Person: Horra Del Barco, Raúl De La
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First Name
Raúl De La
Last Name
Horra Del Barco
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Geológicas
Department
Geodinámica, Estratigrafía y Paleontología
Area
Estratigrafía
Identifiers
21 results
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Item Sedimentary evolution of the continental Early–Middle Triassic Cañizar Formation (Central Spain): Implications for life recovery after the Permian–Triassic crisis(Sedimentary Geology, 2012) López Gómez, José; Galán Abellán, Ana Belén; Horra Del Barco, Raúl De La; Fernández Barrenechea, José María; Arche, Alfredo; Bourquin, Sylvie; Marzo Carpio, Mariano; Durand, MarcThe Permian–Triassic transition (P–T) was marked by important geochemical perturbations and the largest known life crisis. Consequences of this event, as oxygen-depleted conditions and the unusual behavior of the carbon cycle, were prolonged during the Early Triassic interval delaying the recovery of life in both terrestrial and marine ecosystems. Studies on Lower Triassic sediments of continental origin, as in the case of Western Europe, are especially problematic due to the scarcity of fossils and absence of precise dating. The Cañizar Fm. is an Early–Middle Triassic unit of continental origin of the SE Iberian Ranges, E Spain. A detailed sedimentary study of this unit allows a shedding of light on some unresolved problems of the continental deposits of this age. The top of this unit is dated as early Anisian by means of a pollen association, while the age of its base is here estimated as late Smithian or Smithian–Spathian transition. Different facies associations and architectural elements have been defined in this unit. In the western and central parts of the basin, this unit shows sedimentary characteristics of fluvial deposits with locally intercalated aeolian sediments, while in the eastern part there is an alternation of both aeolian and fluvial deposits. Sedimentary structures also indicate changes in the climate conditions, mainly from arid to semiarid. Two marked arid periods when well-preserved aeolian sediments developed during early–middle Spathian and Spathian–Anisian transition. They alternated with two semiarid but more humid periods during the late Spathian and early Anisian. These conditions basically correspond with the general arid and very arid conditions described for central–western European plate during the same period of time. The Ateca–Montalbán High, in the northern border of the study basin, must have represented an important topographic barrier in the western Tethys separating aeolian dominated areas to the N and NE from fluvial dominated areas to the south. The Cañizar Fm. has been subdivided into six members (A–F) separated by seven (1–7) major bounding surfaces (MBS). These surfaces are well recognized laterally over hundred of km and they represent 104–105 My. MBS-5 is considered to be of late Spathian age and it is a clear indication of tectonic activity, represented by a mild unconformity. This event represents a change in the sedimentary characteristics (reactivation) of the unit and from here to the top of the unit are found the first signals of biotic recovery, represented by tetrapod footprints, plants, roots and bioturbation. All of these characteristics and the estimated age represented by the MBS-5 event permit this surface to be related to the coeval Hardegsen unconformity of Central–Western Europe. These first signals of biotic recovery can thus be related to an increased oxygen supply due to the new created paleogeographical corridors in the context of this tectonic activity. These biotic signals occurred 5 My after the Permian–Triassic limit crisis; a similar delay as occurred in other coeval and neighboring basins.Item The beginning of the Buntsandstein cycle (Early–Middle Triassic) in the Catalan Ranges, NE Spain: Sedimentary and palaeogeographic implications(Sedimentary geology, 2013) Galán Abellán, Ana Belén; López Gómez, José; Barrenechea, José F.; Marzo Carpio, Mariano; Horra Del Barco, Raúl De La; Arche, AlfredoThe Early–Middle Triassic siliciclastic deposits of the Catalan Ranges, NE Spain, are dominated by aeolian sediments indicating a predominance of arid climate during this time span, in sharp contrast with the coeval fluvial sediments found in the Castilian Branch of the Iberian Ranges, 300 km to the SW. The NE–SW-oriented Catalan Basin evolved during the Middle–Late Permian as the result of widespread extension in the Iberian plate. This rift basin was bounded by the Pyrenees, Ebro and Montalbán–Oropesa highs. The Permian–Early Triassic-age sediments of the Catalan Basin were deposited in three isolated subbasins (Montseny, Garraf, Prades), separated by intrabasinal highs, but linked by transversal NW–SE oriented faults. The three subbasins show evidence of diachronic evolution with different subsidence rates and