Person:
Horra Del Barco, Raúl De La

First Name

Raúl De La

Last Name

Horra Del Barco

URI

https://hdl.handle.net/20.500.14352/75215

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Ciencias Geológicas

Department

Geodinámica, Estratigrafía y Paleontología

Area

Estratigrafía

Identifiers

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Now showing 1 - 10 of 40

Mid-Albian to earliest Cenomanian climate cycles indicated by humid paleosols developed within the arid braidplain facies of the Utrillas Group of east-central Spain
(Palaeogeography, Palaeoclimatology, Palaeoecology, 2023) Bueno Cebollada, Carlos A.; Horra Del Barco, Raúl De La; Fernández Barrenechea, José María; Meléndez Hevia, María Nieves; Barrón López, Eduardo; Fregenal Martínez, María Antonia
The development of arid climate conditions in eastern Iberia during the mid-Cretaceous (mid-Albian to earliest Cenomanian) has been postulated by several authors over the last two decades based on sedimentological and palaeobotanical datasets. In this paper, we present a combined sedimentological and paleosol study of the mid-Albian to earliest Cenomanian Utrillas Group in the Cuenca Basin of east-central Spain, to improve knowledge of palaeoclimate. Four facies associations are identified as follows: Proximal alluvial braidplain (FA I), Distal alluvial braidplain (FA II), Aeolian dunes (FA III), and Inner estuarine settings (FA IV). The succession records the development of a braidplain system under dominantly arid conditions followed by a marine transgressive phase. In contrast to the overall arid palaeoclimate interpretation, multi-proxy palaeoedaphological analyses conducted for three paleosol profiles (Spodosols) indicate the occurrence of periods of increased humidity in the basin. These findings allow us to infer the occurrence of shorter-term climatic oscillations characterised by a tropical savanna climate when the palaeosols developed, suggesting significantly more humid conditions than those inferred based on the sedimentological and previous palaeobotanical datasets. We propose a palaeoclimatic model that explains the alternation between the dominantly arid and these more humid periods based on the cyclical latitudinal shifting of the mid-Cretaceous climatic belts, shedding new light on the mid-Albian to earliest Cenomanian climate of Iberia.
Permian-Triassic continental rocks of the SE Iberian Ranges: Architecture, tectonics and geochemical characteristics in the context of a rift basin
(2011) López Gómez, Julián; Arche, A.; Horra Del Barco, Raúl De La; Galán-Abellán, B.; Fernández Barrenechea, José María
Characterization of the Carnian Pluvial Episode in the Argana Basin (Western High Atlas, Morocco): An approach based on sedimentology, clay mineralogy and paleosols
(Palaeogeography, Palaeoclimatology, Palaeoecology, 2023) Tourani, A.; Benaouiss, N; Horra Del Barco, Raúl De La; Fernández Barrenechea, José María; Gallego, O. F.; López Gómez, J.; Bourquin, S.
We report on a multi-proxy study of the Carnian Pluvial Episode in the continental Argana Basin (Morocco) based on mineralogy, geochemistry, paleosols and sedimentary features. The study focus on two sections of the Irohalene Member (unit t5) of the Timezgadiouine Formation dated as late Julian-early Tuvalian through clam shrimp (conchostracan) associations. The sedimentary study of the Irohalene Member defines three parts: lower, middle and upper (t5.1, t5.2, t5.3 respectively). The base of the lower part comprises channels with gravel and sandy bars related to proximal areas, and fluvial meandering systems, overbank and floodplain deposits developing upwards. Extensive floodplains showing the development of siliciclastic and carbonate lakes mostly represent the t5.2 and t5.3 parts, although the sedimentary characteristics of the former reflect more humid and permanent water conditions. These more humid characteristics are also indicated by the drastic change from calcareous paleosols in t5.1 to smectitic Vertisols in t5.2, which occur in relation to thin layers of lacustrine carbonates, greenish lutites, and hybrid oolitic sandstones of palustrine environments. Stable carbon and oxygen isotope data are consistent with a general tendency towards the arid conditions observed in the Tadart Ouadou t6 Member of the Bigoudine Formation, of fluvial-eolian origin and younger in age. This general tendency is interrupted by at least two humid yet hot intervals characterized by pedogenic carbonates featuring lighter isotope compositions and lacustrine carbonates precipitated under conditions of high temperatures and evaporation rates.
Palynological and sedimentological implications of the sauropterygian Upper Triassic site of El Atance (Central Iberian Peninsula)
(Review of palaeobotany and palynology, 2021) García Ávila, Manuel; Horra Del Barco, Raúl De La; Miguel Chaves, Carlos de; Juncal, Manuel A.; Pérez García, Adán; Ortega, Francisco; Diez, José B.
