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Limarino, Carlos Oscar - One of the best experts on this subject based on the ideXlab platform.
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El magmatismo Choiyoi en el sudoeste de Gondwana: Su implicancia en la extinción en masa del Pérmico tardío - una revisión
2019Co-Authors: Spalletti, Luis Antonio, Limarino, Carlos OscarAbstract:The end of the Permian period is marked by global warming and the biggest known mass extinction on Earth. The crisis is commonly attributed to the formation of large igneous provinces because continental volcanic emissions have the potential to control atmospheric carbon dioxide (CO2) levels and climate change. We propose that in southwestern Gondwana the long-term hothouse Permian environmental conditions were associated with the development of the Choiyoi magmatism. This large igneous province was developed between the Cisuralian and the early Triassic. It covers an area estimated at 1,680,000 km2 with an average thickness of 700 m, so that the volume of effusive and consanguineous rocks is estimated at 1,260,000 km3. Towards the western sector of the study region, a major overlap exists between the regional development of the Choiyoi magmatism and the Carboniferous sedimentary basins, which include paralic and continental deposits with intercalations of peat and coal beds. Commonly, these upper Palaeozoic deposits accumulated on a thick substrate composed of Cambro-Ordovician carbonates and Ordovician to Devonian terrigenous sedimentary rocks characterised by a large proportion of dark organic-rich shales and turbidite successions. While extensive volcanism released large masses of carbon dioxide into the Permian atmosphere, the heating of Palaeozoic organic-rich shales, peat and carbonates by ascending magma led to CO2 and CH4 gas generation in sufficient volumes to amplify the major climatic change. The analysis of the almost continuous record of Permian redbeds in the Paganzo basin, where the Choiyoi magmatism is not recorded, allowed us to recognize two main pulses of strong environmental desiccation, one at the Cisuralian and the second around the end-Permian. These two drastic climatic crisis are attributed to peaks of CO2 and CH4 outbursts to the atmosphere and related collateral effects, such as acid rain, impoverishment of soils and increase in forest-fire frequency. We propose that the combination of these multiple mechanisms triggered the decline of biodiversity in southwestern Gondwana and caused the end-Permian extinction of most of the Glossopteridales.El final del Pérmico está caracterizado por un proceso de calentamiento global que llevó a la mayor extinción en masa registrada en la Tierra. Esta crisis se atribuye comúnmente a la generación de grandes provincias ígneas en ámbito continental, cuyas emisiones volcánicas han controlado los niveles de CO2 en la atmósfera y el consecuente cambio climático. En este trabajo se propone que las condiciones fuertemente cálidas (hothouse) del Pérmico en el sudoeste de Gondwana estuvieron asociadas con el desarrollo del magmatismo Choiyoi. Esta provincia ígnea, que se desarrolló durante el lapso Cisuraliano-Triásico temprano, cubrió un área estimada en 1.680.000 km2 con un espesor medio de 700 m, de modo que los volúmenes de rocas efusivas y consanguíneas se estiman en alrededor de 1.260.000 km3. Hacia el sector occidental de la región de estudio, se registra una importante superposición entre las rocas pertenecientes al magmatismo Choiyoi y los sedimentos acumulados en las cuencas carboníferas, entre los que son comunes los depósitos parálicos y continentales con intercalaciones de capas de carbón. Asimismo, estos depósitos del Paleozoico superior se acumularon sobre un espeso sustrato de carbonatos cambro-ordovícicos y de sedimentitas terrígenas ordovícicas a devónicas en cuya constitución participan importantes espesores de lutitas y turbiditas ricas en materia orgánica. Mientras que el volcanismo emitió importantes volúmenes de dióxido de carbono a la atmósfera pérmica, el calentamiento de las lutitas organógenas, carbones y carbonatos paleozoicos por el magma en ascenso produjo la generación de CO2 y CH4 cuya expulsión a la atmósfera se considera de importancia como para amplificar el cambio climático. El análisis del registro prácticamente continuo de capas rojas pérmicas en la Cuenca de Paganzo, donde el magmatismo Choiyoi no está presente, permite reconocer dos pulsos de fuerte desecación ambiental, uno Cisuraliano y otro a finales del Pérmico. Estas dos graves crisis climáticas son atribuidas a máximos de emisión de CO2 y CH4 a la atmósfera. El consecuente calentamiento y sus efectos colaterales, tales como lluvias ácidas, empobrecimiento de los suelos e incremento en la frecuencia de incendios forestales, fueron los responsables de la drástica declinación de la biodiversidad en el sudoeste de Gondwana y causaron la extinción de la mayor parte de la flora de Glossopteridales.Centro de Investigaciones GeológicasFacultad de Ciencias Naturales y Muse
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El magmatismo Choiyoi en el sudoeste de Gondwana: Su implicancia en la extinción en masa del Pérmico tardío-una revisión