differences in their sedimentary records. The Buntsandstein sedimentary cycle started in the late Early Triassic (Smithian–Spathian) in the central and southern domains (Garraf and Prades), with conglomerates of alluvial fan origin followed by fluvial and aeolian sandstones. Source area of the fluvial sediments was nearby Paleozoic highs to the north and west, in contrast with the far-away source areas of the fluvial sediments in the Iberian Ranges, to the SW. These fluvial systems were interacting with migrating aeolian dune fields located towards the S, which developed in the shadow areas behind the barriers formed by the Paleozoic highs. These highs were separating the subbasins under arid and semi-arid climate conditions. The dominating winds came from the east where the westernmost coast of the Tethys Sea was located, and periods of water run-off and fields of aeolian dunes development alternated. Some of the fluvial systems were probably evaporating as they were mixed into the interdune areas, never reaching the sea. From the end of the Smithian to the Spathian, the Catalan Basin and neighbour peri-Tethys basins of the presentday southern France, Sardinia andMinorca islands constituted a geographical archwhere arid and semi-arid conditions represented an extension of the prevailed arid and hyper-arid conditions in surrounding areas of the Variscan Belt. Harsh climatic conditions in this area prevented the life recovery in the aftermath of the Permian– Triassic extinction event until the early Anisian, when more humid climate allowed for the colonisation of the area by plants, amphibians and reptiles. The boundary between desert areas and semi-arid and/or seasonal climate domains during the Smithian–Spathian in SW Europe can be precisely established in NE Iberia, between the Catalan–Ebro region and the Castilian Branch of the Iberian Ranges, to the SW.Item U-Pb Ages of Detrital Zircons from the Permo-Triassic Series of the Iberian Ranges: A Record of Variable Provenance during Rift Propagation(The Journal of geology, 2012) Sánchez Martínez, Sonia; Horra Del Barco, Raúl De La; Arenas Martín, Ricardo; Gerdes, A.; Galán Abellán, Ana Belén; López Gómez, José; Fernández Barrenechea, José María; Arche, AlfredoThe provenance of the Permo-Triassic series of the Talayuelas anticline (Iberian Ranges) have been studied using UPb geochronology (laser ablation inductively coupled plasma mass spectrometry) of detrital zircons. These intracontinental siliciclastic series were formed by extensive sandy braided fluvial systems associated with ephemeral lake deposits and aeolian sediments, with paleocurrents suggesting constant NW-SE transport directions. Upper Permian reddish sandstones from the Upper Alcotas Formation (Lopingian) contain a dominant Variscan zircon population (290–360 Ma), which indicates source areas located in the axial zone of the Variscan belt, in the core of the Ibero- Armorican arc. However, in the Lower Triassic sandstones of the Canñizar Formation (Olenekian), the Variscan zircon population is almost completely replaced by Cadomian zircons (520–750 Ma), with important Avalonian (390–520 Ma), Mesoproterozoic (900–1750 Ma), Eburnian (1.78–2.35 Ga), and post-Eburnian and Archaean (12.4 Ga) zircon populations. This detrital zircon content now suggests source areas located more to the NW, in the Avalonian microcontinent, although a limited supply coming from the southern part of Laurentia cannot be ruled out. Finally, in the Middle Triassic (Anisian), the source areas returned to the Variscan axial zone, since the Variscan zircon population is again highly dominant during this period. The changes detected in the source areas of the Permo-Triassic series are related to the development and propagation of the Iberian rift, one of the large extensional structures that determined the generation of the sedimentary basins and finally caused the breakup of Pangea. The methodology followed in this article is very useful to understand the generation and evolution of these intracontinental basins and also the relationships between the different rift systems generated in the North Atlantic realm during the Permo- Triassic times.Item Gradual changes in the Olenekian-Anisian continental record and biotic implications in the Central-Eastern Pyrenean basin, NE Spain(Global and Planetary Change, 2020) Lloret, Joan; Horra Del Barco, Raúl De La; Gretter, Nicola; Borruel Abadía, Violeta; Fernández Barrenechea, José María; Ronchi, Ausonio; Diez, José B.; Arche, Alfredo; López Gómez, José TrinidadThis work focuses on the Olenekian-Anisian (Early-Middle Triassic) continental record of the Central-Eastern Pyrenean basin (NE Spain), a near-equator (10°-14°N) basin located in the western peri-Tethys margin, inside the Variscan fold-belt. Due to the mass mortality of the end-Permian and the subsequent Smithian-Spathian Boundary (SSB) crisis, the Early Triassic and its transition to the Middle Triassic was a time