This study presents new palynological and sedimentological data concerning the Upper Triassic outcrop El Atance (Guadalajara province, Spain). This fossil site has provided a unique and unprecedented concentration of reptile skeletons from the Late Triassic in the Iberian Peninsula, which are almost complete, articulated and preserved in three dimensions. It is the type locality of the simosaurid nothosauroid Paludidraco multidentatus and the henodontid placodont Parahenodus atancensis, being the only species of these clades represented with some certainty in the Iberian record. Although these reptiles are often linked to shallow marine environments, little is known about the sedimentary environment where they became fossilized. Furthermore, to compare these remains with those from other areas of Europe, greater precision in their age assignment is necessary. The new palynological data provided in this study allows us to assign a precise age, in addition to other data such as a probable plant community, palaeoecology, and palaeoclimatic conditions. This information together with the geological and sedimentological data and the new isolated sauropterygian remains studied, allow a better understanding of the local palaeogeography and the evolutionary history of the vertebrates found in the El Atance fossil site.
Palynostratigraphy of the Middle Triassic (Anisian) Eslida Formation, SE Iberian Ranges, Spain
(Palynology, 2018) Juncal Rosales, Manuel Antonio; Diez, José B.; Horra Del Barco, Raúl De La; Galán Abellán, Ana Belén; Borruel Abadía, Violeta; Fernández Barrenechea, José María
The 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 always lies conformably 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 was 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 this work, we date the Eslida Formation on the basis of a palynological assemblage. 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 palaeogeographical considerations on the rapid subsidence represented by the sedimentary record of this unit in the new NNE–SSE Middle Triassic rift developed in eastern Iberia.
The Anisian continental-marine transition in Sardinia (Italy): state of the art, new palynological data and regional chronostratigraphic correlation
(Journal of iberian geology, 2022) Stori, L.; Diez, J. B.; Juncal Rosales, Manuel Antonio; Horra Del Barco, Raúl De La; Borruel Abadía, Violeta; Martín Chivelet, Javier; Fernández Barrenechea, José María; López Gómez, José; Ronchi, Ausonio
The scarce evidence of paleontological records between the upper Permian and the Anisian (Middle Triassic) of Western Europe could reflect (1) large stratigraphic gaps in the continental successions and/or (2) the persistence of disturbed conditions after the Permian–Triassic Boundary extinction event and the succession of ecological crises that occurred during the Early Triassic. In this context, the study of palynological associations, integrated with the stratigraphical and sedimentological data, plays a key role in dating and correlating the successions of the Western European domain and improves our understanding of environmental and paleoclimatic conditions. In some cases, pre-Anisian paleontological evidence is lacking, as in Sardinia (Italy), where a long gap encompasses the middle Permian (pars) to late Lower Triassic successions. Although fragmented and disseminated, the continental Lower-Middle Triassic sedimentary successions (Buntsandstein) of Sardinia have proved crucial to our understanding of the evolution of the southern edge of the Paleo-Europe and the different timings of the Tethys transgression (Muschelkalk facies) in some of these areas. Various paleogeographic reconstructions were attempted in previous works, without providing any consensus on the precise position of Sardinia and its surrounding seaways in the Western Tethys domain during this time interval. At present, the configuration and distribution of the subsiding and emerging landmasses and the temporal development of the transgressions of the Western Tethys during the Middle Triassic remain unclear. This work focuses on the stratigraphical, sedimentological and palynological aspects of three Middle Triassic continental-marine sedimentary successions in Sardinia, with particular attention to the analysis of the palynological associations sampled there, and it also provides a detailed review of all previous palynological publications on the Sardinian Anisian. The studied successions are: Su Passu Malu section (Campumari, SW Sardinia), Arcu is Fronestas section and Escalaplano section (Escalaplano, Central Sardinia). These sections were also correlated to other significant sections in the SW (Scivu Is Arenas) and NW (Nurra) parts of the island.
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, Marc
The 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.
Sedimentology, clay mineralogy and palaeosols of the Mid-Carnian Pluvial Episode in E Spain: insights into humidity and sea-level variations
