es basa en la integració d’un conjunt de sèries magnetostratigràfiques amb totes les dades biostratigràfiques dels registres marí i continental disponibles en aquest sector de la conca. L’establiment d’una correlació robusta amb l’escala de temps de polaritat geomagnètica proveeix al registre sedimentari Paleogen d’un marc cronològic amb edats absolutes que van des del cron C20n fins al cron C12r (ca. 43.0-31.0 Ma), és a dir, del Lutecià al Rupelià. Aquest nou marc cronològic proporciona les eines necessàries per a la quantificació i posterior comprensió de l’evolució tectonosedimentària dels marges adjacents a la Conca de l’Ebre. Finalment, la cronologia resultant de la present Tesi Doctoral contribueix a la calibració amb l’escala de temps geològic de les biozonacions de nanofòssil calcari i macroforaminífers (Shallow Benthic Zones), així com dels nivells de referència de mamífers paleògens europeus (European vertebrate Mammal Paleogene –MP- reference levels).

[cat] Els resultats que es presenten en aquesta tesi estan centrats bàsicament en l'estudi de la biodiversitat de les diatomees epilítiques presents en els rius de la conca de l'Ebre i en la seva aplicació com a indicadores de l'estat ecològic de les masses d'aigua. Durant els mesos d'estiu del 2005 i 2006 es va realitzar el mostreig de la flora de diatomees epilítiques en un total de 197 i 211 estacions, respectivament, pertanyents a la Xarxa de Control de l'Estat de les Masses d'Aigües Superficials (CEMAS) de la Confederació Hidrogràfica de l'Ebre (CHE). Aquests mostrejos van ser impulsats per la CHE amb l'objectiu d'establir xarxes de control biològic, basades en bioindicadors del fitobentos per tal de conèixer l'estat ecològic de les aigües fluvials d'acord amb el que estableix la Directiva Marc de l'Aigua (DMA). La recollida de les mostres, el seu tractament químic i, la quantificació de les espècies per localitat, s'han basat en les normatives estandarditzades europees CEN/TC 230 EN 13946:2003, norma prEN 14407: 2004 i, en els protocols de la CHE per l'avaluació de la qualitat biològica en rius mitjançant diatomees. L'examen de les mostres recollides ha permès la identificació de 499 tàxons, repartits en 91 gèneres, dels quals 492 han estat a nivell específic o infra-específic. Dels tàxons identificats, 361 estan representats en 751 fotografies realitzades al microscopi òptic, agrupats en 25 làmines. Com a particularitats de la flora s'esmenta d'una banda la presència de 7 espècies al•lòctones segons les consideracions principalment de Coste & Ector 2000 Achnanthidium catenatum, A. druartii, Diadesmis confervacea, Didymosphenia geminata, Gomphoneis minuta, Navicula kotschyi y Reimeria uniseriata) i per l'altre, la presència en algunes localitats de diverses formes teratològiques que podrien indicar condicions adverses del medi (estrès químic o contaminació), encara que en alguns casos podrien ser originades simplement per causes naturals. Com a resultat de la determinació de l’estat ecològic de les masses d’aigua s'ha comprovat l'aplicació i funcionament òptim dels índexs de diatomees (Index de Pol•lució Específica IPS, Index Biològic de Diatomees IBD i Index Europeu CEE), sent l'IPS l'índex més convenient per la bioindicació de l'aigua a la conca de l'Ebre. No obstant, aquests índexs no reflecteixen prou bé les diferències entre algunes ecoregions de la conca de l'Ebre, com ara les capçaleres calcàries. Tenint en compte els resultats obtinguts amb l'IPS, la proporció de localitats estudiades que complirien amb la DMA en aquests 2 anys d'estudi són bastant similars, seria del, [eng] "Diatoms of the Ebro basin: Biodiversity and ecological state of water" TEXT: The aim of this PhD thesis is to contribute to the taxonomic knowledge of the epilithic diatom flora from the rivers of the Ebro basin and to determinate the water quality status in the studied area using benthic diatoms as indicators. The studied area is located inside the Water Quality Surveillance Network of the Ebro Water Agency, CHE (NE Spain). It includes the Ebro and Garona rivers and all the rivers and streams which run into them in the Spanish territory, mostly over a calcareous and sedimentary substrata. A total of 408 epilithic diatoms samples were collected from different environments and ecoregions within the limits of the network of the Ebro Water Agency, CHE (NE Spain) during the summers of 2005 (197 sites) and 2006 (211 sites). Epilithic diatom were sampled, and then treated to prepare permanent diatoms slides following the standard methods (European Committee for Standardization 2003, 2004). The number of taxa identified in the material studied amounted to 499 (492 a specific or infra specific level), belonging to 91 different genera. 361 taxa are presented in 751 light microscope micrographs regrouped in 25 plates. We noticed the presence of species considered rare or exotic for European freshwaters (Coste & Ector, 2000) such as Diadesmis confervacea; Achnanthidium catenatum, Reimeria uniseriata, Navicula kotschyi, Gomphoneis minuta and Didymosphenia geminata. A few diatoms species presented teratological forms have been detected in some localities. However, we could not find a direct relationship of these forms occurrence and any particular cause. In order to evaluate the water quality assessment, three diatoms indices were applied (Specific Pollution Index IPS, Biological Diatom Index BDI and European Index CEC). All of them correlated significantly with water physical and chemical variables, but SPI achieved better correlations, and is therefore to be the best diatom index to be applied in the Ebro basin, although in some cases it did not properly reflected special situations in this basin as calcareous headwaters. According to the cluster and canonical correspondence analyses, nutrient enrichment (from the headwaters to the mouth), environmental variables and impacts were to be the most important variables structuring diatom communities in the Ebro basin.

