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Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

The Late Jurassic-Early Cretaceous Cameros Basin comprises an expanded Tithonian to Early Albian stratigraphic record, mainly made up of fluvial and lacustrine systems, but also containing minor marine incursions. This basin is renowned because of preserving numerous ichnites sites, being the Berriasian Oncala Group one of the units that includes more of them. A sedimentological study of the deposits at the Serrantes site demonstrates that the ichnites are clearly associated with tidally-influenced fluvial-deltaic meandering channel and overbank deposits. The facies appearing in this outcrop are: 1) channelized beds, 2) lutites, 3) tabular sandstone beds, 4) black limestones, 5) laminated limestones with gypsum pseudomorphs. The ichnites are clearly associated to the siliciclastic deposits, especially to the lutitic facies, and are absent in the carbonate-evaporitic deposits., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Microbial mats represented the earliest complex ecosystems on Earth, since fossil mineralized examples (i.e., microbialites) date back to the Archean Eon. Some microbialites contain putative remains of organic matter (OM), however the processes and pathways that lead to the preservation of OM within microbialite minerals are still poorly understood. Here, a multidisciplinary study is presented (including petrographic, mineralogical and organic geochemical analyses), focusing on a modern calcifying mat from a hypersaline lake in the Kiritimati atoll (Central Pacific). The results show that this mat has a complex history, with two main growth phases under hypersaline conditions, separated by an interruption caused by desiccation and/or freshening of the lake. The mineral precipitates of the mat are predominantly aragonitic and two contrasting precipitation modes are observed: the main growth phases of the mat were characterized by the slow formation of irregular micritic particles with micropeloidal textures and subspherical particles, linked to the degradation of the exopolymer (EPS) matrix of the mat; whereas the interruption period was characterized by the rapid development of a thin but laterally continuous crust composed of superposed fibrous aragonite botryoids that entombed their contemporaneous benthic microbial community. These two precipitation modes triggered different preservation pathways for the OM of the mat as the thin crust shows a particular lipid biomarker signature, different from that of other layers and the relatively rapid precipitation of the crust protecting the underlying lipids from degradation, causing them to show a preservation equivalent to that of a modern active microbial community, despite them being >1100 years old. Equivalent thin mineral crusts occur in other microbialite examples and, thus, this study highlights them as excellent targets for the search of well-preserved biomarker signatures in fossil microbialites. Nevertheless, t, German Research Foundation, Science and Technology Development Fund, Macau SAR, Ministry of Science and Technology, National Key Research and Development Program, China, Alexander von Humboldt Foundation, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Deciphering the palaeoenvironmental and palaeoclimatic setting of ancient successions that include deposits typical of different climates can be challenging. This is the case in the Late Jurassic succession cropping out in eastern Spain (South-Iberian and western Maestrazgo basins), where deposits characteristic of both arid to semiarid and humid to subhumid settings have been identified through a detailed analysis of eight stratigraphic sections. These sections comprise shallow marine carbonates changing upward and laterally to a predominantly siliciclastic coastal and alluvial succession, including abundant dinosaur remains. Deposition of coastal and alluvial sediments occurred in flood plains, ephemeral and perennial fluvial channels, aeolian dunes, deltas, distributary mouth-bars and associated distributary channels, and shallow water bodies influenced by both fresh and marine waters. Some of these deposits, notably those of aeolian and ephemeral fluvial origin, are characteristic of arid to semiarid climates. However, there are also abundant deposits that can be demonstrably shown to have a coeval origin, which are indicative of permanent water courses: (i) sediments of seasonal discharge fluvial channels with perennial to semi-perennial flow, displaying subcritical and supercritical flow sedimentary structures; (ii) deltaic sediments deposited in permanent freshwater bodies; and (iii) abundant plant and dinosaur remains, especially of herbivorous dinosaurs, which required the presence of permanent water sources and abundant vegetation. These apparently contrasting sedimentary features indicate that deposition occurred under a seasonal climate controlled by monsoonal-type precipitation. These deposits are analogous to those observed nowadays in the Lençóis Maranhenses National Park (north-east Brazil), where a subhumid tropical climate with a seasonal precipitation pattern prevails. Thus, this study shows that only through careful facies analysis and interpreta, Ministerio de Ciencia e Innovación (MICINN), Ministerio de Economía y Competitividad (MINECO), Gobierno de Aragón/FEDER, Universidad Complutense de Madrid, Unidad de Paleontología de Dinosaurios de Teruel, Instituto Aragonés de Fomento, Dinópolis, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Tras la situación sanitaria del curso 2019-2020 y a través del Proyecto INNOVA Gestión 223 de la convocatoria del año 2020-2021, la Facultad de Ciencias Geológicas ha adquirido una herramienta para la virtualización de afloramientos geológicos. Durante el curso 2020-2021 se ha virtualizado una salida de campo de cada uno de los grados que se imparten en la Facultad, Grado en Geología y Grado en Ingeniería Geológica. Además, la mayor parte de la actividad de campo de este curso tendrá lugar durante el mes de mayo, por lo que los profesores van a poder realizar la virtualización de sus salidas de campo mientras realizan la salida presencial con los estudiantes, o incluso en algunas asignaturas los propios estudiantes van a ser los responsables de la virtualización de las mismas. Por ello, la herramienta GIGAPAN no sólo es de elevada utilidad en momentos en los que las restricciones de movilidad impiden la realización del campo sino que también permiten aplicar metodologías docentes invertidas durante la realización de los campamentos. De este modo los estudiantes pasan a tener un papel activo en relación a su proceso de aprendizaje. La herramienta GIGAPAN permite que se combinen imágenes fotográficas de megapíxeles de alta resolución para crear imágenes panorámicas de gigapíxeles que luego se pueden explorar a muchas escalas haciendo zoom y visión panorámica. Los GigaPans son gigapíxeles panorámicos, imágenes digitales con billones de píxeles. Gigapan crea panorámicas enormes, para conseguir elevado detalle con mucha nitidez. Además de proporcionar una experiencia de aprendizaje alternativa, estos recursos permiten una visita 'virtual' que puede ser una herramienta de aprendizaje útil en cualquier escenario docente. La utilidad del material generado tiene validez más allá de la pandemia, ya que puede ser utilizado por los estudiantes en el estudio de las asignaturas de la titulación, con un enorme potencial didáctico hasta ahora poco explorado. Hasta la fecha el GIGAP