'Pontificia Universidad Catolica de Valparaiso', 2017Co-Authors: Spalletti, Luis Antonio, Limarino, Carlos OscarAbstract:The end of the Permian period is marked by global warming and the biggest known mass extinction on Earth. The crisis is commonly attributed to the formation of large igneous provinces because continental volcanic emissions have the potential to control atmospheric carbon dioxide (CO2) levels and climate change. We propose that in southwestern Gondwana the long-term hothouse Permian environmental conditions were associated with the development of the Choiyoi magmatism. This large igneous province was developed between the Cisuralian and the early Triassic. It covers an area estimated at 1,680,000 km2 with an average thickness of 700 m, so that the volume of effusive and consanguineous rocks is estimated at 1,260,000 km3. Towards the western sector of the study region, a major overlap exists between the regional development of the Choiyoi magmatism and the Carboniferous sedimentary basins, which include paralic and continental deposits with intercalations of peat and coal beds. Commonly, these upper Palaeozoic deposits accumulated on a thick substrate composed of Cambro-Ordovician carbonates and Ordovician to Devonian terrigenous sedimentary rocks characterised by a large proportion of dark organic-rich shales and turbidite successions. While extensive volcanism released large masses of carbon dioxide into the Permian atmosphere, the heating of Palaeozoic organic-rich shales, peat and carbonates by ascending magma led to CO2 and CH4 gas generation in sufficient volumes to amplify the major climatic change. The analysis of the almost continuous record of Permian redbeds in the Paganzo basin, where the Choiyoi magmatism is not recorded, allowed us to recognize two main pulses of strong environmental desiccation, one at the Cisuralian and the second around the end-Permian. These two drastic climatic crisis are attributed to peaks of CO2 and CH4 outbursts to the atmosphere and related collateral effects, such as acid rain, impoverishment of soils and increase in forest-fire frequency. We propose that the combination of these multiple mechanisms triggered the decline of biodiversity in southwestern Gondwana and caused the end-Permian extinction of most of the Glossopteridales.El final del Pérmico está caracterizado por un proceso de calentamiento global que llevó a la mayor extinción en masa registrada en la Tierra. Esta crisis se atribuye comúnmente a la generación de grandes provincias ígneas en ámbito continental, cuyas emisiones volcánicas han controlado los niveles de CO2 en la atmósfera y el consecuente cambio climático. En este trabajo se propone que las condiciones fuertemente cálidas (hothouse) del Pérmico en el sudoeste de Gondwana estuvieron asociadas con el desarrollo del magmatismo Choiyoi. Esta provincia ígnea, que se desarrolló durante el lapso Cisuraliano-Triásico temprano, cubrió un área estimada en 1.680.000 km2 con un espesor medio de 700 m, de modo que los volúmenes de rocas efusivas y consanguíneas se estiman en alrededor de 1.260.000 km3 . Hacia el sector occidental de la región de estudio, se registra una importante superposición entre las rocas pertenecientes al magmatismo Choiyoi y los sedimentos acumulados en las cuencas carboníferas, entre los que son comunes los depósitos parálicos y continentales con intercalaciones de capas de carbón. Asimismo, estos depósitos del Paleozoico superior se acumularon sobre un espeso sustrato de carbonatos cambro-ordovícicos y de sedimentitas terrígenas ordovícicas a devónicas en cuya constitución participan importantes espesores de lutitas y turbiditas ricas en materia orgánica. Mientras que el volcanismo emitió importantes volúmenes de dióxido de carbono a la atmósfera pérmica, el calentamiento de las lutitas organógenas, carbones y carbonatos paleozoicos por el magma en ascenso produjo la generación de CO2 y CH4 cuya expulsión a la atmósfera se considera de importancia como para amplificar el cambio climático. El análisis del registro prácticamente continuo de capas rojas pérmicas en la Cuenca de Paganzo, donde el magmatismo Choiyoi no está presente, permite reconocer dos pulsos de fuerte desecación ambiental, uno Cisuraliano y otro a finales del Pérmico. Estas dos graves crisis climáticas son atribuidas a máximos de emisión de CO2 y CH4 a la atmósfera. El consecuente calentamiento y sus efectos colaterales, tales como lluvias ácidas, empobrecimiento de los suelos e incremento en la frecuencia de incendios forestales, fueron los responsables de la drástica declinación de la biodiversidad en el sudoeste de Gondwana y causaron la extinción de la mayor parte de la flora de Glossopteridales.Fil: Spalletti, Luis Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Limarino, Carlos Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; Argentin
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La secuencia Neopaleozoica de la quebrada de Agua de Jagüel (Precordillera de Mendoza): edad y redefinición estratigráfica
Asociación Geológica Argentina, 2016Co-Authors: Limarino, Carlos Oscar, Isbell, John L., Ciccioli, Patricia Lucia, Taboada, Arturo CesarAbstract:Se propone la denominación de Formación Cordón de Jagüel para la sucesión pérmica de areniscas, pelitas y escasos conglomerados que forman la ladera occidental del Cordón de Agua de Jagüel en la Precordillera de Mendoza. Estas rocas descansan en discordancia sobre metasedimentitas de la Formación Villavicencio y son separadas por falla de areniscas, pelitas y diamictitas pertenecientes a la Formación Agua de Jagüel (Pennsylvaniano). En la Formación Cordón de Jagüel se han identificado seis asociaciones de facies sedimentarias. La asociación 1 está integrada mayormente por conglomerados polimícticos y areniscas gruesas de origen fluvial. El inicio de un ascenso relativo del nivel del mar aparece registrado en la asociación de facies 2, formada por areniscas y pelitas carbonosas depositadas en ambientes transicionales, probablemente estuarinos. La asociación de facies 3, compuesta por areniscas finas, indica el pasaje a un ambiente marino costero, mientras que la asociación de facies 4 incluye areniscas con paquetes de estratificación entrecruzada de gran escala y probablemente corresponde a ambientes subtidales con importante crecimiento de barras de arena de gran porte. Una progresiva somerización llevó a la depositación de pelitas carbonosas, areniscas finas e intercalaciones de margas (asociación de facies 5) en ambientes restringidos (albuferas). Finalmente, la asociación de facies 6 (pelitas laminadas y