[eng] The effects of the main anthropogenic impacts in the fluvial ecosystem of the lower Ebro River are evaluated along the five chapters of the present thesis, using the benthic macroinvertebrate community as a bioindicator. Different approaches are integrated in function of the type of stressor, considering mainly heavy metal and organochlorine pollution and hydrological alterations. These approaches focus on the taxonomy and biological traits of the community, and on the bioaccumulation of pollutants, population and life history studies on keystone species such as Ephoron virgo (Ephemeroptera: Polymitarcyidae). The results evidence a strong ecological response, and demonstrate that these effects act at different levels of organization, including communities, populations and individuals., [cat] Els efectes dels principals impactes antropogènics de l'ecosistema fluvial del tram baix del riu Ebre s'estudien al llarg dels cinc capítols d'aquesta tesi, utilitzant la comunitat de macroinvertebrats bentònics com a bioindicadors. Depenent del tipus d'estrès, tenint en compte principalment la contaminació per metalls pesants i organoclorats i les alteracions hidrològiques, s'han considerat diferents aproximacions. Concretament, l'estudi se centra en la taxonomia i els trets biològics de la comunitat, la bioacumulació de contaminants, i els estudis poblacionals i relacionats amb el cicle biològic d'espècies clau com l'Ephoron virgo (Ephemeroptera: Polymitarcyidae). Els resultats evidencien una resposta ecològica important, i demostren que aquests efectes actuen a diferents nivells d'organització, incloent comunitats, poblacions i individus.

Previous magnetostratigraphic studies focused in the Eocene successions of the eastern Ebro Basin have provided some absolute age for the basin infill. These results were based on some biostratigraphic constraints wich have been recently challenged. Our new results from the approximately 3000 m thick Montserrat and Maians-Rubió magnetostratigraphic sections have been integrated into the both marine and continental biochronology data, providing a more independent chronology. The resulting absolute chronology of the Montserrat-Rubió composite section represents about 10 My, covering the Lutetian to Rupelian (approximately 40.7 to 30.5 Ma). This leads to the re-evaluation of the age of the La Salut Fm. (Lutetian to Bartonian) and the Montserrat conglomerates (Bartonian to Priabonian). The last marine regression in the central part of the SE margin of the Ebro Basin yields an approximate age of about 36.0 Ma (Priabonian).