Fossils within early Cambrian phosphorites worldwide are often well preserved due to early diagenetic permineralization. Here, we examine the fossil record contained within phosphorites of the Lower Cambrian Pusa Formation (late Fortunian to Cambrian Stage 2) in Fontanarejo, central Spain. The sedimentology and age of these phosphorites have been controversial and are here reviewed and discussed, providing also an updated geological map. The Pusa Formation is composed of fine clastic sediments that are partly turbiditic, with channels of quartz-rich conglomerates and abundant phosphorites in the upper part of the succession. The microfacies and mineralogy of these channel deposits are studied here for the first time in detail, showing that they are mainly composed of subspherical apatite clasts, with minor mudstone intraclasts, quartzite and mica grains. Numerous sponge spicules, as well as entirely preserved hexactinellid sponges and demosponges, were collected within these phosphorites and likely represent stem groups. In addition to sponges, other fossils, such as small shelly fossils (SSF) of the mollusc Anabarella sp., were found. The phosphorites exhibit multiple evidence of intense microbial activity, including diverse fabrics (phosphatic oncoidal-like microbialites, thrombolites, stromatolites and cements) and abundant fossils of filamentous microbes that strongly resemble extant sulphur-oxidizing bacteria. Our findings strongly suggest that microbial processes mediated the rapid formation of most of the Fontanarejo apatite, probably accounting for the exceptional preservation of fragile fossils such as sponge skeletons. The apparent presence of taxonomically diverse hexactinellid and demosponge communities at the lowermost Cambrian further corroborates a Precambrian origin of the phylum Porifera., Alexander von Humboldt Foundation, Göttingen Academy of Sciences and Humanities, University of Göttingen, National Natural Science Foundation of China, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Bioturbation has long been considered an antagonist of microbialite development and preservation, because metazoan grazing and burrowing destroy benthic microbial communities. However, metazoan bioturbation, in conjunction with microbial accretion, may have had a significant role in the morphogenesis of some columnar microbialites, as suggested by the case study presented and by some Phanerozoic and Upper Proterozoic analogues discussed here. Late Miocene in age, the studied microbial biostrome developed in a western Mediterranean restricted shallow-water platform dominated by grainy sediments and with a notable influence of bioturbation. This study is focused on the complex accretionary history of the columnar microbialite biostrome and on its striking dark grey colour, which is attributed to Mn-oxyhydroxides precipitated during meteoric diagenesis linked to subaerial exposure. The characteristic columnar structure of the microbialite biostrome has features consistent with an accretionary origin of the columns, but also has features suggesting metazoan disruption. Therefore, a new morphogenetic model for columnar microbialites is presented, highlighting the concomitant roles of microbial accretion, bioturbation and grainy sediment infill of the intercolumn space. Whether this model is an exception or a rule, should be tested on other examples of Phanerozoic and Upper Proterozoic columnar microbialites. Nevertheless, this model is a step forward in understanding the complex microbe–metazoan interactions as constructive coexistence rather than just as destructive competition., Ministerio de Ciencia e Innovación (MICINN), Gobierno de Aragón/FEDER, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

