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A series of Pleistocene marine terraces comprised of conglomerate and coarse-grained sandstone aligned NNW-SSE along the Cadiz coast have been recognized and interpreted as formed in very coarse-grained beaches in our work (González-Acebrón et al., 2016). They unconformable overlie either Pliocene units or older Pleistocene deposits. In these terraces, five sedimentary sequences were described and dated by Sr isotopic analysis of well-preserved oysters. This dating provided an Early Pleistocene age (1.3 Ma) for the oldest marine terrace, which corresponds to Sequence 1. Aguirre (2018) does not agree with the dating of the first sequence. Instead, in Aguirre (1995) and Aguirre et al. (1995) these deposits are considered as laterally equivalent to lacustrine deposits located more than 50 km far away (Mesas de Asta, Jerez Basin), and their age (Late Pliocene-lowermost Early Pleistocene) extrapolated to Sequence 1. This is an impossible correlation given the fact that the studied deposits (Sequences 1 to 5) are marine terraces without lateral continuity inland. Finally, Aguirre's (2018) sedimentological interpretation of the deposits of Sequence 1 as part of a “wave- and tide-dominated delta” breaks down when one considers that this delta would be a mixture of non-coeval deposits (the continental deposits of Mesas de Asta together with Sequence 1 deposits).

The Villar del Arzobispo Formation, cropping out in the western Peñagolosa sub-basin (Late Jurassic, eastern Spain), includes abundant dinosaur tracksites and bones, which occur in diverse mixed siliciclastic and carbonate facies deposited from shallow marine to coastal and alluvial paleoenvironments. The lower part of the unit, mainly composed of bioclastic and oolitic limestone, was deposited in an inner carbonate platform, which underwent episodic subaerial exposure and siliciclastic inputs from the emergent areas, and includes scarce dinosaur tracks. This environment evolved into a siliciclastic coastal and alluvial plain that was crossed by channels and affected by periodic flooding events, producing the deposition of splay lobes. Upward, the siliciclastic coastal and alluvial deposits are interbedded with inter- to supratidal limestone beds. These tidal and coastal deposits show the highest abundance, diversity and best preservation of dinosaur tracks and bones of the unit. This setting gradually evolved upward into an inner carbonate platform, producing the deposition of shallow marine bioclastic and oolitic limestone, which includes very scarce dinosaur tracks. The highest abundance, diversity and best preservation of theropod, sauropod, thyreophoran and ornithopod tracks occur at the top of tidal carbonate beds. Tracks also occur in the siliciclastic coastal and alluvial plain deposits, especially in the flood plain deposits, preserved, mainly, as infillings or natural casts. Additionally, very scarce and poorly-preserved tracks occur at the top of shallow marine carbonate beds. Bones may be articulated and/or associated in the flood plain deposits, whereas they are isolated and dispersed in the splay lobe deposits. Although this unit has been previously assigned to the Tithonian-Berriasian, the analysis of larger benthic foraminifera suggests a Kimmeridgian-Tithonian age for the Villar del Arzobispo Formation. This is consistent with the dinosaur assemblag

The Mesozoic Cameros Basin, northern Spain, was inverted during the Cenozoic Alpine orogeny when the Tithonian – Upper Cretaceous sedimentary fill was uplifted and partially eroded. Tar sandstones outcropping in the southern part of the basin and pyrobitumen particles trapped in potential source rocks suggest that hydrocarbons have been generated in the basin and subsequently migrated. However, no economic accumulations of oil or gas have yet been found. This study reconstructs the evolution of possible petroleum systems in the basin from initial extension through to the inversion phase, and is based on structural, stratigraphic and sedimentological data integrated with petrographic and geochemical observations. Petroleum systems modelling was used to investigate the timing of source rock maturation and hydrocarbon generation, and to reconstruct possible hydrocarbon migration pathways and accumulations. In the northern part of the basin, modelling results indicate that the generation of hydrocarbons began in the Early Berriasian and reached a peak in the Late Barremian – Early Albian. The absence of traps during peak generation prevented the formation of significant hydrocarbon accumulations. Some accumulations formed after the deposition of post‐extensional units (Late Cretaceous in age) which acted as seals. However, during subsequent inversion, these reservoir units were uplifted and eroded. In the southern sector of the basin, hydrocarbon generation did not begin until the Late Cretaceous due to the lower rates of subsidence and burial, and migration and accumulation may have taken place until the initial phases of inversion. Sandstones impregnated with bitumen (tar sandstones) observed at the present day in the crests of surface anticlines in the south of the basin are interpreted to represent the relics of these palaeo‐accumulations. Despite a number of uncertainties which are inherent to modelling the petroleum systems evolution of an inverted and overmature

The early stages of intraplate extensional systems commonly are recorded by deposition of continental sediments. In this context, given appropriate tectonics and eustasy, transgressions can be well recorded in the areas of the basins located close to the sea, but they may be difficult to recognize in the innermost landwards areas of the system. This situation occurs in the innermost Upper Jurassic-Early Cretaceous Cameros Basin, part of the Iberian Extensional System (N. Spain), where a Berriasian transgression is recorded. The Berriasian succession in this area consists of siliciclastic deposits (sandstone and mudstone) of the Salcedal Formation and of carbonate and mixed carbonate-fine siliciclastic deposits (limestone and marl) of the San Marcos Formation. The sedimentological analysis of this depositional succession indicates that a Berriasian carbonate coastal wetland system occupied that sector of the Cameros Basin during deposition of the San Marcos Formation. This carbonate coastal wetland system consisted of shallow and quiet water bodies including some with marine influence others with no to very little marine influence, and palustrine areas. A semiarid climate characterized by the seasonal alternation of short wet and long dry periods caused water bodies of the system to undergo episodic desiccation and subaerial exposure. Moreover, this complex mosaic of sub-environments was connected laterally with a distal zone of a distributive fluvial system that was rimmed by siliciclastic tidal flats during phases of greater marine influence. The paleogeographic arrangement of this coastal wetland depositional system indicates that the marine influence came from the Basque-Cantabrian Basin to the north. During the period of Berriasian maximum marine influence, accommodation linked to the eustatic rise added to accommodation generated by tectonic subsidence from the extensional reactivation of late Variscan strike-slip faults. All these factors favored marine incurs

