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The reconstruction of the geometry of igneous bodies in inverted basins is often a difficult task, because most of their volume can be either below or above the topographic surface. Indirect methods, such as the determination of their internal fabric can give clues to constrain geometrical reconstructions. The Sant Salvador intrusion, located in the Late Carboniferous-Permian Cadí basin (Central-Eastern Pyrenees), is a good example for testing the application of magnetic fabrics to shallow igneous bodies because of (i) its characteristics in terms of crystal composition/orientation, showing a homogeneous petrofabric controlled by plagioclase crystals 0.4 mm in size, (ii) its good, though partial, preservation, (iii) its position in the stratigraphical succession, between volcaniclastic sediments and unconformably overlying red beds, and (iv) the many unknown factors related to the intrusion, including the geometry of the body and its depth and the amount of erosion after intrusion. Furthermore, the Sant Salvador intrusion provides opportunity for checking the correspondence between the petrofabric and the magnetic fabrics when the magnetic carriers of susceptibility (with an average value of 5217·10 SI) are mainly ferromagnetic. In this case the main magnetic carriers are magnetite and also hematite, the latter resulting from oxidation processes at the paleosurface. The results of Anisotropy of Magnetic Susceptibility show a bimodality in the K disposition after bedding restitution: vertical in the deeper areas of the intrusion and subhorizontal, E-W, in the uppermost stratigraphic positions with an intermediate necking zone in which transition from vertical to horizontal flow is interpreted to occur. Bands deflecting the mineral foliation at the micro scale have also a tectonic or thermal origin but do not seem to interfere with the magnetic ellipsoid axes. Columnar jointing is interpreted to be parallel to the long axis of the intrusion (and therefore to magma flo

This article is composed of three independent commentaries about the state of Integrated, Coordinated, Open, Networked (ICON) principles (Goldman et al., 2021, https://doi.org/10.1002/essoar.10508554.1) in the Geomagnetism, Paleomagnetism, and Electromagnetism (GPE) section and discussion on the opportunities and challenges of adopting them. Each commentary focuses on a different topic: Global collaboration, reproducibility, data sharing and infrastructure; Inclusive equitable, and accessible science: Involvement, challenges, and support of early career, BIPOC, women, LGBTQIA+, and/or disabled researchers; Community engagement, citizen science, education, and stakeholder involvement. Data sharing practices and open repository use still varies strongly between GPE communities. Some have a long tradition of data sharing; others are only starting it. Globally, GPE leadership is strongly dominated by white males and diversity may increase through the creation of Science Equality Commissions. Improved global stakeholder involvement can increase research impacts and help fight inequalities. In all investigated topics we see promising beginnings but also recognize obstacles that include a lack of funding, a lack of understanding of diversity, and prioritizing short-term gain over long-term benefit. Nonetheless, we are hopeful that our community will embrace ICON science

The aim of this work is the application of the anisotropy of magnetic susceptibility (AMS) to the study of volcanic materials from the Late Carboniferous-Permian Cadí basin (southern Pyrenees) in order to (i) explore the limits of this technique in ancient volcanic materials that have undergone strong chemical alteration and a complex tectonic evolution and (ii) provide new insights on the deposition of volcanic materials in this tectonically controlled sedimentary basin. To establish a comparison with the petrofabric of rocks, AMS was complemented with observations and orientation analyses at the outcrop scale, in oriented polished blocks and in thin sections under the microscope. High resolution sampling (620 specimens from 56 sites located in five transects along a sequence 150 m thick) allowed to characterize the volcaniclastic and lava flow series. The AMS results show a fairly constant average magnetic lineation oriented WNW-ESE (in situ and tilt-corrected) and two secondary maxima (N-S to NE-SW in some areas). The magnetic mineralogy analyses indicate the contribution of paramagnetic and ferromagnetic (magnetite, Tc 580 °C) phases to susceptibility. The magnetic fabric has a close relationship with the spatial distribution and orientation of the mineral and grain components of the studied rocks, mainly controlled by depositional processes, with a negligible contribution of the tectonic imprint. Therefore, the magnetic lineation (i.e. K1 axes) can be reliably used as a paleoflow indicator. Nevertheless, it was not possible to establish a clear correspondence between lithological and magnetic fabric types. The results obtained indicate that the AMS approach represents a powerful tool to infer the paleoflow pattern in ancient volcanic and volcaniclastic rocks, even under a priori unfavourable conditions.

[EN] This work integrates geological, geophysical and petrophysical data in order to study residual Bouguer anomalies localized in the Central Pyrenean Axial Zone (between the Noguera-Ribagorzana and Segre rivers to the West and East, respectively). The study area is characterized by thrust sheets of basement Paleozoic rocks forming an antiformal stack and southwards vergence due to the Alpine orogeny, high structural complexity related to the Variscan and Alpine deformation and scarce subsurface data. The Paleozoic rocks present a high variability both in lithology and age. The geological data are based on published geological cartographies and new acquired data, the gravimetric data consist of previous and new data acquired during the 2018 and 2019 (reaching a total of 3590 gravity stations) and the petrophysical data correspond to 526 density measurements. The Bouguer anomaly map of the study area shows a longwave relative minimum (~40 km) with several relative maxima and minima of short- and medium wave (between 2 and 20 km). The residual anomaly map, which allows to investigate the gravimetric anomalies that originated in the upper crust, shows a complex pattern of maxima and minima that does not follow the N110E Pyrenean main direction. Six NNESSO geological cross sections were gravimetrically modeled. The observed gravity response along the cross sections varies according to lithological and rheological changes in the upper crustal rocks, presence of evaporitic rocks both at surface and subsurface, presence of Upper Carboniferous granites, Ordovician gneisses and Neogene rocks belonging to the Cerdanya basin and rocks with different metamorphic grade. Our results also allow to delineate the lateral continuity of structures. This work highlights, in absence of other more resolute geophysical data, the high potential and applicability of gravity data acquired in structurally complex areas when combining with geological and petrophysical data in order to constra