(Journal of the Geological Society, 2018) Barrenechea, José F.; López Gómez, José; Horra Del Barco, Raúl De La
This study examines rainfall variations of the Mid-Carnian Pluvial Episode (CPE) based on the continental fluvial sedimentology, palaeosol and clay mineralogy records of the Stable Meseta (E Spain). In the formation examined, Manuel Fm or K2 Fm, the CPE is represented by three regressive-transgressive sequences (R-T), or subunits K2.1, K2.2 and K2.3, from base to top. Each subunit broadly consists of a genetic stratigraphic sequence bearing well-developed highstand, lowstand and transgressive system tracts (HST, LST and TST). Hydromorphic features in the palaeosols suggest changes in the activity of both ground and surface waters. The clay mineral assemblage is dominated by illite, with a minor presence of kaolinite and traces of smectite in some samples. After ruling out tectonism in the study area, climate and eustatism emerge as the main allogenic controls in the sedimentary record. Differentiated sedimentary facies and architectural elements in the K2.2 subunit were likely controlled by both a more humid climate and source area, while K2.1 and K2.3 were more related to base-level changes and eustatic control. The presence of more waterlogged pedotypes and of kaolinite and traces of smectite in the clay mineral assemblage of K2.2 also indicates increased humidity. Notwithstanding, our data do not point to intense rainfall periods for the CPE in E Spain.
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, Alfredo
The 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.
Transition between Variscan and Alpine cycles in the Pyrenean-Cantabrian Mountains (N Spain): Geodynamic evolution of near-equator European Permian basins
(Global and Planetary Change, 2021) Lloret, Joan; López Gómez, José; Heredia, N.; Martín González, Fidel; Horra Del Barco, Raúl De La; Borruel Abadía, Violeta; Ronchi, Ausonio; Fernández Barrenechea, José María; García-Sansegundo, Joaquín; Galé, Carlos; Ubide, Teresa; Gretter, Nicola; Diez, José B.; Juncal Rosales, Manuel Antonio; Lago, Marceliano
In the northern Iberian Peninsula, the Pyrenean-Cantabrian orogenic belt extends E-W for ca. 1000 km between the Atlantic Ocean and Mediterranean Sea. This orogen developed from the collision between Iberia and Eurasia, mainly in Cenozoic times. Lower-middle Permian sediments crop out in small, elongated basins traditionally considered independent from each other due to misinterpretations on incomplete lithostratigraphic data and scarce radiometric ages. Here, we integrate detailed stratigraphic, sedimentary, tectonic, paleosol and magmatic data from well-dated lithostratigraphic units. Our data reveal a similar geodynamic evolution across the Pyrenean-Cantabrian Ranges at the end of the Variscan cycle. Lower-middle Permian basins started their development under an extensional regime related to the end of the Variscan Belt collapse, which stars in late Carboniferous times in the Variscan hinterland. This orogenic collapse transitioned to Pangea breakup at the middle Permian times in the study region. Sedimentation occurred as three main tectono-sedimentary extensional phases. A first phase (Asselian-Sakmarian), which may have even started at the end of the Carboniferous (Gzhelian) in some sections, is mainly represented by alluvial sedimentation associated with calc-alkaline magmatism. A second stage (late Artinskian–early Kungurian), represented by alluvial, lacustrine and palustrine sediments with intercalations of calc-alkaline volcanic beds, shows a clear upward aridification trend probably related to the late Paleozoic icehouse-greenhouse transition. The third and final stage (Wordian-Capitanian) comprised of alluvial deposits with intercalations of alkaline and mafic beds, rarely deposited in the Cantabrian Mountains, and underwent significant pre- and Early Mesozoic erosion in some segments of the Pyrenees. This third stage can be related to a transition towards the Pangea Supercontinent breakup, not generalized until the Early/Middle Triassic at this latitude because the extensional process stopped about 10 Myr (Pyrenees) to 30 Myr (Cantabrian Mountains). When compared to other well-dated basins near the paleoequator, the tectono-sedimentary and climate evolution of lower-middle Permian basins in Western and Central Europe shows common features. Specifically, we identify coeval periods with magmatic activity, extensional tectonics, high subsidence rates and thick sedimentary record, as well as prolonged periods without sedimentation. This comparison also identifies some evolutionary differences between Permian basins that could be related to distinct locations in the hinterland or foreland of the Variscan orogen. Our data provide a better understanding of the major crustal re-equilibration and reorganization that took place near the equator in Western-Central Europe during the post-Variscan period.