CRUE-CSIC (Acuerdos Transformativos 2021), Ooids (subspherical particles with a laminated cortex growing around a nucleus) are ubiquitous in the geological record since the Archean and have been widely studied for more than two centuries. However, various questions about them remain open, particularly about the role of microbial communities and organic matter in their formation and development. Although ooids typically occur rolling around in agitated waters, here, we describe for the first time aragonite ooids forming statically within microbial mats from hypersaline ponds of Kiritimati (Kiribati, central Pacific). Subspherical particles had been previously observed in these mats and classified as spherulites, but these particles grow around autochthonous micritic nuclei, and many of them have laminated cortices, with alternating radial fibrous laminae and micritic laminae. Thus, they are compatible with the definition of the term ‘ooid’ and are in fact very similar to many modern and fossil examples. Kiritimati ooids are more abundant and developed in some ponds and in some particular layers of the microbial mats, which leads to the discussion and interpretation of their formation processes as product of mat evolution, through a combination of organic and environmental factors. Radial fibrous laminae are formed during periods of increased supersaturation, either by metabolic or environmental processes. Micritic laminae are formed in closer association with the mat exopolymer (EPS) matrix, probably during periods of lower supersaturation and/or stronger EPS degradation. Therefore, this study represents a step forward in the understanding of ooid development as influenced by microbial communities, providing a useful analogue for explaining similar fossil ooids., Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

Microbial buildups that predate the Messinian salinity crisis, including one of the few Phanerozoic examples of ‘giant’ microbialites, crop out upon the island of Mallorca (W Mediterranean). Sedimentological and geochemical data from microbialites and associated deposits, both essentially dolomitic, indicate that they grew in shallow marine conditions but relatively restricted from the open marine realm. Two microbialite-bearing sequences occur, both consisting of subtidal to supratidal deposits. Periods of restriction led to evaporative and hypersaline conditions that favored the development of microbialites and local precipitation of sulfates. By contrast, ephemeral periods marked by more open conditions were devoid of microbialites and allowed production of bioclastic deposits. Microbialites range from decameter- to decimeter-scale, reflecting differences in accommodation space. Despite contrasting sizes, all microbialite bodies record similar mesostructure evolution through time, from thrombolites to stromatolites, with a sharp transition between these endmembers. The change from subtidal to shallower, more restricted and saline intertidal environments triggered biotic substitution of thrombolite-generating microbial communities to stromatolite-generating ones. Furthermore, a wide variety of microstructures, from agglutinated to micritic with fossilized microbes, indicates that two main accretion processes occurred: microbially-influenced primary dolomite precipitation and grain trapping and binding, which were controlled by the interaction between microbes and changes in environmental conditions (e.g. grain supply, hydrodynamics and hydrochemistry). Therefore, the diversity of macro-, meso- and microstructures of these microbialites was caused by a complex interplay between depositional, biotic and hydrological parameters, which offers useful insights for the palaeoecological interpretation of other examples, at any scale and throughout geological time., Ministerio de Ciencia e Innovación (MICINN), Gobierno de Aragón/FEDER, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