Prehistoric combustion structures are a consequence of the economic and social conditions of past communities. Through the study of the “social life” of a combustion structure of the SBUS (simple basin structure with unconstrained stones) type, which are abundant in the archaeological record of the Iberan northeast, specifically in the Barcelona Plain, this paper will explore the degree of implantation and consolidation of neolithic societies in their surrounding territory. Thanks to the close collaboration between rescue archaeologists and university specialists, a systematic collection of high-resolution analytical techniques was carried out for the combustion structure (EC2) located at Carrer Aurora (Raval archaeological site, Barcelona). Our deployed toolset includes geological, archaeomagnetic, archaeobotanical, microspatial, micromorphological and biochemical analyses. This is the first time this type of approach has been applied to a combustion structure from the northeastern coast of the Iberian Peninsula to better understand their process of construction, use and abandonment.

The Middle Eocene Climate Optimum (MECO) was a 0.5 Myr warming interval that punctuated the long-term cooling trend of the middle to late Eocene. It has been identified worldwide by a gradual negative shift of the dO18 followed by a sharp return to the cooling trend. The peak warming at about 40 Ma coincides in some records with a sharp negative excursion of the d13C, which suggested a relation of the warming event with a transient increase of pCO2. Results from various records also point to increased seasonality and chemical weathering of the source area in coincidence with the MECO. The interval of the MECO is stratigraphically well constrained in the south-central Pyrenees, from the Graus-Trempto the Aínsa and Jaca basins thanks to previous biostratigraphic and magnetostratigraphic investigations. During this period, the south-Pyrenean foreland formed a narrow and shallow elongated basin connected to the west to the Atlantic Ocean. Here we present a record of the MECO in the carbonate platform succession (the Santo Domingo Member of the Arguis Fm.), that accumulated on the Iberian foreland margin, currently outcropping along the External Sierras (the frontal thrust sheet of the southern Pyrenees). Polished samples were micro-drilled to analyse the d18O and d13C isotopes ratios separately from the mud fraction and shells of different species of larger benthic foraminifera. The results show trends of the d18O from the mud fraction that parallel the global ocean isotope signature but with values that are offset towards more negative values (-4¿). There, the influence of the continental waters in the isotopic signal was possibly amplified by the restricted marine paleogeographic context. Results from fossil shells gave values significantly different from the mud fraction: d18O from Nummulites shells were consistently offset towards more positive values compared to mud, which could indicate a different fractionation pathway or, alternatively, a preferred diagenetic al

Past sedimentary archives provide invaluable comparative insights to understand Earth¿s surface reaction to climate shifts and perturbations. Foreland basins are particularly interesting settings for investigating the sedimentary record of ancient climate perturbations because their high-accommodation and high-sedimentation rates favour protracted and expanded records that complement more distal oceanic records. In addition, due to their proximity to source areas, they provide direct information on the land surface response to the regional impacts of global climate shifts. However, besides climate signals, the stratigraphic record of foreland basins is subject to a broad range of other factors that make its interpretation challenging. Indeed, foreland basins are naturally sensitive to the influence of tectonics on sediment production and accommodation, either associated with the long-term tectonic evolution of the orogen-basin system, or with the more local and regional shorter-term structural dynamics and geodynamic perturbations. Moreover, if connected to oceanic domains, eustatic sea-level oscillations can also combine with the above factors in determining final stratigraphic patterns. Over the last two decades, a large body of paleoclimate work has produced new and crucial data on global climate events that have affected our planet. In particular, a suite of global climate perturbations (warming, cooling) have been identified in the Paleogene, thanks to stable isotope of C and O, with some major global warming events such as the PETM, ETM2&3, the EECO, the MECO and others that have fundamental implications for the current global climate crisis. This well-established climatic template provides a unique opportunity to test the impact of climate on surface systems in deep time, particularly during the Paleogene hothouse. Therefore, we here present our work on the Isabena section in the South Pyrenean Foreland basin, which is a uniquely continuous and well exposed s

We have carried out a detailed paleomagnetic study of volcanic rocks (18 sites) and red beds (10 sites) from the Late-Carboniferous-Permian series of the Cadí Basin (Eastern Pyrenees). The study provides reliable Late Carboniferous-Permian paleomagnetic directions, in an area where paleomagnetic studies are scarce. The main characteristic component in both rock types shows a SSE direction with a shallow inclination and a dominant reverse polarity. The magnetic carriers, both in the volcanic rocks and the red beds, are magnetite and hematite. The main component is interpreted as a primary magnetization of Permian age in the red beds; in the Late Carboniferous volcanic rocks, the main component likely represents primary magnetization or early remagnetization. These results are consistent with the poles for the Iberian plate during the Permian and indicate an absence of regional vertical axis rotations for the Orri nappe, in whose hanging wall the Cadí Basin was transported southwards during the Pyrenean orogeny.