3D reservoir characterizations of analogues based on outcrop studies provide geological information that can be used for reducing uncertainty in subsurface reservoir modelling to predict interwell areas. 3D reservoir-scale models of a 133 m thick transgressive-regressive sequence (Vilomara composite sequence), in the Sant Llorenç del Munt fan-delta complex (Eocene, Ebro foreland basin), reproduce heterogeneity scales which potentially influence flow simulation predictions. Three scales were recognized and modelled: (a) transgressive and regressive tracts in which the sedimentary record is structured; (b) stacking and interfingering of facies belts and (c) sedimentary bodies which provide sedimentological variability along facies belts. In order to solve the different stacking trend of transgressive and regressive tracts by using different modelling strategies, models were compartmentalized into several sections by means of modelling bounding surfaces (maximum regression and flooding surfaces). The depositional trend of facies belts for each tract was reproduced considering the stacking angle and interfingering measures obtained from outcrop studies, while the last modelling step in this work describes the geometry, arrangement and spatial relations of sedimentary bodies observed in field. All these models are stochastic simulations built applying different statistics algorithms provided by Roxar Reservoir Modelling System.

The study of two late Oligocene-early Miocene stratigraphic sections of alluvial and shallow lacustrine facies in the SE Ebro Basin has enabled the establishment of a high-resolution magnetostratigraphy for the Oligocene-Miocene boundary. The studied samples include alluvial sandstones and mudstones as well as shallow lacustrine limestones. A total of 121 stratigraphic levels, with an average sample spacing of -2.5 m, were sampled in two sections, using a portable gasoline powered dril1 machine. Core samples were cut in the laboratory into two or three standard specimens of 2.54 cm diameter X 2.1 cm in length. A minimum of two specimens per site were thermally or AF demagnetized in 8-9 steps at intervals of 50°C or 30°C, and intervals of 2.5 mT and 5 mT, respectively. The magnetic polarity zonation of the sections have been correlated to the Geomagnetic Polarity Time Scale (GPTS) allowing the recognition of Chrons 9r, 9n, 8r and 8n in the Mina Pilar section, and Chrons 6Cr, 6Cn, 6Br, 6Bn and 6AAr in the Valcuerna section. On the basis of magnetostratigraphic correlation it is deduced an interval of sedimentation time of -1.6 Ma for the Mina Pilar section, and 1.7-1.9 Ma for the Valcuerna section.

According to its original definition, the Artes Formation is formed by the ensemble of continental, red mudstones and sandstones interbedded with conglomerates resting on top of the marine deposits of the Bartonian to Priabonian Santa Maria Croup. However, detailed mapping clearly shows that those marine rocks are laterally equivalent to distal alluvial fan facies of the "Artes type". On the basis of our present sedimentological knowledge these facies can not be differentiated from those forming the Artes Formation sensu stricto .Therefore, we propose a new definition for the entire formation that includes its subdivision into two members

During paleogene times the deformation area associated to the Vallés fault system developed a series of compressive structures. In itially there was theem placement of a succession of thrusts and folds affecting mainly the mesozoic cover, whose erosion led to the deposition of mesozoic cover derived monogenic breccias and conglomerates. Subsequently the emergence of an out of sequence thrust, involving mainly paleozoic basement rocks was recorded in the basin by a paleozoic derived monogenic breccia level. Later on, basement and cover derived poligenic conglomerates and breccias were deposited as a response to the erosion of a more heterogeneous source area. The movement of a second thrust plate involving basement and cover rocks folded and thrusted the mesozoic cover and the tertiary deposits of the Ebro basin margin