An integrated stratigraphic, palaeontological, palaeoenvironmental and palaeogeographical study of the traditionally considered Upper Jurassic–Lower Cretaceous dinosaur-bearing sedimentary record (DSR) of eastern Spain is accomplished for the first time. Several areas where dinosaur fossils are abundant (western Maestrazgo and South-Iberian basins) have been studied in detail. In all the areas, the DSR comprises a carbonate-dominated lower part (CLP), and an essentially siliciclastic upper part (SUP). Deposition occurred in a shallow-very shallow marine carbonate platform, laterally connected towards the N and W to coastal and alluvial environments. The overall upwards evolution is regressive with a transgresive episode at the uppermost part. The DSR includes deposits previously assigned, depending on the studied area, from the Kimmeridgian to the Barremian (locally even to the Aptian–Albian). However, ages obtained in this work from larger benthic foraminifera (LBF), demonstrate a Kimmeridgian–Tithonian age (locally Kimmeridgian-Early Berriasian?) for the DSR. These findings have important implications regarding the age of dinosaur fossils of these deposits, traditionally assigned to the Jurassic-Cretaceous transition, or even to the Early Cretaceous, erroneously, and have necessitated a deep litho- and chronostratigraphic revision of the units previously established in the studied areas: new data indicate that the DSR is correlatable with deposits of the Villar del Arzobispo Fm and that the usage of the Aldea de Cortés and El Collado Fms, traditionally assigned to the Early Cretaceous, should be avoided. New data also reveal that the DSR should be correlated with other Kimmeridgian–Tithonian dinosaur-bearing deposits of Iberia, such as those of the Cameros Basin, Asturias and Portugal, and have encouraged a revision of the Iberian palaeogeography at that time. In fact, ages obtained from LBF agree with data provided by the systematics of dinosaurs, since dinosaur

Trapping and binding of allochthonous grains by benthic microbial communities has been considered a fundamental process of microbialite accretion since its discovery in popular shallow-marine modern examples (Bahamas and Shark Bay). However, agglutinated textures are rare in fossil microbialites and, thus, the role of trapping and binding has been debated in the last four decades. Recently, renewed attention on this subject has produced new findings of fossil agglutinated microbialites (those mainly formed by ‘trapping and binding’ and analogous to modern examples), but they are still few and geologically recent (mainly post-Paleozoic) when compared to the 3.5 Gyr long record of microbialites. In order to better understand this discrepancy between modern and fossil examples, an extensive literature review is presented here, providing the first thorough database of agglutinated microbialites, which shows that all of them are formed in shallow-marine environments and most under tidal influence. In addition, a Lower Cretaceous example is described, including very diverse microbialites, each of them formed in a particular paleoenvironment. Some of these microbialites developed in grainy settings, but only those formed in marginal-marine tide-influenced environments accreted mainly by trapping and binding the surrounding grains, being analogous of modern agglutinated microbialites, and matching the environmental pattern observed in the literature database. The combination of the literature review with the case study allows to discuss the factors that control and enhance ‘trapping and binding’: a) occurrence of grains in the microbialite environment; b) frequent currents that mobilize the grains and supply them onto the microbialite surface; c) high concentration and diversity of electrolytes in the water to increase the adhesiveness of the extracellular polymeric substances (EPS) of the microbialite surface; and d) a CaCO3 saturation state not high enough to promote earl

The Villar del Arzobispo Formation is a mixed siliciclastic-carbonate unit that crops out at eastern Spain and has been traditionally assigned to the Late Tithonian–Middle Berriasian. In the Maestrazgo and South-Iberian Basins, this unit, which includes abundant dinosaur remains, was deposited in an inner platform that evolved upwards into a coastal and alluvial plain, and finally into an inner platform again (CAMPOS-SOTO et al., 2016a; 2016b). The detailed micropaleontological study of this unit has shown the presence of a larger foraminifera association dominated by Alveosepta personata in its lower part, indicating a Kimmeridgian age for the lower part of the unit (CAMPOS-SOTO et al., 2016a). The upper part of the unit contains a larger foraminifera association dominated by Anchispirocyclina lusitanica, indicating a Tithonian–earliest Berriasian? age for the uppermost part (CAMPOSSOTO et al., 2016b). A Late Jurassic age for the Villar del Arzobispo Fm is, in fact, consistent with the dinosaur fossils preserved in the unit, which show a Late Jurassic affinity (COBOS et al., 2014). The Jurassic-Cretaceous boundary has been recently formally changed by the Berriasian Working Group and it has been placed in the middle of Chron M19n, at the base of Calpionellid Zone B (delimited by the Crassicollaria to Calpionella turnover) in deep shelf to pelagic marine deposits (OGG et al., 2016). This change will have implications when dating coastal and continental deposits, which typically contain very scarce fossils with chronostratigraphic value. This is the case of the Villar del Arzobispo Fm, which contains dinosaur fossils currently considered as typical of the Late Jurassic (COBOS et al., 2014; CAMPOS-SOTO et al., 2016b).