The Padul-15-05 sediment core provides an exceptional perspective of the paleoenvironmental and climate change in the Western Mediterranean region for the last ca. 200 kyr. However, even though a robust chronology mainly relying on radiometric dating is available for the last 50 ka, the chronology for the older sediments is not yet fully resolved. Ages for the bottom part of the core (>21 m) were previously inferred from amino-acid racemization dating and sediment accumulation rates. In this work, we provide a more accurate chronology for the older part (>100 kyr) of the Padul-15-05 sediment core record based on the recognition of past Earth¿s magnetic excursions. We identify an interval prone of reversed polarity samples close to MIS-5e/5 d transition that we correlate to the Blake geomagnetic excursion (116.5 kyr¿112 kyr). In addition, we identify an interval of low inclinations and two reversed samples that we interpret as the Iceland Basin geomagnetic excursion (192.7 kyr¿187.7 kyr: wide scenario of VGP <40¿). Our new results, which include IRM acquisition curves that contribute to understand the magnetic mineralogy, enhances the robustness of the age model for the Padul-15-05 sedimentary sequence by adding an independent age dataset with new accurate tie-points. Our refined age control together with the available paleoenvironmental and paleoclimate multiproxy data provide insightful information to unveil the response of the western Mediterranean environments to regional environmental and climate change.

A recent paper by Gao et al. (2022) has suggested that the mechanisms leading to magnetic enhancement in Iberian Pliocene continental sediments are similar to those affecting the world-known loess sequences in China. Hence, Gao et al. have pointed that formation of nano-sized (superparamagnetic, SP) pedogenic ferrimagnetic grains during periods of increased rainfall drives magnetic enhancement in alluvial sediments from the Teruel basin despite their different depositional setting. Assessing whether this is a common phenomenon is important given the relevance of the Iberian continental record, which spans most of the Cenozoic and might represent a prime source of high-resolution paleoclimate 74 information. Here we provide new paleoenvironmental and rock magnetic results from the Tudela Formation (western Ebro basin), an Early to Middle Miocene sequence largely made up of distal alluvial mudrocks subjected to incipient (alfisol-type), syndepositional pedogenic processes. Frequency-dependent magnetic susceptibility measurements point to two periods of SP magnetic enhancement at around 20.5-20.2 Ma and 18.6-17.2 Ma, broadly coinciding with the presence of dispersed evaporite deposition in the context of a progressive increase in subtropical humid conditions preceding the Miocene Climate Optimum (MCO). Noticeably, magnetic enhancement is low between 17.2-15.5 Ma, coinciding with the peak of the MCO as signaled by sedimentological and paleontological evidence. These results suggest that magnetic enhancement in the studied sediments is neither driven by wet conditions nor by dry ones, but rather by the combination of both at times of increased climate (possibly seasonal) variability, En un artículo reciente, Gao et al. (2022) han sugerido que los mecanismos que condicionan el aumento de la magnetización en sedimentos continentales del Plioceno de la Península Ibérica son similares a los que afectan al mundialmente conocido loess chino. Estos autores han señalado que, a pesar de las diferencias sedimentológicas que se observan entre ambos tipos de materiales, el aumento de la magnetización que afecta a los sedimentos de la Cuenca de Teruel también está condicionado por el mismo proceso que ha afectado al loess: la presencia de partículas ferrimagnéticas de origen pedogénico y tamaño nanométrico (superparamagnéticas, SP) formadas durante períodos de aumento de las precipitaciones. Evaluar si éste es un proceso común en sedimentos aluviales de la Península Ibérica es importante dada la relevancia del registro continental ibérico, que abarca la mayor parte del Cenozoico y podría arrojar importantes datos paleoclimáticos a alta resolución. En este trabajo se presentan nuevos resultados paleoambientales y de magnetismo de rocas de la Formación Tudela, una secuencia de edad Mioceno inferior y medio que aflora en el sector occidental de la Cuenca del Ebro y está compuesta, en su mayor parte, por lutitas aluviales distales sometidas a procesos pedogenéticos incipientes (tipo alfisol). Las medidas de la susceptibilidad magnética a doble frecuencia indican la formación de partículas SP entre hace 20.5-20.2 Ma y 18.6-17.2 Ma, periodos que coinciden con la presencia de niveles y nódulos de yesos formados en el contexto de un aumento progresivo de las condiciones de temperatura y humedad que precedieron al óptimo climático del Mioceno (MCO). Los sedimentos formados entre 17.2 y 15.5 Ma, coincidiendo con el pico del MCO, no presentan cantidades significativas de partículas SP. Esto sugiere que la formación de dichas partículas SP no parece haber respondido tanto a la prevalencia de condiciones húmedas o secas como a la combinación de ambas en momentos de mayor