areniscas finas) indica un nuevo evento transgresivo. Restos de invertebrados marinos pertenecientes a la Biozona de Costatumulus y de palinofloras conteniendo Lueckisporites virkkiae Potonié y Klaus sugieren una edad pérmica temprana, probablemente Cisuraliana tardía para la unidad.The neopaleozoic sequence of the Agua de Jagüel Creek (Precordillera de Mendoza): age and stratigraphic redefinition. The name of the Cordón de Jagüel Formation is proposed for Permian sandstones, mudstones and scarce conglomerates that form the western slope of the Cordón de Agua de Jagüel range in the Precordillera (Mendoza Province). These rocks unconformably overlie low-grade metamorphic rocks belonging to the Villavicencio Formation and are separated by a fault from sandstones, mudstones and diamictites of the Agua de Jagüel Formation (Pennsylvanian). Six facies association have been recognized in the Cordón de Jagüel Formation. The association 1 is composed of conglomerates and coarse-grained sandstones deposited in fluvial environment. The onset of a sea-level rise is recorded in the facies association 2, which is formed by sandstones and carbonaceous mudstones sedimented in transitional environments (estuarine?). Facies association 3 is made up by fine-grained sandstones indicating the transition to coastal marine settings while facies association 4, formed by large-scale cross-bedded sandstones, was very probably deposited in subtidal coastal environments. A progressive shallowing appears in the carbonaceous mudstones, fine-grained sandstones and marls forming the facies association 5 deposited in a transitional environment (lagoons). Finally, facies association 6 (shales and fine-grained sandstones) indicates a new sea level rise. Remains of the marine invertebrates belonging to the Costatumulus Biozone and palynofloras containing Lueckisporites virkkiae Potonié and Klaus suggest an early Permian age, probably late Cisuralian, for the unit.litic layer. Proximal non-amalgamated storm deposits are represented by thick sandy beds with hummocky cross stratification, bioclastic accumulations and ripples at the top intercalated with thin shaly levels. Distal storm deposits are thinly laminated o massive silty to sandy beds intercalated in shaly intervals.Fil: Limarino, Carlos Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Isbell, John L.. University of Wisconsin. Department of Geosciences; Estados UnidosFil: Ciccioli, Patricia Lucia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Taboada, Arturo Cesar. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Laboratorio de Investigaciones en Evolución y Biodiversidad; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
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A paleoclimatic review of southern South America during the late Paleozoic: a record from icehouse to extreme greenhouse conditions
'Elsevier BV', 2013Co-Authors: Limarino, Carlos Oscar, Spalletti, Luis Antonio, Cesari, Silvia Nelida, Taboada, Arturo Cesar, Isbell, John L., Geuna, Silvana Evangelina, Gulbranson, Erik L.Abstract:This paper proposes a review of the Late Mississippian to Permian paleoclimatic history for southern South America based on lithologic indicators, biostratigraphic information, and chronostratigraphic data. The region is divided into three major types of basins: 1. Eastern intraplate basins (e.g., Paraná Basin), 2.Western retroarc basins (e.g., Paganzo Basin) and 3.Western arc-related basins (e.g., Río Blanco Basin). Fourmajor types of paleo-climatic stages are recognized in these basins: 1. glacial (late Visean-early Bashkirian), 2. terminal glacial (Bashkirian-earliest Cisuralian) 3. postglacial (Cisuralian-early Guadalupian), and 4. semiarid-arid (late Guadalupian-Lopingian). The glacial stage began in the late Visean and continued until the latest Serpukhovian or early Bashkirian in almost all of the basins in southern South America. During the Bashkirian-earliest Cisuralian (terminal glacial stage), glacial deposits disappeared almost completely in the western retroarc basins (e.g., Paganzo Basin) but glaciation persisted in the eastern basins (e.g., Paraná and Sauce Grande Basins). A gradual climatic amelioration (postglacial stage) began to occur during the earliest Permian when glacial deposits completely disappeared across all of South America. During this interval, glacial diamictites were replaced by thick coal beds in the Paraná Basin while north-south climatic belts began to be delineated in the western basins, which were likely controlled by the distribution of mountain belts along the Panthalassan Margin of South America. Towards the late Permian, climatic belts became less evident and semiarid or arid conditions dominated in the southern South America basins. Eolian dunes, playa lake deposits, and mixed eolian-fluvial sequences occur in the Paraná Basin and in the western retroarc basins. Volcanism and volcaniclastic sedimentation dominated along the western margin of South America at that time. The stratigraphic record obtained in southern South America supports a long duration transition from icehouse to extreme greenhouse conditions.Fil: Limarino, Carlos Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Basicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Basicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Cesari, Silvia Nelida. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; ArgentinaFil: Spalletti, Luis Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Taboada, Arturo Cesar. Universidad Nacional de la Patagonia ; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Isbell, John L.. University of Wisconsin; Estados UnidosFil: Geuna, Silvana Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Basicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Basicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Gulbranson, Erik L.. University of Wisconsin; Estados Unidos. University of California; Estados Unido