The Upper Jurassic Villar del Arzobispo Fm is a mixed siliciclastic-carbonate succession that crops out in the Riodeva area (Teruel, eastern Spain) and preserves abundant dinosaur fossils. In this area, the succession has been interpreted as representing the preserved accumulation of an inner carbonate platform that evolved upwards into a predominantly siliciclastic fluvial system with minor marine carbonate incursions. However, preliminary studies performed in this area have revealed the presence of aeolian deposits intercalated with tidal, scarce alluvial and marine deposits, suggesting deposition in a coastal plain setting, rather than a fluvial system. In this work, we analyse the aeolian deposits of the Villar del Arzobispo Fm to reconstruct the depositional environments of the unit. For the first time, we describe the occurrence of dome-shaped aeolian dunes in the Mesozoic record of Iberia. The studied deposits are arranged in metre-thick sandstone beds (up to 10 m). Beds exhibit flat bases and tops, and a lateral continuity up to 300 m and occur interbedded with edaphized, reddish siliciclastic mudstone. Two facies associations are distinguished. The Aeolian dune facies association consists on fine-to medium-grained, well-to very well-sorted sandstone, which displays different types of large-scale cross-bedding. (1) Tangential cross-bedding is arranged in up to 2 m-thick sets, displaying tangential foresets (angles of 20-35°) and reactivation surfaces; internally, it is formed by mm-to cm-thick laminae that pinch out upwards and downwards. (2) Low-angle cross-bedding is arranged in sets up to 2.7 m-thick, displaying low-angle foresets (< 15°), laterally extensive bottomsets and reactivation surfaces; internally, it consists of mm-to cm-thick laterally continuous laminae. (3) Dome-shaped cross-bedding is arranged in up to 4 m-thick sets, consisting of convex-up, steeply dipping foresets (up to 35°) with preserved topsets. These features are typical of migratin

Maximum Mesozoic transgressions flooded many continental areas worldwide, forming a wide and shallow seaway on the Iberian Microplate during the Late Cretaceous. Several siliciclastic and mixed siliciclastic–carbonate units developed along the Iberian Massif (cratonic area) while, at the same time, epeiric carbonate platforms spanned Iberia. These siliciclastic deposits unconformably cover the Variscan basement, as well as the Permian and Triassic deposits. This study focuses on sandstone provenance in central Spain, in a transgressive, relatively quiet tectonic setting with a wide rock variety in the potential source areas. Results shown in this paper can be applied in analogue systems; transgressive sandstones often form important hydrocarbon reservoirs due to their high primary porosity. The Cretaceous siliciclastic deposits are included in four formations ranging in age from the Cenomanian to the early Coniacian. The deposits were initially of fluvial origin, followed by a coastal-tidal setting. Quantitative petrographic analysis of sandstones from these formations reveals compositional variations related to provenance and weathering degree. The oldest formation (Utrillas Fm.) was deposited on a paleorelief surface. Sandstone composition changes from arkosic sandstones in the depressed area (Petrofacies P1a) to younger quartzarenites when sediments were deposited on top of the paleotopographic high (Petrofacies P1b). Quartz grains in both sub-petrofacies are angular to subangular, and the framework is poorly sorted. Intense weathering conditions are deduced for Petrofacies P1b, manifested by grain infiltration, clay coatings, and the absence of plagioclase grains and alteration features on K-feldspars. All these observations have been related to wetter conditions during P1b deposition. Main source areas of the Utrillas Fm were Ordovician metasediments and orthogneisses, Permian volcanic rocks, and Triassic Buntsandstein facies. Petrofacies 2 encompasses the thre

The Cameros Basin (North Spain) is a Late Jurassic‐Early Cretaceous extensional basin, which was inverted during the Cenozoic. It underwent a remarkable thermal evolution, as indicated by the record of anomalous high temperatures in its deposits. In this study, the subsidence and thermal history of the basin is reconstructed, using subsidence analysis and 2D thermal modelling. Tectonic subsidence curves provide evidence of the occurrence of two rapid subsidence phases during the syn‐extensional stage. In the first phase (Tithonian‐Early Berriasian), the largest accommodation space was formed in the central sector of the basin, whereas in the second (Early Barremian‐Early Albian), it was formed in the northern sector. These rapid subsidence phases could correspond to relevant tectonic events affecting the Iberian Plate at that time. By distinguishing between the initial and thermal subsidence and defining their relative magnitudes, Royden's (1986) method was used to estimate the heat flow at the end of the extensional stage. A maximum heat flow of 60–65 mW/m2 is estimated, implying only a minor thermal disturbance associated with extension. In contrast with these data, very high vitrinite reflectance, anomalously distributed in some case with respect to the typical depth‐vitrinite reflectance relation, was measured in the central‐northern sector of the basin. Burial and thermal data are used to construct a 2D thermal basin model, to elucidate the role of the processes involved in sediment heating. Calibration of the thermal model with the vitrinite reflectance (%Ro) and fluid inclusion (FI) data indicates that in the central and northern sectors of the basin, an extra heat source, other than a typical rift, is required to explain the observed thermal anomalies. The distribution of the %Ro and FI values in these sectors suggests that the high temperatures and their distribution are related to the circulation of hot fluids. Hot fluids were attributed to the hydrotherma

[CA] Aquest projecte consta de la implementació d’una prova de concepte per a demostrar l’us de les tecnologies Big Data a l’actualitat a l’àmbit de la salut. S’han preparat les diverses part del programa pensant en que siga accessible via web, altament escalable, fiable, i útil per al sistema sanitari actual. En concret es centra amb el framework de Storm, basat en Streaming i al que li se dona utilitat en molts àmbits en l’actualitat; la seua filosofia de Streams encaixa de forma molt adequada amb el problema de les rutes assistencials proposat al títol, i dona moltes possibilitats al tractament d’aquestes de forma rapida i distribuïda.