The Cova del Gegant (Barcelona) is a Paleolithic archaeological site with evidence of human occupation between MIS 5 and MIS 2 (Daura et al. 2021). Its rich fossil record includes a repertoire of Middle and Upper Paleolithic lithic industry, various faunal taxa, remains of Homo neanderthalensis and evidence of pyrotechnology. The latter consists of hearths documented and excavated in the stratigraphic profile preserved at the end of the GP2 gallery. Their dimensions are small (generally no more than 1 m in diameter) and are characterized by facies of white and/or gray calcitic ash over thin underlying dark (black layer) and reddish (rubefacted) facies. Given their limited size and the fact that samples for other techniques have also been collected, it was not possible to collect oriented samples for archaeomagnetic (directional) analysis and the sampling focused on studying the magnetic properties. The main objective is to characterize the magnetic properties of these facies in order to determine the variations in the composition, concentration and granulometry of the ferromagnetic minerals present in the samples, as well as to infer possible heating temperatures. Almost 50 samples from different hearths were analysed, including several control samples of non-thermally altered sediments. The magnetic analyses include the measurement of magnetic susceptibility, stepwise acquisition isothermal remanent magnetization curves, hysteresis loops (+/- 1 T), backfield curves and thermomagnetic curves up to 700 ºC. All samples are dominated by ferrimagnetic minerals (magnetite and/or maghemite), with slight variations of hematite depending on the facies. Unlike the black and reddish subjacent facies, ashes exhibit the highest ferromagnetic mineral concentration and high thermomagnetic reversibility, indicating that they reached the highest heating temperatures (> 500 – 600 ºC). The integration of these results with the previous data from Cova del Gegant and the body of knowle, La Cova del Gegant (Barcelona), es un yacimiento paleolítico con evidencias de ocupación humana entre el MIS 5 y el MIS 2 (Daura et al. 2021). Entre su rico registro fósil destaca un amplio repertorio que incluye industria lítica del Paleolítico Medio y Superior, diversos taxones faunísticos, restos de Homo neanderthalensis y evidencias de pirotecnología. Estas últimas consisten en hogares documentados y excavados en la parte final de la galería GP2, parte de los cuales se conservan en el perfil estratigráfico. Sus dimensiones son reducidas (generalmente no exceden 1 m) y se caracterizan por facies de ceniza calcítica de color blanco y/o gris, sobre finas facies subyacentes de color oscuro (nivel negro) y enrojecido (rubefactadas). Dado sus reducidas dimensiones y que también se han recogido muestras para otras técnicas, no fue posible recoger muestra orientada para análisis arqueomagnéticos y el muestreo se centró en estudiar las propiedades magnéticas. El objetivo principal es caracterizar las propiedades magnéticas de estas facies con el fin de determinar sus variaciones en la composición, concentración y granulometría de los minerales ferromagnéticos presentes, así como inferir posibles temperaturas de calentamiento. Se han analizado unas 50 muestras de diferentes hogares, incluyendo también varias muestras de control de sedimento no termoalterado. Los análisis magnéticos incluyen la medida de la susceptibilidad magnética, curvas de adquisición progresiva de la magnetización remanente isotermal, ciclos de histéresis (+/- 1 T), curvas de backfield y curvas termomagnéticas hasta 700 ºC. Todas las muestras están dominadas por minerales ferrimagnéticos (magnetita y/o maghemita), con ligeras variaciones de hematites según la facies analizada. A diferencia de las facies oscuras y rubefactadas, las cenizas presentan la mayor concentración de minerales ferromagnéticos y una alta reversibilidad termomagnética, indicativas de que alcanzaron las mayores temperaturas (> 500

The record of the Eocene-Oligocene Transition (EOT) in the alluvial-lacustrine successions of the Ebro Basin is reviewed in the light of a refined stratigraphic correlation framework. Earlier works provided a magnetostratigraphic correlation for this time interval that was meant to fit with the available small-mammals biochronology (Costa et al., 2011; Barberà et al., 2001). A key constraint to this study was the Santpedor locality (Agusti et al., 1987; Vianey-Liaud et al., 2019), which yielded a characteristic post-Grande Coupure small mammal assemblage, then attributed to the lowest Oligocene. The extended magnetostratigraphy provided in this work challenges earlier correlations and puts forward an alternate scenario that reveals a severe misfit with the continental biochronology framework based on the fossil mammal record. Or results indicate that the locality of Santpedor, bearing a post-Grande Coupure assemblage is correlated to the late Eocene, with an age 1.5 Myr older than the EOT, thus challenging the view that the Grande-Coupure marks the onset of the Oligocene in the continental realm. The significance of this discrepancy in terms of heterochrony of biostratigraphic events, the punctuated character of faunal replacement across the EOT, and time lags between the marine and continental realms may need to be addressed. The magnetostratigraphic record obtained across the EOT transitions reveals the presence of a short geomagnetic event of normal polarity within chron C13r, and very close to the Eocene-Oligocene boundary (Fig. 1). Despite not being yet reported in the GPTS, this event is recognized in several other records in different geographic locations around the globe, and sedimentary environments (Valero et al., 2015; Tauxe et al., 1984; Katz et al., 2008; Miller et al., 1993). Thus we suggest that it truly represents a global geomagnetic feature that deserves the category of either subchron (C13r.1n) or cryptochron (C13r-1). The results of this work emp, En este trabajo se analiza el registro de la Transición Eoceno-Oligoceno (EOT) en las sucesiones aluviales-lacustres de la cuenca del Ebro, a partir de la revisión de las correlaciones estratigráficas y de nuevos datos magnetoestratigráficos. Trabajos anteriores proporcionaron una correlación para este intervalo de tiempo que perseguía encajar con el marco biocronológico existente (Costa et al., 2011; Barberà et al., 2001). Una información clave fue la localidad de Santpedor (Agusti et al., 1987; Vianey-Liaud et al., 2019), que había aportado una asociación de micromamíferos post-Grande Coupure, evento de renovación de faunas terrestres que clásicamente se ha interpretado como marcador de la base del Oligoceno. Los nuevos registros magnetoestratigráficos proporcionados en este trabajo presentan un escenario alternativo contradictorio con la información biocronológica. Los nuevos resultados indican que la localidad de Santpedor se correlaciona con el Eoceno superior, con una edad 1.5Myr anterior al EOT, desafiando así la visión de la Grande-Coupure como evento que da inicio al Oligoceno en el continente. La importancia de esta discrepancia en términos de heterocronía de eventos bioestratigráficos, el carácter puntuado del reemplazo de la fauna a lo largo del EOT y los desfases de tiempo entre los reinos marino y continental, es un aspecto que merecerá discusión. El registro magnetoestratigráfico de la transición EOT revela la presencia de una breve magnetozona de polaridad normal que se correlaciona con la parte superior del cron C13r, muy próxima del límite Eoceno-Oligoceno, y que no tiene su registro en la escala de tiempo de polaridad geomagnética (Fig. 1). Una magnetozona en una posición equivalente se ha reconocido en registros de diferentes lugares del planeta y ambientes sedimentarios (Valero et al., 2015; Tauxe et al., 1984; Katz et al., 2008; Miller et al., 1993). Por lo tanto, sugerimos que esta magnetozona realmente representa un evento geomagnético global