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Paleogeography of the upper Paleozoic basins of southern South America: An overview
'Elsevier BV', 2006Co-Authors: Limarino, Carlos Oscar, Spalletti, Luis AntonioAbstract:The paleogeographic evolution of Late Paleozoic basins located in southern South America is addressed. Three major types of basins are recognized: infracratonic or intraplate, arc-related, and retroarc. Intraplate basins (i.e., Paraná, Chaco-Paraná, Sauce Grande-Colorado, and La Golondrina) are floored by continental or quasi-continental crust, with low or moderate subsidence rates and limited magmatic and tectonic activity. Arc-related basins (northern and central Chile, Navidad-Arizaro, Río Blanco, and Calingasta-Uspallata basins and depocenters along Chilean Patagonia) show a very complex tectonic history, widespread magmatic activity, high subsidence rates, and in some cases metamorphism of Late Paleozoic sediments. An intermediate situation corresponds to the retroarc basins (eastern Madre de Dios, Tarija, Paganzo, and Tepuel-Genoa), which lack extensive magmatism and metamorphism but in which coeval tectonism and sedimentation rates were likely more important than those in the intraplate region. According to the stratigraphic distribution of Late Paleozoic sediments, regional-scale discontinuities, and sedimentation pattern changes, five major paleogeographic stages are proposed. The lowermost is restricted to the proto-Pacific and retroarc basins, corresponds to the Mississippian (stage 1), and is characterized by shallow marine and transitional siliciclastic sediments. During stage 2 (Early Pennsylvanian), glacial-postglacial sequences dominated the infracratonic (or intraplate) and retroarc basins, and terrigenous shallow marine sediments prevailed in arc-related basins. Stage 3 (Late Pennsylvanian-Early Cisuralian) shows the maximum extension of glacial-postglacial sediments in the Paraná and Sauce Grande-Colorado basins (intraplate region), whereas fluvial deposits interfingering with thin intervals of shallow marine sediments prevailed in the retroarc basins. To the west, arc-related basins were dominated by coastal to deep marine conditions (including turbiditic successions). In the Late Cisuralian (stage 4), important differences in sedimentation patterns are registered for the western arc-related basins and eastern intraplate basins. The former were locally dominated by volcaniclastic sediments or marine deposits, and the intraplate basins are characterized by shallow marine conditions punctuated by several episodes of deltaic progradation. Finally, in the Late Permian (stage 5), volcanism and volcaniclastic sedimentation dominated in basins located along the western South American margin. The intraplate basins in turn were characterized by T-R cycles composed of shallow marine, deltaic, and fluvial siliciclastic deposits. © 2006 Elsevier Ltd. All rights reserved.Fil: Limarino, Carlos Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Spalletti, Luis Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; Argentin
Joerg W Schneider - One of the best experts on this subject based on the ideXlab platform.
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late paleozoic early mesozoic continental biostratigraphy links to the standard global chronostratigraphic scale
Palaeoworld, 2020Co-Authors: Lorenzo Marchetti, Frank Scholze, Spencer G. Lucas, Hendrik Klein, Joerg W Schneider, Sebastian Voigt, Stanislav Oplustil, Ralf Werneburg, V. K. GolubevAbstract:Abstract Nonmarine biostratigraphic/biochronologic schemes have been created for all or parts of the late Carboniferous–Middle Triassic using palynomorphs, megafossil plants, conchostracans, blattoid insects, tetrapod footprints and tetrapod body fossils, and these provide varied temporal resolution. Cross correlation of the nonmarine biochronologies to the Standard Global Chronostratigraphic Scale has been achieved in some parts of the late Carboniferous–Middle Triassic in locations where nonmarine and marine strata are intercalated, the nonmarine strata produce biochronologically significant fossils and the marine strata yield fusulinids, conodonts and/or ammonoids. Other cross correlations have been aided by magnetostratigraphy, chemostratigraphy and a growing database of radioisotopic ages. A synthetic nonmarine biochronology for the late Carboniferous–Middle Triassic based on all available nonmarine index fossils, integrated with the Standard Global Chronostratigraphic Scale, is presented here. The focus is on the nonmarine biostratigraphy/biochronology of blattoid insects, conchostracans, branchiosaurid amphibians, tetrapod footprints and tetrapod body fossils within the biochronological framework of land-vertebrate faunachrons. Correlation to the Standard Global Chronostratigraphic Scale presented here is divided into seven time intervals: Pennsylvanian, Carboniferous–Permian boundary, Cisuralian, Guadalupian, Lopingian, Permian–Triassic boundary and Early to Middle Triassic. The insects, conchostracans and branchiosaurs provide robust nonmarine correlations in the Pennsylvanian–Cisuralian, and the footprints and tetrapod body fossils provide robust correlations of varied precision within the entire Pennsylvanian–Middle Triassic. Radioisotopic ages are currently the strongest basis for cross correlation of the nonmarine biostratigraphy/biochronology to the Standard Global Chronostratigraphic Scale, particularly for the Pennsylvanian–Cisuralian. Chemostratigraphy and magnetostratigraphy thus far provide only limited links of nomarine and marine chronologies. Improvements in the nonmarine-marine correlations of late Paleozoic–Triassic Pangea require better alpha taxonomy and stratigraphic precision for the nonmarine fossil record integrated with more reliable radioisotopic ages and more extensive chemostratigraphic and magnetostratigraphic datasets.