The Cameros Basin is a paleo-petroleum system formed in the north-eastern Iberian Peninsula. The basin formed during the Mesozoic Iberian Rift and was later inverted during the Alpine orogeny. Hydrothermal events took place during the post-extensional and inversion stages, producing an important impact on the thermal history of the basin. In order to determine the source rock of the petroleum system of the basin, organic matter characteristics, the petroleum generation potential and the maturity of the basin infill are determined by means of petrology and geochemical analyses. Several organic rich units of the stratigraphic record of the basin are potential source rocks for hydrocarbons generation, although their characteristics differ depending on their location. Organic matter content in the northern sector is scarce and limited to vitrinite, inertinite and solid bitumen particles. The residual total organic carbon (TOC < 1%), the low hydrocarbon potential (S2 < 0.3 mg HC/g rock, HI < 50 mg HC/g TOC), the mature to overmature thermal stages (%Ro from 1.7 to 4.6) and the presence of solid bitumen particles indicate that hydrocarbons have been already generated by these rocks. In contrast, the southern sector of the basin is characterized by abundant organic matter remnants (TOC from 2 to 17%) and immature to early oil-window thermal conditions (0.38–0.75%Ro), indicating a high hydrocarbon potential for these rocks (S2 from 11 to 123 mg HC/g and HI values from 23 to 715 mg HC/g TOC). The different evolution of the source rocks in the basin is the result of the combination of differential subsidence rates, which determine different thermal histories and of the circulation of hydrothermal fluids in the northern-central sector during the evolution of the basin.

[ES] Este trabajo aporta nuevos datos cartográficos y sedimentológicos para aclarar la controvertida evolución tectónica extensional de la Cuenca de Cameros (N de España). La geometría actual del borde norte de la cuenca representa la continuación de lineaciones tardivariscas NO-SE y SO-NE reconocidas en la Cuenca Vasco-Cantábrica, a lo largo de las cuales se produjo una importante tectónica salina sin-extensional. En la zona de estudio, la distribución irregular de los depósitos plásticos del Keuper es interpretada aquí como debida a una movilización sin-extensional. De este modo, la estructuración tardivarisca del basamento y las movilizaciones de Keuper, asociadas a ella, permiten explicar la arquitectura y distribución de las unidades sin-extensionales del relleno de la cuenca., [EN] This work provides new mapping and sedimentological data to shed light on the controversial extensionaltectonic evolution of the Cameros Basin (N Spain). The present-day geometry of the northern margin of the basin represents the continuation of NW-SE and SW-NE late-variscan lineaments of the Basque-Cantabrian Basin, along which important syn-extensional salt-tectonics occurred. In the study area, the irregular distribution of the Keuper plastic deposits is interpreted here as due to syn-extensional mobilization. Thus, the late-variscan basement structure and the Keuper mobilizations related to it, allow explaining the architecture and distribution of the syn-extensional units of the basin infill

Exceptional pedogenetic calcretes occur in the earliest syn-rift sedimentary record (Tithonian) of the west Cameros Basin. These calcretes show different types of pedogenetic facies (nodular, massive, laminar, and brecciated–pisolithic) and microfabrics: brecciated intraclasts, carbonate nodules, coated clasts and grains, etched quartz grains, rhizocretions, pedotubules and fragmented alveolar–septal structures. In addition, calcrete fragments have been observed in the conglomerate and sandy channelized deposits that form the alluvial systems, indicating the reworking of previous calcrete deposits. Calcrete facies appear organized in several sequences developed over different architectural elements in three different types of alluvial systems. The type of calcrete sequence is different depending on the architectural arrangement of each alluvial-fan system. Laminar (L (MN)–S) and brecciated–pisolithic (BP (L)–S) calcrete sequences are predominant in the alluvial sedimentary record of poorly channelized alluvial systems. These calcretes are thick, morphologically complex, and laterally continuous, due to the formation of long-term stable subaerial surfaces favored by the intermittent behavior of the alluvial systems. Massive-nodular (M (N)–S) and laminar (L (MN)–S) sequences are predominant in highly channelized alluvial systems and develop only locally in interchannel or floodplain areas where sedimentation stops temporally. Calcrete sequences in the distributive fluvial fan systems can be considered as poorly developed, being massive-nodular (M (N)–S) and nodular (N–S). After analyzing the location of these calcrete sequences in the studied record and their genesis and environmental significance, their variations can be related to different autocyclic factors such as sedimentation rate, channel network organization, texture of the host sediment, and water-table influence. Also three main allocyclic factors such as climate, tectonics, and drainage area controlled the

The studied Pleistocene deposits at the Cadiz coast are located on the current intertidal zone or at cliffs parallel to the actual coast (6.50 m a.s.l.) from the localities of El Puerto de Santa María to Chiclana. Five sequences of very coarse-grained beaches have been recognized and dated. They unconformably overlie Pliocene units and are formed by clast-supported conglomerate and coarse-grained sandstone. Chronological ages (87Sr/86Sr and AMS 14C analysis) and stratigraphic correlation stand that the oldest marine terrace is the one placed topographically higher and towards the SE of Cadiz city, dated as Early Pleistocene (1.3 Ma). After it, the sea retreatment produces subaerial exposure of Sequence 1 and the development of several calcrete profiles and a paleokarst. Subsequent sea-level rises allow the sedimentation of Sequences 2, 3 and 4 during Early-Middle Pleistocene (1 to 0.8 Ma) in areas close to Cadiz city, with subaerial exposure recorded at the top of Sequences 3 and 4. During the very Upper Pleistocene, sedimentation of Sequence 5 occurs towards the SE of Cadiz city. Based on the spatial position of Sequence 5 we can conclude that this area constituted a downthrown block during the Latest Pleistocene, in relation to neotectonic processes and diapirism. Sandstone framework (hybrid arenites) reveals that main source areas for these marine terraces include units from the Betic Orogene (Betic external zones -Triassic and Jurassic rocks-and the Gibraltar arc), the Guadalquivir basin passive margin (Iberian Massif), the Guadalquivir foreland basin (marine Miocene and Pliocene record) and local inputs of Pleistocene units. The siliciclastic supplies from sources were mainly constant during the sedimentation of all set of sequences, suggesting maturation processes as reworking and recycling of homogenized sediments during transport. Early diagenetic processes have been identified as carbonate cementation, neomorphism and dissolution, outlining the deduced sea