Magnetic properties have long been used as a non-expensive and relatively fast methodology to identify mineral particles in atmospheric particulate matter (PM). Most anthropogenic activities (burning fossil fuels, industrial procedures involving high temperatures) produce magnetic particles, being magnetite and maghemite the most common (Larrasoaña et al., 2021 and references therein). In the Mediterranean area, North African Dust (NAD) is a substantial component of PM. The presence of larger hematite particles have been identified in more intense events of NAD deposition (Larrasoaña et al., 2021 and references therein). In this work we analyze the rock magnetic properties (IRMs and magnetic susceptibility) of 240 PM samples located in 7 localities from NE Iberia (Pamplona, Orgi, Almudévar, Zaragoza, Ordesa, Chiprana, Montseny) from 2017 to 2021 in collecting periods of 16 to 75 days. The magnetic susceptibility has been measured in three different conditions in KLY3 and MFK2 instruments (AGICO Inc.) (Zaragoza University and GEO3BCN-CSIC laboratories) and the IRM has been measured with a superconducting rock magnetometer (2G Enterprises) after applying a field of 0.3 and 1.2 T with an Impulse Magnetizer IM10-30 (ASC Scientific)at the paleomagnetic laboratory of CCiTUB - GEO3BCN CSIC, Barcelona. In addition, detailed acquisition of IRM was performed in 4 samples. Correlation index (R2) between measurements of magnetic susceptibility are 0.7 and 0.8. HIRM (IRM@1.2 T-IRM@0.3 T) values are larger than 2·10-3 Am2/kg in Chiprana the months of dic-17, oct-21 and nov-21; Montseny in (aug-20,nov-20,dic-20, oct-21, nov-21), Zaragoza in jan and nov-20, oct-21, Orgui (aug-18) and Almudévar (dic-20)., Las propiedades magnéticas se han utilizado como una herramienta barata y relativamente rápida para identificar partículas minerales en materia particulada atmosférica (PM por siglas en inglés). La mayoría de las actividades humanas (quema de combustibles fósiles, procesos industriales a altas temperaturas) producen partículas magnéticas, siendo magnetita y maghemita las más comunes (Larrasoaña et al., 2021 y referencias). En el área del Mediterráneo, el polvo de África del Norte (NAD por siglas en inglés) es un componente importante de la PM. La presencia de hematites de mayor tamaño identifica eventos más intensos de NAD (Larrasoaña et al., 2021 y referencias). En este trabajo se analizan la IRM a 0.3 y a 1.2 T y la susceptibilidad magnética en tres condiciones diferentes en 240 muestras localizadas en 7 sitios del NE peninsular (Pamplona, Orgi, Almudévar, Zaragoza, Ordesa, Chiprana, Montseny) desde 2017 a 2021, en periodos de recogida que varían de 16 a 75 días. La susceptibilidad magnética se ha medido en KLY3 y MFK2 (AGICO Inc.) (Universidad de Zaragoza y GEO3BCN-CSIC) y la IRM se ha medido en un magnetómetro criogénico superconductor (2G enterprises) después de aplicar las IRMs con un magnetizador de pulsos (IM10-30, ASC Scientific) en el laboratorio paleomagnético CCiTUB - GEO3BCN CSIC. Además, la adquisición de la IRM de detalle se ha realizado en 4 muestras. La susceptibilidad magnética presenta índices de correlación (R2) de 0,7 y 0,8 entre las diferentes condiciones de medida. Los valores de HIRM (IRM@1.2 T-IRM@0.3 T) son mayores de 2·10-3 Am2/kg en Chiprana los meses de dic-17, oct y nov-21, Montseny ago/nov/dic-20, oct/nov-21, Zaragoza ene/nov-20, oct-21, Orgui ago-18 y Almudévar dic-20.