El complejo de abanico costero de Sant Lloren$ del Munt se encuentra en el margen sureste de la cuenca del Ebro, en el noroeste de España. Durante el Paleógeno, este margen de la cuenca estuvo sometido a unas condiciones de tipo transpresivo durante las que se desarrollaron una serie de pliegues, cabalgarnientos y failas de desgarre. Esta estructuración dió lugar a un bloque tectónicamente elevado constituido por materiales del zócalo paleozoico y la cobertera mesozoica que alimentaba una serie de abanicos aluviales y costeros, como el de Sant Lloren$ del Munt, que se desarrollaron en el borde de la cuenca del Ebro. El complejo de Sant Lloren$ del Munt presenta depósitos tanto subaereos como submarinos bien desarrollados, donde se han podido diferenciar cinco principales asociaciones de facies : abanico aluvial proximal, abanico aluvial distal/llanura de abanico costero, frente deltaico, talud deltaico/offshore y plataforma carbonática. Se han tomado 32 muestras de las facies marinas del Bartoniense para el estudio de su contenido palinológico y en 19 de éstas se han encontrado granos de polen triásicos. La mayor parte de las muestras con porcentajes altos de palinomorfos triásicos se corresponden con facies detríticas ligadas a períodos con importantes aportes sedimentarios. Se ha determinado la presencia de más de 15 palinomorfos triásicos diferentes, la mayoría de los cuales nunca han sido encontrados en las muestras tomadas en los materiales triásicos que afloran en areas relativamente cercanas a la aquí estudiada. Se han encontrado palinomorfos típicos del Kamiense y Nonense (Tnásico superior). Los materiales del Triásico superior debieron aflorar extensamente durante el Bartoniense en el actual Valles occidental. El área fuente del complejo de Sant Lloren$ del Munt estuvo constituida tanto por materiales del zócalo paleozoico como de la cobertera Triásica, alcanzando esta última un desarrollo mucho más importante de lo que se había deducido hasta el momento. Existe una relación entre los tramos de las secuencias (fundamentales y compuestas), el contenido en palinomorfos triásicos resedimentados y el grado de conservación del polen. Existe también una relación entre el tipo de facies y el contenido en palinomorfos triásicos resedimentados.

A charophyte biozonation of the Paleogene (Thanetian-Chattian) sequences of the Eastern Ebro Basin (NE Spain) is proposed. This biozonation has been based on an intensive sampling carried out on well correlated sections which included, in some cases, fossil mammal localities. Bothfacts haveresultedin agood chronostratigraphic control of the biozonation. One of the most noticeable contributions from this local point of view is the characterization of the Ilerdian in the continental Ebro Basin sequences by the Maedleriella lavocati biozone. Although in afirst approach this biozonation is intended to be local the new data in the Eastern Ebro Basin have enlarged the ranges of some widespread charophyte index species. These changes in the charophyte sp&ies ranges has led to suggest some remarkable modifications of the preexistin~ Riveline' s (1986) charophyte biozonationfor western Europe: 1) TheN. (T. ) thaleri biozone siaried in the Ilerdian and not in the Cuisian. 2) The definition of new Late Eocene (S. labellata) and Late Oligocene (H. lagenalis) biozones. 3) The enlargement of the range of severa1 species which has resulted in suppressionof the Chara notata biozone and in redefinition of Chara microcera, St. pinguis, St. vectensis and Sr. berdotensis biozones. From apaleogeographic point of view the global percentages of pluricontinental, european and iberian species of the Paleogene Eastern Ebro Basin charophyte record suggest some kind of isolation of the charophyte populations in NE Iberia. This isolation could be enhanced by paleogeographic constraints during Bartonian and Latest Priabonian to Stampian transition.