[EN] The study of the Upper Jurassic-Lower Cretaceous deposits (Higueruelas, Villar del Arzobispo and Aldea de Cortés Formations) of the South Iberian Basin (NW Valencia, Spain) reveals new stratigraphic and sedimentological data, which have significant implications on the stratigraphic framework, depositional environments and age of these units. Moreover, these new data encourage revising the previously proposed stratigraphic correlations between the studied units and those deposited in adjacent areas of the Iberian Basin. The Higueruelas Fm was deposited in a mid-inner carbonate platform where oncolitic bars migrated by the action of storms and where oncoid production progressively decreased towards the uppermost part of the unit. The overlying Villar del Arzobispo Fm has been traditionally interpreted as an inner platform-lagoon evolving into a tidal-flat. Here it is interpreted as an inner-carbonate platform affected by storms, where oolitic shoals protected a lagoon, which had siliciclastic inputs from the continent. The Aldea de Cortés Fm has been previously interpreted as a lagoon surrounded by tidal-flats and fluvial-deltaic plains. Here it is reinterpreted as a coastal wetland where siliciclastic muddy deposits interacted with shallow fresh to marine water bodies, aeolian dunes and continental siliciclastic inputs. The contact between the Higueruelas and Villar del Arzobispo Fms, classically defined as gradual, is interpreted here as gradual and rapid, because the transition between both units comprises few meters. More importantly, the contact between the Villar del Arzobispo and Aldea de Cortés Fms, previously considered as unconformable, is here interpreted as gradual. The presence of Alveosepta in the Villar del Arzobispo Fm suggests that at least part of this unit is Kimmeridgian, unlike the previously assigned Late Tithonian-Middle Berriasian age. Consequently, the underlying Higueruelas Fm, previously considered Tithonian, should not be younger than, [ES] El estudio de los depósitos del Jurásico Superior-Cretácico Inferior (formaciones Higueruelas, Villar del Arzobispo y Aldea de Cortés) de la Cuenca Suribérica (NO provincia de Valencia, E España) ha revelado nuevos datos estratigráficos y sedimentológicos, que tienen implicaciones importantes sobre el marco estratigráfico, el ambiente sedimentario y la edad de estas unidades. Además, estos nuevos datos sugieren que se deberían revisar las correlaciones estratigráficas realizadas previamente entre las unidades estudiadas y aquéllas depositadas en otras áreas adyacentes de la Cuenca Ibérica. La Fm Higueruelas se depositó en la parte media de una plataforma carbonática en la que migraban barras oncolíticas por la acción de las tormentas y en la que la producción de oncolitos disminuía progresivamente hacia la parte alta de la unidad. La Fm Villar del Arzobispo suprayacente ha sido interpretada tradicionalmente como una plataforma interna-lagoon que evolucionó a una llanura mareal. En este trabajo se reinterpreta como una plataforma carbonática interna afectada por las tormentas y en la que se desarrollaban bajíos oolíticos que protegían un lagoon. Esta plataforma también estaba afectada por la llegada de material siliciclástico del continente. La Fm Aldea de Cortés ha sido interpretada previamente como formada en un lagoon bordeado por llanuras mareales y por llanuras deltaicas fluviales. En este trabajo se reinterpreta como depositada en un humedal costero en el que interaccionaban depósitos lutíticos, cuerpos de agua someros de salinidades dulces a marinas, dunas eólicas y descargas continentales de material siliciclástico. El contacto entre las Formaciones Higueruelas y Villar del Arzobispo, definido clásicamente como gradual, es interpretado en este estudio como gradual y rápido, ya que la transición entre ambas unidades ocupa muy pocos metros. De forma más importante, el contacto entre las Formaciones Villar del Arzobispo y Aldea de Cortés, considerado previa

[ES] Este trabajo aporta nuevos datos cartográficos y sedimentológicos para aclarar la controvertida evolución tectónica extensional de la Cuenca de Cameros (N de España). La geometría actual del borde norte de la cuenca representa la continuación de lineaciones tardivariscas NO-SE y SO-NE reconocidas en la Cuenca Vasco-Cantábrica, a lo largo de las cuales se produjo una importante tectónica salina sin-extensional. En la zona de estudio, la distribución irregular de los depósitos plásticos del Keuper es interpretada aquí como debida a una movilización sin-extensional. De este modo, la estructuración tardivarisca del basamento y las movilizaciones de Keuper, asociadas a ella, permiten explicar la arquitectura y distribución de las unidades sin-extensionales del relleno de la cuenca., [EN] This work provides new mapping and sedimentological data to shed light on the controversial extensionaltectonic evolution of the Cameros Basin (N Spain). The present-day geometry of the northern margin of the basin represents the continuation of NW-SE and SW-NE late-variscan lineaments of the Basque-Cantabrian Basin, along which important syn-extensional salt-tectonics occurred. In the study area, the irregular distribution of the Keuper plastic deposits is interpreted here as due to syn-extensional mobilization. Thus, the late-variscan basement structure and the Keuper mobilizations related to it, allow explaining the architecture and distribution of the syn-extensional units of the basin infill.