period with intermittent stages of environmental instability that affected fauna and flora intensely. Compared to other crisis, a remarkable feature is the longer time required to achive life recovery during this time-interval and the fact that continental environments have been less globally studied than their marine counterparts. Furthermore, in SW Europe there is almost no sedimentary continental record from the beginning of the Triassic. This multidisciplinary study, embracing sedimentology, mineralogy, palaeontology, palaeopedology and palaeogeography, of 10 complete and well dated Early-Middle Triassic field sections has allowed (1) the location and characterization of the oldest Mesozoic sedimentary record in the basin, which is of late Smithian age and overlies the late-middle Permian continental rocks and of (2) the Smithian-Spathian transition (SST), (3) the timing of life recovery during the late Spathian-Anisian, (4) the characterization of the first incursion of the Tethys sea into the basin, and (5) the comparison of the evolution of this basin with other basins of the same age in SW Europe. The SST coincides with hyper-arid climate conditions, evolving to semi-arid in the late Spathian and semi-arid to semi-humid in Anisian times. Poorly sorted breccias and conglomerate alluvial sheets with aeolian reworking dominate the SST, as a result of these environmental changes and tectonicsA broader comparison, based on stratigraphic studies by other authors, indicates less aridity in the basin studied compared to other SW Europe basins in the same period, maybe due to its greater proximity to the equator. Sedimentary characteristics changed during the late Spathian, when sandy braided fluvial systems developed and the first dispersed plants, pollen assemblages and paleosols appeared. Well-developed floodplains and associated paleosols and plants developed during the early Anisian, when more humid conditions prevailed. The occurrence of aluminium phosphate-sulphate (APS) minerals might be considered as evidence of environmental acidification during the Olenekian with an amelioration during the early Anisian, as described in neighboring basins, although in the Pyrenean basin this acidification was probably less intensive. The first incursion of the Tethys sea reached the Central-Eastern Pyrenean basin during the Anisian-Ladinian transition, about 3 My later than in neighbouring Southwestern Europe basins. General comparison with other Early-Middle Triassic continental records of Western Europe basins indicates contrasting trends of climate and sedimentary evolution, probably related to the still prevailing great paleorelief of the Variscan foldbelt, where part of the study basin could constitute an elevated area during some time-intervals, possibly related to the so-called Ebro High.Item Impact of Permian mass extinctions on continental invertebrate infauna(Terra Nova, 2021) Buatois, Luis A.; Borruel Abadía, Violeta; Horra Del Barco, Raúl De La; Galán Abellán, Ana Belén; Fernández Barrenechea, José María; Arche, AlfredoThe Capitanian (late middle Permian) and end‐Permian mass extinctions were particularly severe from a palaeoecological perspective. Previous studies of their expressions on land underscored their impacts on plants and vertebrates, but the effects on the continental invertebrate infauna remain poorly understood. A multiproxy analysis from the Iberian Basin (Central Spain) reveals a dramatic decrease in bioturbation intensity on land by the end of the Capitanian. This pattern cannot be explained by facies effects because our analysis is based on similar types of deposits through the succession and over an extensive area. The bioturbation crisis coincided with an increase in weathering intensity and acidic conditions, and a collapse in plant communities spanning the late Permian–Early Triassic in the Iberian Basin. Reduced bioturbation may have contributed to decrease in mechanical reworking of the sediment and soil, affected geochemical recycling, increased sediment acidification and impacted on ecosystem structure. Identification of this infaunal crisis on land underscores the ecological severity of mass extinctions and emphasises the significance of feedback loops in riparian ecosystems.Item New ichnites from the Middle Triassic of the Iberian Ranges (Spain): paleoenvironmental and paleogeographical implications(Historical Biology, 2010) Ganda, Georges; Horra Del Barco, Raúl De La; Galán-Abellán, Belén; López Gómez, José; Fernández Barrenechea, José María; Arche, Alfredo; Benito Moreno, María IsabelThe Iberian Basin or its present-day expression, the Iberian Ranges, was refilled with red bed sediments of alluvial origin during the late Olenekian–Anisian period represented by the Cañizar (Olenekian–Anisian) and Eslida (Anisian) Formations, both commonly known as Buntsandstein facies. In the late part of the Anisian, the Tethys Sea reached the eastern side of the Iberian