Valéria Gallo - One of the best experts on this subject based on the ideXlab platform.
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Cranial anatomy of the predatory actinopterygian Brazilichthys macrognathus from the Permian (Cisuralian) Pedra de Fogo Formation, Parnaíba Basin, Brazil
Journal of Vertebrate Paleontology, 2019Co-Authors: Rodrigo T. Figueroa, Matt Friedman, Valéria GalloAbstract:Brazilichthys macrognathus is the only named actinopterygian from the Permian (Cisuralian) Pedra de Fogo Formation of northeastern Brazil, in which it is represented by a single three-dimensionally...
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Cranial anatomy of the predatory actinopterygian Brazilichthys macrognathus from the Permian (Cisuralian) Pedra de Fogo Formation, Parnaiba Basin, Brazil
2019Co-Authors: Rodrigo T. Figueroa, Matt Friedman, Valéria GalloAbstract:ABSTRACT Brazilichthys macrognathus is the only named actinopterygian from the Permain (Cisuralian) Pedra de Fogo Formation of northeastern Brazil, where it is represented by a single three-dimensionally preserved but incompletely described skull of unclear systematic placement. We used X-ray computed microtomography (μ-CT) to better document its anatomy and phylogenetic affinities. μ-CT reveals parts of the internal skeleton. We correct errors in original description, including the number of infraorbital bones and the misidentification of the dermosphenotic as sclerotic ossifications. These reinterpretations of external anatomy are joined by new data on internal structure, including the palate, parasphenoid, and branchial and hyoid arches. A maximum parsimony analysis of anatomical data resolves Brazilichthys as a stem actinopterygian, crownward of all Devonian species. This placement is supported by the absence of a dermosphenotic posterior ramus and the presence of opercular process of the hyomandibula. A similar placement is suggested by a Bayesian analysis of this same dataset, although relationships throughout the tree are less resolved. Our results reject previous interpretations of Brazilichthys as a relative of Birgeriidae, a Triassic group consistently placed within the actinopterygian crown. Although Acrolepis is too poorly known to be included in our analysis, we also reject a close relationship between this taxon and Brazilichthys, as their only shared similarities appear to be broadly distributed among early actinopterygians.
Spalletti, Luis Antonio - One of the best experts on this subject based on the ideXlab platform.