Four systems tracts have been distinguished in the uppermost Eocene-lower Miocene continental deposits of the northern margin of the Ebro basin. 1) The Satinar systems tract 5pper Pnabonian-Stampian) consists of an alluvial system (Salinar Fm) located in the north, that passes to playa-lake evapontes (lower Barbastro Fm) towards the foreland. The alluvial sediments are represented only by distal fan and alluvial plain facies which are in the footwall of the Sierras Marginales thrust. The top of the Salinar systems tract is inarked by lacustrine limestones that represerit the alluvial fan retre,at and a change to less saline conditions. 2) The Peralta systems tract (upperPriaboniiin?-Stampian) consists of srnall alluvial fans attached to the Sierras Marginales (Peralta Fm) that pass to playa-lake evaporites towards ;he foreland (upper Barbastro Fm). The alluvial facies are represented by calcareous conglomerates, that grade in a few kilometers to thin-bedded sandstones and mudstones. Evaporitic facies are represented by nodular and larninated gypsum. The top of the Peralta systems tract is also marked by an extensive body of lacustrine carbonates that represent a new alluvial fan retreat. 3) The Peraltilla systems tract (Stampian-Chattian) consists of small alluvial fans (Calasanz Fm), that show i;imilar characteristics to those of the Peralta I'rn but they interfinger distally with a large fluvial systern sourced in the axial Pyrenees (Peraltilla Fm). This fluvial fan consists of red overbank deposits with paleosoils, and channelized bodies, which are mostly conglomeratic in the Azanuy syncline and become sandy towards the southern limb of Barbastro anticline. This granulometric change is accompanied by a change in channel type, from typical braided to sinuouir or straight. The Salinar and Peralta systerns are contemporaneous with the emplacernent of the Sierras Marginales thrust sheet. The clastic sedirnents accumulated in a flexura1 trough that widens while the thrust propagates. As a consecuence, the saline lake facies expand towards the foreland. During the Peralta systerns tract a blind detachment located in the base of the Barbastro evaporitic formation propagated and started to fold the foreland. The Peraltilla systems tract is contemporaneous with the end of displacement of the Sierras Marginales thrust sheet and the rnain growth of the Peralta detachment anticline. However, these tectonic events were accompanied by a significant forelandward shift of the basin depocenter and a more homogeneous subsidence. 4) The Sarinena systems tract (Chattian-Aquitanian) is very similar to the Peraltilla one but it shows a marked southwards shift of the proximal facies. It consists of srnall fans of local provenance (Baells Fm) that interfinger distally with alarge fluvial fan (Sarinena Fm). The sedimentation of the Sariñenasystems tract is contemporaneous with the continued southward propagation of the detachment through the foreland evaporites, that creates new detachment folds (Barbastro and Altarriba anticlines, Azanuy syncline). An episode of out-of sequence thrusting generates small thrust-top basins on the Sierras Marginales, filled by the Baells conglomerates. The Sariñena systems tract accumulated in a wide foreland trough, with a strongly subsiding located in the Azanuy syncline.

El relleno sedimentario de edad Priaboniense superior-Chattiense del sector oriental de la cuencade antepaís del Ebro puede subdividirse en cinco secuencias deposicionales, definidas en base a los principales cambios paleogeográficos que afectaron alos sistemas aluviales y lacustres en la región. Tanto el desarrollo de estructuras tectónicas superficiales como los procesos de ajuste isostático regional son considerados como los principales factores de control de esta evolución sedimentaria. Los cinco sistemas lacustres reconocidos (La Noguera, L'Anoia, Segarra, L'Urgell y Los Monegros) muestran unas caracteristicas de extensión areal y desarrollo de facies fuertemente controladas por su situación respecto a las zonas de máxima subsidencia. Las tendencias megasecuenciales de cambio o de alternancia de deposición evaporítica y carbonatada, son atribuidas aquí tanto a posibles cambios climáticos como a cambios en la composición del área fuente. Estos fueron inducidos por la evolución tectónica de los margenes de la cuenca.

A preliminary report on the work developed in the last years in the continental beds in the Ebro basin is presented. The find of more than twenty new localities with micromammal remains and the new samplings in some older ones (Santpedor, Calaf, Tarrega, etc.) enable us the establishment of a continuous sequence with good stratigraphic control from the Upper Eocene (Sant Cugat de Gavadons) to the Lower Miocene (Sta. Cilia). Eleven range zones, covering the mentioned time span are defined: Theridomys golpeae, T. aH. aquatilis, T. calafensis, T. major, T. aH. major, Eomys zitteli, E. major, E. aft. major, Rhodanomys transiens, R. schlosseri and Ebromys autolensis. More intensive sampling, particularly between the Theridomys major and the Eomys zitteli zones, is needed in the future to arrive to a continuous section covering the whole Oligocene.

Un muestreo intensivo del clasico yacimiento de mamíferos fósiles de Santpedor ha dado como resultado la presencia de Theridomys aff. aquatilis, Gliravus aff. priscus, Eucricetodon atavus y Pseudoltinomys gaillardi. Esta asociación permite atribuir los niveles de yacimiento al Oligoceno inferior mas bajo (nivel de Hoogbutsel).

A partir del estudio estratigráfico y sedimentológico realizado sobre diversas sucesiones estratigráficas de origen lacustre y aluvial en el sector SE de la cuenca del Ebro se han diferenciado dos sistemas deposicionales aluviales (Scala Dei, de procedencia catalánide y Matarranya-Guadalope de procedencia ibérica) que se relacionan entre si y con un tercer sistema (de Los Monegros) desarrollado esencialmente en el ámbito central de la cuenca y caracterizado por un acentuado desarrollo de unidades lacustres. Los hallazgos de yacimientos de micromamíferos fósiles han permitido establecer tres grandes biozonas locales atribuibles en su conjunto al Oligoceno Superior y el Aquitaniense.