[EN] We have carried out a detailed paleomagnetic study of volcanic rocks (18 sites) and red beds (10 sites) from the Late-Carboniferous-Permian series of the Cadí Basin (Eastern Pyrenees). The study provides reliable Late Carboniferous-Permian paleomagnetic directions, in an area where paleomagnetic studies are scarce. The main characteristic component in both rock types shows a SSE direction with a shallow inclination and a dominant reverse polarity. The magnetic carriers, both in the volcanic rocks and the red beds, are magnetite and hematite. The main component is interpreted as a primary magnetization of Permian age in the red beds; in the Late Carboniferous volcanic rocks, the main component likely represents primary magnetization or early remagnetization. These results are consistent with the poles for the Iberian plate during the Permian and indicate an absence of regional vertical axis rotations for the Orri nappe, in whose hanging wall the Cadí Basin was transported southwards during the Pyrenean orogeny.

Stratigraphic cycles preserved in sedimentary successions are controlled by the interaction of tectonics, climate, sediment supply and sea-level variations. Understanding the influence of these drivers on sedimentary systems dynamics is crucial to understand and extract information from sedimentary archives. In the deep marine deposits of the Ainsa foreland basin (lower to middle Eocene, southern central Pyrenees, Spain), the origin of well-preserved cyclicity between channelized sandy submarine fans and hemipelagic deposits remains subject to debate because of the absence of chronostratigraphic constraints on high resolution geochemical proxies. Here, we contrast a combination of newly acquired and legacy geochemical datasets (carbon and oxygen stable isotopes, organic matter content, major and trace elements and the mineralogical composition of bulk hemipelagic sediments) tuned by a new age model to global “target” curves to discuss the possible drivers of the stratigraphic cycles found in the deep marine sediment gravity flow deposits of the Hecho Group. Our new age model is based on magnetostratigraphic and biostratigraphic datasets acquired on a composite section going from the Banaston system to the distal deposits of the Sobrarbe deltaic complex. Four major polarity zones are identified in the studied succession covering the time span from C21n (lower members of the Banaston system) to C19r (Sobrarbe deltaic complex). Our age model is corroborated by the identification of the nannoplankton zone NP16 in the Guaso system (C20n). Comparison between global carbon isotope curve and local isotope dataset shows some differences, suggesting the preservation of a local isotope signal modulated by eustatism, changes in the environment of deposition and/or restriction in water circulation in the Ainsa basin. Yet, comparison of the stratigraphic record with global sea-level curves highlights that sands are mainly delivered to the basin during lowstands, pointing to the i

The propagation of the deformation front in foreland systems is typically accompanied by the incorporation of parts of the basin into wedge-top piggy-back basins, this process is likely producing considerable changes to sedimentation rates (SR). Here we investigate the spatial-temporal evolution of SR for the Tremp–Jaca Basin in the Southern Pyrenees during its evolution from a wedge-top, foreredeep, forebulge configuration to a wedge-top stage. SR were controlled by a series of tectonic structures that influenced subsidence distribution and modified the sediment dispersal patterns. We compare the decompacted SR calculated from 12 magnetostratigraphic sections located throughout the Tremp–Jaca Basin represent the full range of depositional environment and times. While the derived long-term SR range between 9.0 and 84.5 cm/kyr, compiled data at the scale of magnetozones (0.1–2.5 Myr) yield SR that range from 3.0 to 170 cm/kyr. From this analysis, three main types of depocenter are recognized: a regional depocenter in the foredeep depozone; depocenters related to both regional subsidence and salt tectonics in the wedge-top depozone; and a depocenter related to clastic shelf building showing transgressive and regressive trends with graded and non-graded episodes. From the evolution of SR we distinguish two stages. The Lutetian Stage (from 49.1–41.2 Ma) portrays a compartmentalized basin characterized by variable SR in dominantly underfilled accommodation areas. The markedly different advance of the deformation front between the Central and Western Pyrenees resulted in a complex distribution of the foreland depozones during this stage. The Bartonian–Priabonian Stage (41.2–36.9 Ma) represents the integration of the whole basin into the wedge-top, showing a generalized reduction of SR in a mostly overfilled relatively uniform basin. The stacking of basement units in the hinterland during the whole period produced unusually high SR in the wedge-top depozone. © 2020 The Aut

A new gravity survey (1164 gravity stations and 180 samples for density analysis) combined with two new geological cross sections has been carried out in a sector of the Central Pyrenees in order to improve the characterization of basement and cover architecture. From North to South, the study area comprises the southern half of the Axial Zone and the northernmost part of the South-Pyrenean Zone. New gravity data were combined with previous existing databases to obtain the Bouguer and residual anomaly maps of the study area. The two cross sections, oriented NNE–SSW, were built from field data and previous surficial and subsurface data and cross the La Maladeta plutonic complex. The residual anomaly map shows values ranging from −18 to 16 mGal and anomalies mainly oriented N120E. The two 2.5D modelled cross sections show similar observed gravity curves coinciding with similar interpreted structural architecture. Data show a gravity high oriented N120E coinciding with the Orri basement thrust sheet and an important gravity depression, with the same orientation, coinciding with the leading edge at depth of the Rialp basement thrust sheet and interpreted as linked to a large subsurface accumulation of Triassic evaporites. The volume at depth of the La Maladeta and Arties granites has been constrained through gravity modelling. This work highlights that the combination of structural geology and gravity modelling can help to determine the structural architecture of an orogen and localize accumulations of evaporites at depth.