[ES] La Fm. Villar del Arzobispo es una unidad mixta siliciclástico-carbonática que es considerada como la unidad que representa la culminación de la tendencia regresiva del Jurásico terminal-Cretácico basal en la parte suroriental de la Cuenca Ibérica. En el oeste de la sub-cuenca de Penyagolosa (Cuenca del Maestrazgo) esta unidad está formada, en su parte inferior, por una alternancia de carbonatos marinos, areniscas y lutitas y, en la parte media y superior, por lutitas y areniscas, principalmente, que alternan con calizas que se van haciendo progresivamente más abundantes hacia el techo de la unidad. Estas calizas son peloidales, bioclásticas y oolíticas y contienen abundantes fósiles marinos. La presencia de estas facies marinas demuestra la existencia de un periodo transgresivo durante la sedimentación de la parte superior de la unidad. El estudio micropaleontológico ha revelado la presencia de una asociación de foraminíferos dominada por Anchispirocyclina lusitanica y del alga dasycladal Zergabriella embergeri, que indican que el episodio transgresivo tuvo lugar durante el intervalo Titoniense superior-¿Berriasiense inferior?, [EN] The Villar del Arzobispo Fm is a mixed siliciclastic-carbonate unit, which is considered as the unit that represents the culmination of the Late Jurassic-basal Cretaceous regressive trend in the southeastern Iberian Basin. In the western Penyagolosa sub-basin (Maestrazgo Basin) this unit is formed, in its lower part, by an alternation of marine limestone, sandstone and siliciclastic mudstone and, in the middle and upper part, by siliciclastic mudstone and sandstone alternating with limestone, which is progressively more abundant towards the uppermost part of the unit. This limestone is formed by peloids, bioclasts and ooids and contains abundant marine fossils. The presence of these marine facies demonstrates that a transgression took place during the sedimentation of the upper part of the unit. The micropaleontological study reveals the presence of a foraminifera association dominated by Anchispirocyclina lusitanica and the dasyclad algae Zergabriella embergeri, indicating that the transgressive episode took place during the Upper Tithonian-Lower Berriasian? interval.

Alluvial systems are sensitive sedimentary systems that can preserve useful information about tectonics, drainage area (lithology and size), and climate. However, research on this subject over the last three decades has made it evident that the interaction of these three factors and their control over the alluvial architecture and facies are complex. The stratigraphic and sedimentological analysis of the earliest syn-rift sedimentary record (Tithonian) in the West Cameros Basin has confirmed that sedimentation during the beginning of extension in this area took place in a series of halfgraben basins in which three different types of fan-shaped alluvial systems were deposited: two relatively large systems, specifically, a “highly channelized alluvial fan system” and a “distributive fluvial fan system changing downstream to an axial tributary fluvial system,” were the exception; and small “poorly channelized alluvial fan systems” were the norm. A semiarid climate is inferred during this earliest syn-rift sedimentary record from the steady and extensive calcrete development. This semiarid climate should play an important role both in how coarser sediment discharges to the rift halfgraben basins occurred and in the dominant transverse organization of the alluvial depositional systems. However, the climate and source-area lithology can be considered steady factors, so the main factors considered as the cause of these sedimentary and architectural heterogeneities are the tectonics and drainage-area sizes, and specifically, the different behavior of each extensional structure in terms of the rate of tectonic uplift and subsidence. This indicates how fault activity and drainage-area sizes during the earliest stages of a rift system can generate high degrees of heterogeneity in the architecture of alluvial basins and how this heterogeneity is recorded by the alluvial systems in the form of differences in their facies association and architecture. Therefore, this work conclud

The Iberian Chain is a Cenozoic intraplate thrust belt located within the Iberian plate. Unlike other belts in the Iberia Peninsula, the scarcity of geophysical studies in this area results in a number of unknowns about its crustal structure. The Iberian Chain crust was investigated by means of a NE-SW refraction/wide-angle reflection seismic transect and two magnetotelluric profiles across the chain, oriented along the same direction. The seismic profile was designed to sample the crust by means of three shots designed to obtain a reversed profile. The resulting velocity-depth model shows a moderate thickening of the crust toward the central part of the profile, where crustal thickness reaches values above 40. km, thinning toward de SW Tajo and NE Ebro foreland basins. The crustal thickening is concentrated in the upper crust. The seismic results are in overall agreement with regional trends of Bouguer gravity anomaly and the main features of the seismic model were reproduced by gravity modeling. The magnetotelluric data consist of 39 sites grouped into two profiles, with periods ranging from 0.01 s to 1000 s. Dimensionality analyses show significant 3D effects in the resistivity structure and therefore we carried out a joint 3D inversion of the full impedance tensor and magnetic transfer functions. The Mesozoic and Cenozoic basins along the Chain are well characterized by shallow high conductive zones and low velocities. Elongated conductors reaching mid-crustal depths evidence the presence of major faults dominating the crustal structure. The results from the interpretation of these complementary geophysical data sets provided the first images of the crustal structure of the Iberian Chain. They are consistent with a Cenozoic shortening responsible of the upper crust thickening as well as of the uplift of the Iberian Chain and the generation of its present day topography.