[ES] En el sector suroriental de la Cuenca del Ebro, la inclinación paleomagnética obtenida en las sucesiones aluviales oligocenas es considerablemente menor que la esperable, si se considera la paleolatitud de referencia calculada para esa región durante el Oligoceno. Este error de inclinación puede deberse a diversos factores, como el control hidrodinámica de las partículas magnéticas en el medio deposicional, la compactación diferencial del sedimento durante el enterramiento, o bien a la deformación tectónica. Este trabajo se ha centrado en su estudio en dos sucesiones dominantemente aluviales, donde previamente se había establecido su magnetoestratigrafia. Las litofacies aluviales y lacustres estudiadas se han agrupado en cinco grupos: areniscas grises, areniscas rojas y versicolores, limos rojos, lutitas rojas y calizas. Se ha demostrado la existencia de una correlación entre la abundancia de filosilicatos y el error de inclinación. De esta manera, las litofacies con un bajo porcentaje de filosilicatos (calizas y areniscas grises) presentan errores de unos 5", estadisticarnente no significativos, con respecto a la inclinación de referencia. Por el contrario, en materiales con un porcentaje más elevado de filosilicatos (limos y arcillas) el error puede llegar a los 25". Este hecho no tiene repercusión en la interpretación de las polaridades magnéticas, pero si en las reconstmcciones palinspásticas y paleogeográficas basadas en los cálculos de paleolatitudes a partir de las paleoinclinaciones. Los resultados obtenidos demuestran la necesidad de cautela en la propuesta de conclusiones basadas exclusivamente en este tipo de información., [EN] Alluvial red-beds of two Oligocene succesions in the Southeastem Ebro Basin (Southem Pyrenean foreland, NE Spain) show inclination shallowing, taking into account the reference Oligocene palaeolatitude expected for this region. This fact is interpreted to reflect an inclination error due to either these factors: hydrodynamic control of magnetic particles in the depositional environment, differential compaction of sediment during burial and tectonic deformation. The studied lithofacies are split into five groups: gray sandstones, red sandstones, red siltstones, red mudstones and limestones. A strong positive correlation between the relative amount of phyllosilicates and the magnitude of the inclination error has been established. Lithofacies with low percentage of phyllosilicates (limestones and gray sandstones) display a statistically not significant error of 5" with respect to the magnetic palaeofield inclination, whereas the sediments with a higher phyllosilicate content (siltstones and mudstones) show significant errors of up to 25". This observation has not a major consequence for the interpretation of the magnetic polarity but is crucial for palaeogeographic and palinspastic reconstmctions based on palaeolatitudinal data. The obtained results in this study highlight that the interpretation of paleolatitude based on paleomagnetic data is sometimes not straightfonvard and it requires a detailed evaluation of the rock magnetic parameters (AMS in particular) to reveal the presence of such inclination deflection., Los autores expresan su agradecimiento a M. Inglés por los datos aportados sobre la mineralogía de las lutitas y a M. Steiner por la identificación de minerales magnéticos al microscopio y por las facilidades dadas en su laboratorio durante la estancia del primero de los firmantes. Igualmente agradecen los comentarios aportados por M. Garcés y R. Molina que han contribuido a mejorar este trabajo, que se encuadra en los proyectos de la CICYT no PB-97-0882-C03-01 y de la DGES no. PB96-0815 del Ministerio de Educación y Cultura. También fue en parte financiado por el "Grup de Recerca de Qualitat SGR 97-73, del Comissionat per Universitats i recerca de la Generalitat de Catalunya (Geodinamica i Analisi de Conques). X. Barbera ha disfrutado de una beca doctoral FPI del Ministerio de Educación y Ciencia y de las ayudas de viaje relacionadas con la misma.