The integration of biostratigraphy, strontium isotope stratigraphy, and magnetostratigraphy allowed for the precise dating of the >3.0-km-thick marine to non-marine foreland sedimentary succession within the Dowlatabad growth syncline along the Frontal Fars arc in the Zagros Fold Belt that extends from eastern Turkey to southern Iran. This area was the missing link to complete the dating of syntectonic deposits in the Fars arc and quantify the migration of sedimentary belts as well as the propagation of folding across the entire Mesopotamian foreland basin. Both are essential for defining the interplay of basin evolution and sequence of folding. Deposition of the foreland marine marls in the Mishan Formation started at ca. 11.5 Ma. The transition to a non-marine basin infill occurred at 4.9 Ma by the progradation of thick fluvial deposits of the Aghajari Formation with a fast accumulation rate of 63 cm/k.y. The beginning of growth strata deposition and thus the onset of folding in the Dowlatabad syncline is dated at 4.65 Ma. The first appearance of carbonate conglomerates sourced from the Guri limestone at 2.8 Ma marked the progressive dismantling of the nearby growing anticlines. The tectonic deformation in the front of the Fars arc was active for at least 2.85 m.y. and ceased at 1.8 Ma before the deposition of the discordant and slightly folded Bakhtyari conglomerates characterized by a clast composition derived from the Zagros hinterland. The compilation of magnetostratigraphic ages reveals that both the migration of the Aghajari-Bakhtyari sedimentary belts and the propagation of the folding front was in-sequence toward the foreland at a rate close to 20 mm/yr in the Fars arc and 15 mm/yr in the Lurestan arc, in the last 20 m.y. These high rates of folding propagation are about one order of magnitude larger than age equivalent shortening rates (∼4 mm/yr in Fars arc and ∼2 mm/yr in Lurestan arc) and thus imply an efficient detachment level at the base of the defor

During the Paleogene and Neogene the NE Iberian plate underwent significant paleogeographic changes driven by the Iberian and European plate collision and the resulting formation of the Pyrenean orogen and its corresponding foreland basin. Shortening resulted in the advance of the orogenic wedge, emplacement of allochthonous units, and progressive basin partitioning. Sediment transfer systems reacted to the evolving paleogeographic scenario, shifting from forebulge to foredeep and wedge-top settings. Critical reorganizations included successive shifts from open to close drainage conditions, which had an strong impact on accommodation, and the stratigraphic architecture of the basin infill, overfill and later erosion. The aim of this work is to synthesize the paleogeographic and sedimentary evolution of the south-pyrenean foreland, with emphasis on the reconstruction of sediment routing, the evaluation of sedimentation rate trends, the timing of sedimentary shifts and the analysis of their causes. Stratigraphic data are compiled in a comprehensive magnetostratigraphybased chronostratigraphic framework. Besides, sedimentary and structural data are put together to produce a series of palinspastically restored paleogeographic maps, which reflect five key stages in the evolution of the region. These stages include: 1) the Late Cretaceous tectonic inversion of the extended Iberian margin; 2) the Early Eocene formation of the southern Pyrenean foredeep; 3) the Middle Eocene widening and overfilling; 4) the late Eocene shift into an internal drainage; and 5) the Late Miocene drainage opening and erosion. In the light of these results, the variable role of tectonics, climate and eustacy at different time scales are discussed.

Syntectonic deposits of the Mesopotamian flexural basin have been dated in the Lurestan and Fars salients in the Zagros foldbelt since the early 2000's but not in the Dezful embayment where most of the Zagros foreland oil is trapped. We use 237 samples collected for magnetostratigraphy to date shallow marine to fluvial-alluvial pre-growth and growth strata deposits along a >2700 m section in the NE flank of the Jarik anticline in north Dezful embayment. The Jarik anticline grew by a combination of compression and coeval diapirism like other structures in north Dezful embayment. The correlation of the local magnetostratigraphy with the Geomagnetic Polarity Time Scale indicates ages of 14.1 Ma and ~13.6 Ma for the bases of the Mishan and Aghajari formations. The bases of Lahbari Mb. and Bakhtyari Fm. are ~9.0 Ma and ~7.0 Ma. The onset of growth strata in the NE flank of the Jarik anticline is ~12.8 Ma with a duration of 5.8 Myr for this anticline. This study presents for the first time the age of syntectonic deposition and folding in the Dezful embayment that is essential to determine burial and generation of hydrocarbons in this oil-rich province. © 2019 Elsevier Ltd