[EN] The intraplate Cameros rift basin in the north of Spain was formed came into being between the Tithonian and the Early Albian and contains 9 000 m of mostly continental sediments. This basin is a good example of cyclicity of different depositional sequences (DSs) in sedimentary environments, which show clear repetition in their sandstone composition (petrofacies) and diagenetic patterns. The DSs are arranged in two megasequences (MSs) separated by a tectonic unconformity. A similar vertical sandstone compositional evolution, subdivided into two stages that repeat cyclically, has been recognised in both MSs: the first comprises quartzo-sedimentolithic petrofacies and the second is made up of several quartzo-feldspathic petrofacies. This was caused by a progression from the recycling of the pre-rift sedimentary cover to the erosion of the mainly plutonic and metamorphic crystalline basement. These changes in the erosion of the different source areas were conditioned by the tectonics of the basin. Furthermore, the original sandstone framework composition conditioned the diagenetic pattern of the two stages: quartzo-sedimentolithic sandstones containing large amounts of very pervasive carbonate cement that reduce their original porosity considerably, and quartzo-feldspathic petrofacies with a rigid framework that maintained the original pores during burial diagenesis. This compositional and diagenetic pattern is probably applicable to other non-volcanic rifted basins, depending upon the original amount of carbonate rock fragments present., [ES] La cuenca intraplaca de rift de Cameros se localiza al norte de España. Se desarrolló entre el Titónico y el Albiense Inferior, depositándose 9000 m de sedimentos fundamentalmente continentales. La cuenca es un buen ejemplo de ciclicidad en los medios sedimentarios en las diferentes Secuencias Deposicionales (SD), lo que genera una clara repetición de la composición de las areniscas (petrofacies) y de las pautas diagenéticas. Las SD están organizadas en dos megasecuencias (MS) separadas por una discordancia de carácter tectónico. Ambas MS presentan una evolución vertical similar en la composición de las areniscas, generando una repetición de dos estadios: (1º) constituido por una petrofacies cuarzosedimentolítica y (2º) formado por varias petrofacies cuarzofeldespáticas. Este hecho viene motivado por el cambio desde la erosión de una cobertera sedimentaria pre-rift a la erosión del basamento cristalino, principalmente constituido por áreas fuente plutónicas y metamórficas. Estos cambios en la erosión de distintas áreas fuente están controlados por la tectónica de la cuenca. Además, la composición original del esqueleto de las areniscas condiciona el tipo de diagénesis para los dos estadios anteriormente descritos: las areniscas cuarzosedimentolíticas contienen abundante cemento de carbonato, que reduce su porosidad inicial drásticamente. Sin embargo, las areniscas cuarzofeldespáticas presentan un esqueleto más rígido que mantiene los poros originales durante la diagénesis de enterramiento. Este patrón composicional y diagenético es probablemente aplicable a otras cuencas de rift intraplaca no volcánicas, dependiendo de la cantidad inicial de fragmentos de roca carbonática.

[EN] A detailed sedimentological study of the first synrift continental deposits recorded in the Bijuesca Halfgraben (Bijuesca and Ciria Formations), has allowed to understand the stratigraphic architecture of the sediments which record the beginning of the extension in this structure. The Bijuesca Fm consists of detrital sediments arranged in three different alluvial fan (i.e., proximal, medium and distal) facies associations. This unit is made up by two retrograding sequences that consist of siliciclastics and carbonate detrital deposits eroded from the Jurassic prerift units. These sequences record sedimentation in an alluvial fan system with low-efficiency of transport. The Ciria Fm consists of lacustrine carbonate sediments arranged in shallowing-upwards sequences. The predominance of pedogenic modifications affecting the lacustrine sediments and the absence of deep lacustrine facies, allow classifying this lake system as a low-gradient ramp margin lake with low energy. The characteristics of both depositional systems agree with the tectonic situation supposed for the early stages of a rift system., [ES] Un estudio sedimentológico detallado de los primeros depósitos continentales sinrift que aparecen en el Semigraben de Bijuesca (Formaciones Ciria y Bijuesca), ha permitido entender la arquitectura estratigráfica de los sedimentos que representan el principio de la extensión en esta estructura. La Fm Bijuesca está formada por sedimentos detríticos organizados en tres asociaciones de facies diferentes (de abanico aluvial proximal, medio y distal). La unidad está constituida por dos secuencias retrogradantes formadas por sedimentos siliciclásticos y carbonáticos procedentes de la erosión del Jurásico marino prerift. Las dos secuencias representan la sedimentación en un sistema aluvial de baja eficacia de transporte. La Fm Ciria está formada por sedimentos carbonáticos lacustres organizados en secuencias elementales de somerización. El predominio de las modificaciones pedogenéticas que afectan a estos sedimentos y la ausencia de facies lacustres profundas permiten clasificar el sistema lacustre como uno con margen de tipo rampa con bajo gradiente y baja energía. Las características de los dos sistemas deposiconales concuerdan con la situación tectónica de los estadios tempranos de un sistema de rift.

[EN] Fluvial-fan and fluvial siliciclastic strata, developed during the rifting that generated the Cameros Basin (North Spain), record important provenance changes that reveal source areas compositions and locations, paleodrainage evolution and rift patterns. The Tera Group represents the first rifting stage in the Cameros Basin, containing fluvial-fan sediments at the lower part of the sedimentary fill that evolve to fluvial and lacustrine systems in the upper part of the record. Our quantitative sandstone petrographic analysis evidences the presence of three main petrofacies related closely to the rift basin evolution. At the base of the sedimentary succession, Petrofacies 1 (quartzolithic) indicates that the fluvial-fans source areas included Jurassic marine carbonates and older siliciclastic Mesozoic units, as well as metamorphic supplies from the West Asturian Leonese Zone (WALZ).Variscan basement sources of this metamorphic area (WALZ) were more abundant in the upper fluvial record (Petrofacies 2, quartzofeldspathic). Further, the influence of plutonic source areas with a mixed potassic and calcium-sodium composition is also recorded, probably related to the Central Iberian Zone (CIZ). In addition, a local sedimentary input was active during the fluvial riftand lacustrine stages (Petrofacies 2 and 3, both quartzofeldspathic), as a function of the palaeogeographical position of the Jurassic marine rocks and the level of erosion reached. Plutonic rock fragments have not been observed in the Tera Group sandstones of the western part of the basin. Thus, deeper erosion of the basement in the eastern Cameros Basin is suggested. The provenance evolution from quartzolithic to quartzofeldspathic petrofacies registered in Tera Group siliciclastic deposits is due to the higher influence of transversal supplies during the fluvial-fan stage (quartzolithic) to more important axial inputs during the fluvial stage (quartzofeldspathic). This provenance change represents the ev, [ES] Los sedimentos de abanicos fluviales y fluviales propiamente dichos desarrollados durante el proceso de rift que generó la Cuenca de Cameros (Norte de España) registraron importantes cambios de procedencia que proporcionan información sobre la composición y localización de sus áreas fuente, la evolución del paleodrenaje y los patrones de rift. Este estudio se centra en el Grupo Tera (Tithoniense) en el sector oriental de la Cuenca de Cameros. El Grupo Tera representa el primer estadio de rift en dicha cuenca, y está constituido por sedimentos de abanicos fluviales en la parte inferior del relleno sedimentario, que evolucionan a sistemas fluviales y lacustres hacia la parte superior del registro. El estudio petrográfico cuantitativo de las areniscas indica la presencia de tres petrofacies principales que muestran una estrecha relación con la evolución del rift. En la base del registro sedimentario, la Petrofacies 1 (cuarzolítica) manifiesta que las áreas fuente de los abanicos fluviales incluyen tanto carbonatos Jurásicos marinos como unidades siliciclásticas mesozoicas previas, así como influencias metamórficas de la Zona Asturoccidental Leonesa (WALZ). Los aportes del basamento varisco procedentes de esta área fuente metamórfica (WALZ) fueron más importantes en la parte alta del registro (Petrofacies 2, cuarzofeldespática). Además, se detecta la influencia de áreas fuente plutónicas con una composición mixta (potásica y calcosódica), probablemente relacionadas con la Zona Centroibérica (CIZ). También existió un aporte sedimentario local durante los estadios fluviales y lacustres (Petrofacies 2 y 3, ambas cuarzofeldespáticas), que tuvo lugar en función de la posición paleogeográfica de las rocas marinas Jurásicas y del nivel de erosión alcanzado. Si comparamos los dos sectores de la cuenca, los fragmentos de roca plutónica no han sido observados en las areniscas del Grupo Tera en el sector occidental de la cuenca. Por lo tanto, se deduce un nivel de erosión del