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El magmatismo Choiyoi en el sudoeste de Gondwana: Su implicancia en la extinción en masa del Pérmico tardío - una revisión
2019Co-Authors: Spalletti, Luis Antonio, Limarino, Carlos OscarAbstract:The end of the Permian period is marked by global warming and the biggest known mass extinction on Earth. The crisis is commonly attributed to the formation of large igneous provinces because continental volcanic emissions have the potential to control atmospheric carbon dioxide (CO2) levels and climate change. We propose that in southwestern Gondwana the long-term hothouse Permian environmental conditions were associated with the development of the Choiyoi magmatism. This large igneous province was developed between the Cisuralian and the early Triassic. It covers an area estimated at 1,680,000 km2 with an average thickness of 700 m, so that the volume of effusive and consanguineous rocks is estimated at 1,260,000 km3. Towards the western sector of the study region, a major overlap exists between the regional development of the Choiyoi magmatism and the Carboniferous sedimentary basins, which include paralic and continental deposits with intercalations of peat and coal beds. Commonly, these upper Palaeozoic deposits accumulated on a thick substrate composed of Cambro-Ordovician carbonates and Ordovician to Devonian terrigenous sedimentary rocks characterised by a large proportion of dark organic-rich shales and turbidite successions. While extensive volcanism released large masses of carbon dioxide into the Permian atmosphere, the heating of Palaeozoic organic-rich shales, peat and carbonates by ascending magma led to CO2 and CH4 gas generation in sufficient volumes to amplify the major climatic change. The analysis of the almost continuous record of Permian redbeds in the Paganzo basin, where the Choiyoi magmatism is not recorded, allowed us to recognize two main pulses of strong environmental desiccation, one at the Cisuralian and the second around the end-Permian. These two drastic climatic crisis are attributed to peaks of CO2 and CH4 outbursts to the atmosphere and related collateral effects, such as acid rain, impoverishment of soils and increase in forest-fire frequency. We propose that the combination of these multiple mechanisms triggered the decline of biodiversity in southwestern Gondwana and caused the end-Permian extinction of most of the Glossopteridales.El final del Pérmico está caracterizado por un proceso de calentamiento global que llevó a la mayor extinción en masa registrada en la Tierra. Esta crisis se atribuye comúnmente a la generación de grandes provincias ígneas en ámbito continental, cuyas emisiones volcánicas han controlado los niveles de CO2 en la atmósfera y el consecuente cambio climático. En este trabajo se propone que las condiciones fuertemente cálidas (hothouse) del Pérmico en el sudoeste de Gondwana estuvieron asociadas con el desarrollo del magmatismo Choiyoi. Esta provincia ígnea, que se desarrolló durante el lapso Cisuraliano-Triásico temprano, cubrió un área estimada en 1.680.000 km2 con un espesor medio de 700 m, de modo que los volúmenes de rocas efusivas y consanguíneas se estiman en alrededor de 1.260.000 km3. Hacia el sector occidental de la región de estudio, se registra una importante superposición entre las rocas pertenecientes al magmatismo Choiyoi y los sedimentos acumulados en las cuencas carboníferas, entre los que son comunes los depósitos parálicos y continentales con intercalaciones de capas de carbón. Asimismo, estos depósitos del Paleozoico superior se acumularon sobre un espeso sustrato de carbonatos cambro-ordovícicos y de sedimentitas terrígenas ordovícicas a devónicas en cuya constitución participan importantes espesores de lutitas y turbiditas ricas en materia orgánica. Mientras que el volcanismo emitió importantes volúmenes de dióxido de carbono a la atmósfera pérmica, el calentamiento de las lutitas organógenas, carbones y carbonatos paleozoicos por el magma en ascenso produjo la generación de CO2 y CH4 cuya expulsión a la atmósfera se considera de importancia como para amplificar el cambio climático. El análisis del registro prácticamente continuo de capas rojas pérmicas en la Cuenca de Paganzo, donde el magmatismo Choiyoi no está presente, permite reconocer dos pulsos de fuerte desecación ambiental, uno Cisuraliano y otro a finales del Pérmico. Estas dos graves crisis climáticas son atribuidas a máximos de emisión de CO2 y CH4 a la atmósfera. El consecuente calentamiento y sus efectos colaterales, tales como lluvias ácidas, empobrecimiento de los suelos e incremento en la frecuencia de incendios forestales, fueron los responsables de la drástica declinación de la biodiversidad en el sudoeste de Gondwana y causaron la extinción de la mayor parte de la flora de Glossopteridales.Centro de Investigaciones GeológicasFacultad de Ciencias Naturales y Muse
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El magmatismo Choiyoi en el sudoeste de Gondwana: Su implicancia en la extinción en masa del Pérmico tardío-una revisión
'Pontificia Universidad Catolica de Valparaiso', 2017Co-Authors: Spalletti, Luis Antonio, Limarino, Carlos OscarAbstract:The end of the Permian period is marked by global warming and the biggest known mass extinction on Earth. The crisis is commonly attributed to the formation of large igneous provinces because continental volcanic emissions have the potential to control atmospheric carbon dioxide (CO2) levels and climate change. We propose that in southwestern Gondwana the long-term hothouse Permian environmental conditions were associated with the development of the Choiyoi magmatism. This large igneous province was developed between the Cisuralian and the early Triassic. It covers an area estimated at 1,680,000 km2 with an average thickness of 700 m, so that the volume of effusive and consanguineous rocks is estimated at 1,260,000 km3. Towards the western sector of the study region, a major overlap exists between the regional development of the Choiyoi magmatism and the Carboniferous sedimentary basins, which include paralic and continental