Altres ajuts: CERCA Programme/Generalitat de Catalunya, Els Casots is one of the richest fossil vertebrate sites of the Vallès-Penedès Basin (Catalonia, Spain). It was discovered in 1989 and excavated briefly during the 1990s, resulting in the recovery of thousands of remains and the erection of several new mammal species. Excavations were resumed in 2018 and continue to date. Here we provide updated results regarding the age, stratigraphy, biota and palaeoenvironment of the site. The age of the site is well constrained to ~15.9 Ma thanks to recent bio- and magnetostratigraphic data, thus coinciding with the Miocene Climatic Optimum (MCO). The stratigraphic succession at the site area indicates lacustrine to palustrine environments with cyclically oscillating water level. There are several fossiliferous layers that have yielded a vertebrate fauna comprising up to 75 different vertebrate species including amphibians, reptiles, birds and mostly mammals. The finding of several articulated partial skeletons indicate that the site records an autochthonous to parautochthonous assemblage. The abundance and completeness of the vertebrate remains together with a well-constrained age and detailed stratigraphic and palaeoenvironmental data, make els Casots a key site for understanding wetland ecosystems in southern Europe during the MCO.

The Abocador de Can Mata (ACM) composite stratigraphic sequence (els Hostalets de Pierola, Vallès-Penedès Basin, NE Iberian Peninsula) has yielded a diverse primate assemblage from the late Aragonian (Middle to Late Miocene). Detailed litho-, bio-, and magnetostratigraphic control has enabled an accurate dating of these fossil remains. Comparable data, however, were lacking for the nearby locality of Can Mata 1 (CM1), which yielded a dryopithecine canine of a female individual. Given the lack of hipparionin equids and giraffids, CM1 has been correlated to the latest Aragonian (Mammal Neogene [MN] zone MN7+8). Here we revise the age of CM1 based on fieldwork and associated paleomagnetic samplings undertaken in 2018–2021. Our results extend the ACM composite sequence upward and indicate that CM1 correlates to the earliest Vallesian (MN9). The updated ACM sequence has a thickness of ∼300 m and comprises 12 magnetozones correlated to subchrons C5Ar.1r to C5n.2n (∼12.6–11.1 Ma; latest MN6 to earliest MN9, late Aragonian to earliest Vallesian). CM1 is correlated to C5r.1r (11.146–11.056 Ma), with an interpolated age of 11.11 Ma, thus postdating the dispersal of hipparionin horses into the Vallès-Penedès Basin—which is correlated to the previous subchron C5r.1n, with an interpolated age of 11.18 Ma, and by definition marks the beginning of the Vallesian. CM1 also minimally postdates the earliest record of giraffids at ACM—representing their earliest well-dated occurrence in the basin—being correlated to C5r.1n with an interpolated age of 11.11 Ma. We conclude that CM1 has an earliest Vallesian (MN9) age of ∼11.1 Ma, intermediate between the Aragonian dryopithecins and the Vallesian hispanopithecins. Ongoing paleontological surveillance at ACM thus offers the prospect to yield additional earliest Vallesian ape remains, which are essential to clarify their taxonomic allocation as well as to confirm whether hispanopithecins evolved locally from dryopithecins rather than immig

The Pyrenees constitutes an exceptional example of an Alpine orogenic belt characterized by basement thrust sheets involving Paleozoic rocks and Mesozoic and Cenozoic cover units detached on the Triassic evaporites, the main décollement level. This work is located in the Central Pyrenees, where gravity data help to better constrain the internal architecture of the upper crust of the southern half of the Axial Zone and the northern part of the South Pyrenean Zone, a key area to understand the orogenic evolution of the chain. Previous and new gravity, petrophysical and geological data have been used to obtain the Bouguer and residual anomaly maps of the study area and six serial gravity-constrained cross sections perpendicular to the main structural trend. The residual anomaly map shows a good correlation between basement units involved in thrust sheets of the study area and gravity highs whereas negative anomalies are interpreted to correspond with Mesozoic/Cenozoic basins, Triassic evaporites, Late Variscan igneous bodies, and Ordovician gneisses. The six gravity-constrained cross sections highlight strong along-strike variations on the gravity signal due to lateral differences of the superficial and subsurface occurrence of Triassic evaporites, different geometry at depth of the Late Variscan igneous bodies outcropping in the study area, and geometric lateral variations of the basement thrust sheets and their relationship with the Mesozoic-Cenozoic units.

Els Casots is one of the richest fossil vertebrate sites of the Vallès-Penedès Basin (Catalonia, Spain). It was discovered in 1989 and excavated briefly during the 1990s, resulting in the recovery of thousands of remains and the erection of several new mammal species. Excavations were resumed in 2018 and continue to date. Here we provide updated results regarding the age, stratigraphy, biota and palaeoenvironment of the site. The age of the site is well constrained to ~15.9 Ma thanks to recent bio- and magnetostratigraphic data, thus coinciding with the Miocene Climatic Optimum (MCO). The stratigraphic succession at the site area indicates lacustrine to palustrine environments with cyclically oscillating water level. There are several fossiliferous layers that have yielded a vertebrate fauna comprising up to 75 different vertebrate species including amphibians, reptiles, birds and mostly mammals. The finding of several articulated partial skeletons indicate that the site records an autochthonous to parautochthonous assemblage. The abundance and completeness of the vertebrate remains together with a well-constrained age and detailed stratigraphic and palaeoenvironmental data, make els Casots a key site for understanding wetland ecosystems in southern Europe during the MCO.