microplate, represented by the shallow marine facies of the Landete and Cañete Formations, also called Muschelkalk facies. The ichnites studied in this paper belong to the Anisian continental-marine transition in the SE Iberian Ranges. The Cañizar Formation shows the oldest Triassic footprints found in the Iberian Peninsula, consisting in swimming, uncomplete lacertoid three digit Rhynchosauroides traces with possibly resting (cubichnia) and furrowing (pascichnia) Cruziana/Rusophycus due to large triopsids. Specimens from Lacertoïd and Crocodiloïd groups have been collected in the Eslida Formation. Rhynchosauroides sp. is the most representative ichnospecies of the first group, while in the Crocodiloïd group, the presence of Chirotherium barthii Kaup 1835 and Isochirotherium cf coureli (Demathieu 1970) are distinctive. In the Landete Formation specimens are found from Crocodiloïd and Dinosauroïd groups. Brachychirotherium gallicum Willruth 1917, Brachychirotherium sp. and Chirotherium sp. are characteristic of the first one, and ‘Coelurosaurichnus’ perriauxi and cf Paratrisauropus latus as the most representative of the second group. Some of the specimens described here present ancestors in the Early Triassic and have been described in the Triassic of North America, Italy and France. Possible paleogeographical connections with faunas of SE France can be inferred. Based on different sedimentary structures and plant remains, the footprints are related to fluvial systems within huge flood plains, playa and shallow marine environments, with alternating dry and wet periods. The vertical ichnites distribution during the Anisian shows that the fauna modification was weak at a high clade level. In the Triassic of the Iberian microplate, there are no findings of traces prior to the Anisian, and the footprint content for the Middle Triassic is less diversified than in other neighbouring regions. By comparison with other western Pangea areas, there was a later appearance of the forms after the end-Permian mass extinction event in the studied areaItem Palynostratigraphy of the Middle Triassic (Anisian) Eslida Formation, SE Iberian Ranges, Spain(Palynology, 2017) Fernández Barrenechea, José María; Juncal, Manuel; Horra Del Barco, Raúl De La; Borruel Abadía, Violeta; Arche, Alfredo; López-Gómez, José; Diez, José BThe Triassic record in the SE Iberian Ranges starts with two tecto-sedimentary units of continental origin in Buntsandstein facies: and Cañizar and Eslida Formations. The Eslida Formation consists of sandstone bodies intercalated with thick, red siltstone beds. Where this unit is presented, it lies always conformably layers on top of the Cañizar Formation and it grades upwards into overlying coastal mud flats, traditionally assigned to the Röt facies. In the past, accurate dating of the Eslida Formation has been sometimes problematic because of its continental character, absence of datable fossil remains, and lithological similarities with Middle-Upper Permian rocks. Macroflora and fossilised vertebrate footprints in the Eslida Formation indicate an Anisian age (Middle Triassic), in concordance with its stratigraphic position, as both the underlying and overlying units are also Anisian in age. In this work, we date the Eslida Formation on the basis of a palynological assemblage, obtained from a locality near the city of Teruel (SE Iberian Ranges), that includes: Alisporites grauvogeli, Alisporites oppii, Calamospora tener, Concentricisporites neversii, Cyclotriletes oligogranifer, Hexasaccites muelleri, Illinites kosankei, Lunatisporites noviaulensis, Punctatisporites fungosus and Voltziaceaesporites heteromorpha. This palynological association suggests an Anisian age, more precisely a period of time close to the Bithynian-Pelsonian transition. The precise dating of the Eslida Formation is essential in order to establish stratigraphical correlations with other units in the Iberian Ranges and to obtain paleogeographical considerations on the rapid subsidence represented by the sedimentary record of this unit in the new N.NE-S.SE Middle Triassic rift developed in eastern Iberia.Item The Late Palaeozoic-Early Mesozoic from the Catalan Pyrenees (Spain): 60 Myr of environmental evolution in the frame of the western peri-Tethyan palaeogeography(Earth-Science Reviews, 2015) Gretter, N.; Ronchi, A.; López Gómez, José; Arche, Alfredo; Horra Del Barco, Raúl De La; Barrenechea, José F.; Lago San José, MarcelianoThe Eastern Catalan Pyrenees form the southernmost segment of the Pyrenean Axial Zone. They experienced complex multistage process as the result of both the Variscan and the Pyrenean orogenic cycles. After the Late Palaeozoic, several small extensional sub-basins were filled by continental successions as a response to the changing tectonic setting within the frame of the Southwestern Europe. This stratigraphic record, perfectly exposed in the studied Eastern Pyrenean areas, preserves the signatures