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, Ministerio de Economía y Competitividad (MINECO), Universidad Complutense de Madrid, Geosciences Institute (IGEO-CSIC)., Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

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, En este trabajo se realiza por primera vez un estudio multidisciplinar (estratigráfico, paleontológico, paleoambiental y paleogeográfico) del registro sedimentario del este de España que contiene abundantes fósiles de dinosaurio (DSR) y que tradicionalmente se ha asignado al Jurásico Superior-Cretácico Inferior. En concreto se han estudiado en detalle varias áreas de la Cuenca Suribérica y del oeste de la Cuenca del Maestrazgo en las que los fósiles de dinosaurio son más abundantes. En todas las áreas que se han estudiado, el DSR está formado por una parte inferior (CLP), esencialmente carbonática, y por una parte superior (SUP), esencialmente siliciclástica, que se depositaron en una plataforma carbonática somera o muy somera, que estaba conectada lateralmente, hacia el norte y oeste, con ambientes costeros y aluviales. La evolución de estos sistemas a lo largo del tiempo fue, en general, regresiva, aunque se ha podido registrar en ambas cuencas un episodio transgresivo en la parte más alta del registro estudiado. Respecto a la edad, el DSR se ha asignado previamente a edades comprendidas entre el Kimmeridgiense y el Barremiense (o incluso localmente al Aptiense-Albiense). Sin embargo, las edades obtenidas en este trabajo a partir de macroforaminíferos bentónicos (LBF) demuestran que el DSR tiene una edad Kimmeridgiense–Titoniense y, localmente, Kimmeridgiense–Berriasiense Inferior?. Estos nuevos hallazgos tienen implicaciones importantes en cuanto a la edad de los fósiles de dinosaurio que contienen los depósitos estudiados, que tradicionalmente se han asignado, erróneamente, al tránsito Jurásico-Cretácico o incluso al Cretácico Inferior, y hacen necesaria la realización de una revisión litoestratigráfica y cronoestratigráfica de las unidades previamente establecidas, y definidas, en las áreas de estudio: los nuevos datos indican que el DSR es equivalente a los depósitos de la Formación Villar del Arzobispo, por lo que se debe evitar el uso de las Formaciones Alde, Ministerio de Economía y Competitividad (MINECO), Universidad Complutense de Madrid, Gobierno de Aragón, Instituto Aragonés de Fomento, Ministerio de Educación, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

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

[EN] This study presents new mapping and stratigraphic data from the Villel area (Teruel). In this area, some mesozoic and cainozoic units are identified, described and dated for the first time, including some of the Upper JurassicLower Cretaceous. In addition, the detailed study of the Villar del Arzobispo Fm deposits, which are rich in dinosaur fossils in neighbouring areas, shows that this unit is better recorded in the study area than previously thought and that it was deposited in coastal and shallow marine environments., [ES] Este trabajo presenta nuevos datos cartográficos y estratigráficos del área de Villel (Teruel) y en él se identifican, describen y datan por primera vez unidades de edad mesozoica y cenozoica, incluyendo algunas del Jurásico Superior-Cretácico Inferior. Además, el estudio detallado de los depósitos de la Fm. Villar del Arzobispo, ricos en fósiles de dinosaurios en zonas cercanas, muestra que esta unidad ocupa un área mayor que la descrita previamente en el área de estudio y que se depositó en medios costeros y marinos someros

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

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

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., 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., Ministerio de Economía y Competitividad (MINECO), Universidad Complutense de Madrid, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

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?, 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., Ministerio de Economía y Competitividad (MINECO), Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

[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

[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.