[EN] During the most active rifting stages in the northwestern sector of the Iberian Basin (Cameros Basin and Aragonese Branch of the Iberian Range), thick sequences of continental clastic deposits were generated. Sandstone records from Rift cycle 1 (Permo-Triassic) and Rift cycle 2 (Late Jurassic-Early Cretaceous) show similarities in composition. Based on the most recent data, this paper describes sandstone petrofacies developed during both rifting periods. Six petrofacies can be distinguished: two associated with Rift cycle 1 (PT-1 and PT-2) and four with Rift cycle 2 (JC-1 to JC-4). All six petrofacies can be classifi ed as sedimentoclastic or plutoniclastic. Sedimentoclastic petrofacies developed during early rifting stages either through the recycling of pre-rift sediments or signifi - cant palaeogeographical changes. These facies comprise a thin succession (<100 m) of clastic deposits with mature quartzose and quartzolithic sandstones containing sedimentary and metasedimentary rock fragments. Carbonate diagenesis is more common than clay mineral diagenesis. Sedimentoclastic petrofacies have been identifi ed in Rift cycle 1 (Saxonian facies, PT-1) and Rift cycle 2 (JC-1 and JC-3; Tithonian and Valanginian, respectively). In the absence of the pre-rift sedimentary cover, metasedimentoclastic petrofacies sometimes develop as a product of the erosion of the low- to medium-grade metamorphic substratum (Petrofacies JC-2, Tithonian-Berriasian). Plutoniclastic petrofacies were generated during periods of high tectonic activity and accompanied by substantial denudation and the erosion of plutonites. Forming thick stratigraphic successions (1000 to 4000 m), these feldspar-rich petrofacies show a rigid framework and clay mineral diagenesis. In Rift cycle 1, plutoniclastic petrofacies (PT-2) are associated with the Buntsandstein. This type of petrofacies also developed in Rift cycle 2 in the Cameros Basin (JC-4) from DS-5 to DS-8 (Hauterivian-Early Albian), and represent, [ES] Durante las fases de rifting más activas en el sector noroccidental de la Cuenca Ibérica (Cuenca de Cameros y Rama Aragonesa de la Cordillera Ibérica), se generaron potentes sucesiones detríticas de depósitos continentales. Los registros arenosos del ciclo Rift 1 (Permo-Triásico) y Rift-2 (Jurásico Superior-Cretácico Inferior) muestran similitudes en cuanto a su composición. El presente trabajo describe las petrofacies arenosas desarrolladas durante los dos períodos de rifting. Es posible establecer un total de seis petrofacies: dos relacionadas con el Rift-1 (PT-1 y PT-2) y cuatro con el Rift-2 (JC-1 a JC-4). Todas estas petrofacies pueden ser consideradas bien como sedimentoclásticas o como plutoniclásticas. Las petrofacies sedimentoclásticas se desarrollaron durante las etapas iniciales de rifting debido al reciclado del registro sedimentario pre-rift, o por importantes cambios paleogeográfi cos. Aparecen constituyendo sucesiones de depósitos clásticos poco potentes (<100 m) con areniscas cuarzosas y cuarzolíticas maduras con fragmentos de roca sedimentaria y metasedimentaria. La diagénesis está dominada por la presencia de carbonatos sobre los minerales de la arcilla. Esta petrofacies ha sido reconocida durante el ciclo Rift-1 (PT-1, facies saxoniense) y Rift-2 (JC-1 y JC-3; Titoniense y Valanginiense, respectivamente). Además, puede desarrollarse una petrofacies metasedimentoclástica debido a la erosión del sustrato metamórfi co de bajo y medio grado, una vez desmantelada la cobertera sedimentaria pre-rift. Las petrofacies plutoniclásticas se desarrollaron durante los periodos de máxima actividad tectónica asociada a un importante proceso de denudación y erosión de rocas plutónicas en el área fuente. Constituyen registros estratigráfi cos potentes (1000 a 4000 m) con petrofacies arenosas feldespáticas caracterizadas por un esqueleto rígido y el predominio de una diagénesis protagonizada por los minerales de la arcilla. Durante el ciclo Rift-1, la petrofaci