The presence of Dactyloidites ottoi is first recorded in the Eocene Sant Llorenç del Munt fan-delta complex. This constitutes the first citation for the Paleogene. The ichnospecies occurs in the lower part of a prograding fan-delta front sequence, associated to other traces produced by sediment-feeders. This association is substituted in the upper part of the sequence by abundant vertical Ophiomorpha indicating an increase of energetic conditions. The paleoenvironmental setting interpreted for Dactyloidites is consistent with that of previous described occurrences

Two new fossil micromammal localities of Middle Miocene age (Pico del Fraile 2, PF2 and Sancho Abarca 5, SA5) from the Tudela Formation (northeastern Ebro Basin) are described. PF2 contains rodents and insectivores of Aragonian age (local zone Dc). The rodent assemblage from the locality SA5 is very scarce and probably of Middle Aragonian age, like PF2. The micromammal fauna from the locality PF2 is very similar to that from Valdemoros 3B (VA3B) (Calatayud-Daroca Basin), including Microdyromys cf. remmerti, a species until now only described from the Miocene of the Daroca-Villafeliche area. Among the fauna recorded in PF2, a form of Democricetodon is described. The sedimentary record of the Pico del Fraile and Sancho Abarca sections and the mammalian findings extend the stratigraphic and paleontological knowledge of this part of the Ebro Basin, and allow its study in a continuous stratigraphic context.

17 pages, 11 figures, 1 table, Space-for-time substitution is a concept that has been widely applied, but not thoroughly tested, in some fields of geomorphology. The objective of this study is to test whether the concept of space-for-time substitution is valid in reconstructing the evolution of a submarine canyon-channel system in a passive progradational margin. We use multibeam echosounder data and in situ measurements from the south Ebro Margin to analyse the morphology and morphometry of a sequence of submarine valleys ordered in terms of increasing valley thalweg length. The morphological model of submarine valley evolution that we can propose from this analysis is very similar to established models in the literature, which leads us to conclude that time can be substituted by space when reconstructing the evolution of submarine canyon and channel systems in the south Ebro Margin. By extracting morphometric information from the application of the space-for-time substitution model to our data, we identify a series of morphological patterns as a submarine canyon evolves in a passive progradational margin. These include the geometric similarity of canyon planform shape, an increase in canyon draining efficiency and in the influence of flank slope failures, and an evolution towards equilibrium between canyon form and imposed water and sediment load without net erosion or deposition taking place. We also observe that canyon elongation is higher downslope and that the canyon undergoes an early stage of rapid incision similar to the process of >erosion narrowing> reported in terrestrial rivers. We demonstrate that the conclusions of our study are not limited to submarine valleys in the south Ebro Margin but are applicable to other margins around the world. © 2014 Elsevier B.V., This research was supported by Marie Curie Intra-European Fellowship PIEF-GA-2009-252702, Marie Curie Career Integration Grant PCIG13-GA-2013-618149 and HERMIONE (grant agreement 226354) within the 7th European Community Framework Programme, DOS MARES (CTM2007-66316-C02-01/MAR), GRACCIE-CONSOLIDER (CSD2007-00067), CASCADES (CTM2008-01334-E) and COSTEM (CTM2009-07806) projects. [...] AM, MC, GL and XT belong to CRG on Marine Geosciences, supported by grant 2009 SGR 1305, Generalitat de Catalunya

Analysis of stratigraphic terminology and classification, shows that time-related stratigraphic units, which by definition have a global extent, are the concern of international cornrnissions and committees of the intemational Union of Geological Sciences (IUGS) . In contrast, lithostratigraphic, and other closely related units, are regional in extent and are catalogued in the International Stratigraphic Lexicon (ISL), the last volume of which, was published in 1987. Tlie intemational Commission on Stratigraphy (ICS) is currently attempting to revitalize the publication of ISL, given that the information contained in published volumes has never been updated, and that there has been a significant increase in stratigraphic research in recent decades. The proliferation of named units in the South Pyrenean and Ebro Basin Paleogene is evaluated to illustrate the extent of the problem. Moreover, new approaches to stratigraphic analysis have led to the naming of genetic units according to similar guidelines followed in the naming of descnptive or lithostratigraphic units. This has led to considerable confusion. The proposal to revitalize the ISL is accepted as part of the solution, that should also include the publication of critica1 catalogues, and the creation of norms for genetic unit terminology.