of the Late Palaeozoic Pangea break-up during the progressive dismantling of the Variscan chain, up to the Triassic diffused extension. Despite structural network being severely affected by Cenozoic reworking, the stratigraphic framework can be unravelled by the detailed sedimentological and stratigraphical analysis of the well-exposed sequences. In short, this paper addresses facies patterns and architectural elements of Late Carboniferous-Permian-Triassic continental sections studied in the Catalan Pyrenees and aims to use these signatures for correlation not only at a regional scale but also within the broader picture of the southwestern Europe. Our stratigraphical reconstruction clearly demonstrates that the thick studied succession consists of fluvial-lacustrine basal units affected by intense volcanic activity and overlaying predominantly fluvial fining upwards units. For each unit several lithofacies, architectural elements and bounding surfaces of different order have been identified and their lateral and vertical staking characterized. Deposition and erosion processes are controlled by alternating periods of tectonic activity producing different stages of high and low subsidence, the uplift of the sub-basin margins and subsequent extended erosive events marked by angular unconformities. On the strength of the major rank bounding surfaces analysis, the studied sedimentary packages have been grouped into different tectono-stratigraphic units and then correlated; they have been contextualized within the latest palaeogeographic reconstructions of the studied sector, contributing to detail the role of the study area within the frame of the S European palaeogeography.Item Comment on “Integrated multi-stratigraphic study of the Coll de Terrers late Permian–Early Triassic continental succession from the Catalan Pyrenees (NE Iberian Peninsula): A geologic reference record for equatorial Pangaea” by Eudald Mujal, Josep Fortuny, Jordi Pérez-Cano, Jaume Dinarès-Turell, Jordi Ibáñez-Insa, Oriol Oms, Isabel Vila, Arnau Bolet, Pere Anadón. Global and Planetary Change 159 (2017) 46–60(Global and Planetary Change, 2019) Ronchi, Ausonio; Lloret, Joan; Gretter, Nicola; López Gómez, José; Horra Del Barco, Raúl De La; Barrenechea, José F.; Arche, AlfredoIn their paper, Mujal et al. (2017) describe as exceptional a section in the E Pyrenees (namely the Coll de Terrers), considering it a continental succession that continuously spans in time from the Late Permian to the Early Triassic. These authors describe the sandy-clayey red-beds of the upper Buntsandstein unit as the upper part of the Upper Red Unit (URU) and provide substantial stratigraphic and sedimentological data as well as palaeontological and mineralogical data in support of their thesis. We firstly have to consider that the post-Variscan deformation events altered the sedimentary contacts among the units (i.e. subsidence and tectonic evolution of the related sub-basins); and secondly, that the entire succession contains several tectonic structures affecting the late Palaeozoic-early Mesozoic sequence, due to the Alpine orogeny. The purported stratigraphic continuity between the Permian and Triassic is thus hampered not only by a different sedimentological and stratigraphical content but also by a complex tectonic framework.Item New Upper Carboniferous palynofloras from Southern Pyrenees (NE Spain): Implications for palynological zonation of Western Europe(Palaeogeography, Palaeoclimatology, Palaeoecology, 2019) Juncal Rosales, Manuel Antonio; Lloret, Joan; Diez, José B.; López Gómez, José; Horra Del Barco, Raúl De La; Barrenechea, José F.; Arche, AlfredoIn the western European basins, the paleoflora of late Pennsylvanian-early Permian transition is still a matter of discussion in terms of its age determination and biostratigraphic ranges. This study represents a review of the Upper Carboniferous and Permian stratigraphy of the Central and Eastern Pyrenees from continental successions with interbedded volcanic-volcaniclastic rocks, coupling new palynological data and known palynological assemblages to calibrate them with recent SHRIMP U-Pb zircon ages dates obtained in previous works. In this light, the first continental unit overlying the Variscan basement bears a Gzhelian palynological association, which fits perfectly with the isotopic SHRIMP U-Pb zircon dating of the associated pyroclastic rocks (304.6 ± 1.5 Ma and 300.4 ± 1.4 Ma). In order to provide a solid base to characterize the Carboniferous-Permian microflora evolution in the western Tethys sub-basins, we have compared radiometrically dated palynological assemblages of the Euramerican Province such as Spain, southern France, the Alps and Sardinia (Italy). The new biostratigraphic and chronostratigraphic information presented here confirms the validity of the classical Carboniferous Palynological Zonation of Western Europe.
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