deposits with intercalations of peat and coal beds. Commonly, these upper Palaeozoic deposits accumulated on a thick substrate composed of Cambro-Ordovician carbonates and Ordovician to Devonian terrigenous sedimentary rocks characterised by a large proportion of dark organic-rich shales and turbidite successions. While extensive volcanism released large masses of carbon dioxide into the Permian atmosphere, the heating of Palaeozoic organic-rich shales, peat and carbonates by ascending magma led to CO2 and CH4 gas generation in sufficient volumes to amplify the major climatic change. The analysis of the almost continuous record of Permian redbeds in the Paganzo basin, where the Choiyoi magmatism is not recorded, allowed us to recognize two main pulses of strong environmental desiccation, one at the Cisuralian and the second around the end-Permian. These two drastic climatic crisis are attributed to peaks of CO2 and CH4 outbursts to the atmosphere and related collateral effects, such as acid rain, impoverishment of soils and increase in forest-fire frequency. We propose that the combination of these multiple mechanisms triggered the decline of biodiversity in southwestern Gondwana and caused the end-Permian extinction of most of the Glossopteridales.El final del Pérmico está caracterizado por un proceso de calentamiento global que llevó a la mayor extinción en masa registrada en la Tierra. Esta crisis se atribuye comúnmente a la generación de grandes provincias ígneas en ámbito continental, cuyas emisiones volcánicas han controlado los niveles de CO2 en la atmósfera y el consecuente cambio climático. En este trabajo se propone que las condiciones fuertemente cálidas (hothouse) del Pérmico en el sudoeste de Gondwana estuvieron asociadas con el desarrollo del magmatismo Choiyoi. Esta provincia ígnea, que se desarrolló durante el lapso Cisuraliano-Triásico temprano, cubrió un área estimada en 1.680.000 km2 con un espesor medio de 700 m, de modo que los volúmenes de rocas efusivas y consanguíneas se estiman en alrededor de 1.260.000 km3 . Hacia el sector occidental de la región de estudio, se registra una importante superposición entre las rocas pertenecientes al magmatismo Choiyoi y los sedimentos acumulados en las cuencas carboníferas, entre los que son comunes los depósitos parálicos y continentales con intercalaciones de capas de carbón. Asimismo, estos depósitos del Paleozoico superior se acumularon sobre un espeso sustrato de carbonatos cambro-ordovícicos y de sedimentitas terrígenas ordovícicas a devónicas en cuya constitución participan importantes espesores de lutitas y turbiditas ricas en materia orgánica. Mientras que el volcanismo emitió importantes volúmenes de dióxido de carbono a la atmósfera pérmica, el calentamiento de las lutitas organógenas, carbones y carbonatos paleozoicos por el magma en ascenso produjo la generación de CO2 y CH4 cuya expulsión a la atmósfera se considera de importancia como para amplificar el cambio climático. El análisis del registro prácticamente continuo de capas rojas pérmicas en la Cuenca de Paganzo, donde el magmatismo Choiyoi no está presente, permite reconocer dos pulsos de fuerte desecación ambiental, uno Cisuraliano y otro a finales del Pérmico. Estas dos graves crisis climáticas son atribuidas a máximos de emisión de CO2 y CH4 a la atmósfera. El consecuente calentamiento y sus efectos colaterales, tales como lluvias ácidas, empobrecimiento de los suelos e incremento en la frecuencia de incendios forestales, fueron los responsables de la drástica declinación de la biodiversidad en el sudoeste de Gondwana y causaron la extinción de la mayor parte de la flora de Glossopteridales.Fil: Spalletti, Luis Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Limarino, Carlos Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; Argentin
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A paleoclimatic review of southern South America during the late Paleozoic: a record from icehouse to extreme greenhouse conditions
'Elsevier BV', 2013Co-Authors: Limarino, Carlos Oscar, Spalletti, Luis Antonio, Cesari, Silvia Nelida, Taboada, Arturo Cesar, Isbell, John L., Geuna, Silvana Evangelina, Gulbranson, Erik L.Abstract:This paper proposes a review of the Late Mississippian to Permian paleoclimatic history for southern South America based on lithologic indicators, biostratigraphic information, and chronostratigraphic data. The region is divided into three major types of basins: 1. Eastern intraplate basins (e.g., Paraná Basin), 2.Western retroarc basins (e.g., Paganzo Basin) and 3.Western arc-related basins (e.g., Río Blanco Basin). Fourmajor types of paleo-climatic stages are recognized in these basins: 1. glacial (late Visean-early Bashkirian), 2. terminal glacial (Bashkirian-earliest Cisuralian) 3. postglacial (Cisuralian-early Guadalupian), and 4. semiarid-arid (late Guadalupian-Lopingian). The glacial stage began in the late Visean and continued until the latest Serpukhovian or early Bashkirian in almost all of the basins in southern South America. During the Bashkirian-earliest Cisuralian (terminal glacial stage), glacial deposits disappeared almost completely in the western retroarc basins (e.g., Paganzo Basin) but glaciation persisted in the eastern basins (e.g., Paraná and Sauce Grande Basins). A gradual climatic amelioration (postglacial stage) began to occur during the earliest Permian when glacial deposits completely disappeared across all of South America. During this interval, glacial diamictites were replaced by thick coal beds in the Paraná Basin while north-south climatic belts began to be delineated in the western basins, which were likely controlled by the distribution of mountain belts along the Panthalassan Margin of South America. Towards the late Permian, climatic belts became less evident and semiarid or arid conditions dominated in the southern South America basins. Eolian dunes, playa lake deposits, and mixed eolian-fluvial sequences occur in the Paraná Basin and in the western retroarc basins. Volcanism and volcaniclastic sedimentation dominated along the western margin of South America at that time. The stratigraphic record obtained in southern South America supports a long duration transition from icehouse to extreme greenhouse conditions.Fil: Limarino, Carlos Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Basicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Basicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Cesari, Silvia Nelida. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; ArgentinaFil: Spalletti, Luis Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Taboada, Arturo Cesar. Universidad Nacional de la Patagonia ; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Isbell, John L.. University of Wisconsin; Estados UnidosFil: Geuna, Silvana Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Basicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Basicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Gulbranson, Erik L.. University of Wisconsin; Estados Unidos. University of California; Estados Unido
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Paleogeography of the upper Paleozoic basins of southern South America: An overview
'Elsevier BV', 2006Co-Authors: Limarino, Carlos Oscar, Spalletti, Luis AntonioAbstract:The paleogeographic evolution of Late Paleozoic basins located in southern South America is addressed. Three major types of basins are recognized: infracratonic or intraplate, arc-related, and retroarc. Intraplate basins (i.e., Paraná, Chaco-Paraná, Sauce Grande-Colorado, and La Golondrina) are floored by continental or quasi-continental crust, with low or moderate subsidence rates and limited magmatic and tectonic activity. Arc-related basins (northern and central Chile, Navidad-Arizaro, Río Blanco, and Calingasta-Uspallata basins and depocenters along Chilean Patagonia) show a very complex tectonic history, widespread magmatic activity, high subsidence rates, and in some cases metamorphism of Late Paleozoic sediments. An intermediate situation corresponds to the retroarc basins (eastern Madre de Dios, Tarija, Paganzo, and Tepuel-Genoa), which lack extensive magmatism and metamorphism but in which coeval tectonism and sedimentation rates were likely more important than those in the intraplate region. According to the stratigraphic distribution of Late Paleozoic sediments, regional-scale discontinuities, and sedimentation pattern changes, five major paleogeographic stages are proposed. The lowermost is restricted to the proto-Pacific and retroarc basins, corresponds to the Mississippian (stage 1), and is characterized by shallow marine and transitional siliciclastic sediments. During stage 2 (Early Pennsylvanian), glacial-postglacial sequences dominated the infracratonic (or intraplate) and retroarc basins, and terrigenous shallow marine sediments prevailed in arc-related basins. Stage 3 (Late Pennsylvanian-Early Cisuralian) shows the maximum extension of glacial-postglacial sediments in the Paraná and Sauce Grande-Colorado basins (intraplate region), whereas fluvial deposits interfingering with thin intervals of shallow marine sediments prevailed in the retroarc basins. To the west, arc-related basins were dominated by coastal to deep marine conditions (including turbiditic successions). In the Late Cisuralian (stage 4), important differences in sedimentation patterns are registered for the western arc-related basins and eastern intraplate basins. The former were locally dominated by volcaniclastic sediments or marine deposits, and the intraplate basins are characterized by shallow marine conditions punctuated by several episodes of deltaic progradation. Finally, in the Late Permian (stage 5), volcanism and volcaniclastic sedimentation dominated in basins located along the western South American margin. The intraplate basins in turn were characterized by T-R cycles composed of shallow marine, deltaic, and fluvial siliciclastic deposits. © 2006 Elsevier Ltd. All rights reserved.Fil: Limarino, Carlos Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Spalletti, Luis Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; Argentin
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late paleozoic early mesozoic continental biostratigraphy links to the standard global chronostratigraphic scale
Palaeoworld, 2020Co-Authors: Lorenzo Marchetti, Frank Scholze, Spencer G. Lucas, Hendrik Klein, Joerg W Schneider, Sebastian Voigt, Stanislav Oplustil, Ralf Werneburg, V. K. GolubevAbstract:Abstract Nonmarine biostratigraphic/biochronologic schemes have been created for all or parts of the late Carboniferous–Middle Triassic using palynomorphs, megafossil plants, conchostracans, blattoid insects, tetrapod footprints and tetrapod body fossils, and these provide varied temporal resolution. Cross correlation of the nonmarine biochronologies to the Standard Global Chronostratigraphic Scale has been achieved in some parts of the late Carboniferous–Middle Triassic in locations where nonmarine and marine strata are intercalated, the nonmarine strata produce biochronologically significant fossils and the marine strata yield fusulinids, conodonts and/or ammonoids. Other cross correlations have been aided by magnetostratigraphy, chemostratigraphy and a growing database of radioisotopic ages. A synthetic nonmarine biochronology for the late Carboniferous–Middle Triassic based on all available nonmarine index fossils, integrated with the Standard Global Chronostratigraphic Scale, is presented here. The focus is on the nonmarine biostratigraphy/biochronology of blattoid insects, conchostracans, branchiosaurid amphibians, tetrapod footprints and tetrapod body fossils within the biochronological framework of land-vertebrate faunachrons. Correlation to the Standard Global Chronostratigraphic Scale presented here is divided into seven time intervals: Pennsylvanian, Carboniferous–Permian boundary, Cisuralian, Guadalupian, Lopingian, Permian–Triassic boundary and Early to Middle Triassic. The insects, conchostracans and branchiosaurs provide robust nonmarine correlations in the Pennsylvanian–Cisuralian, and the footprints and tetrapod body fossils provide robust correlations of varied precision within the entire Pennsylvanian–Middle Triassic. Radioisotopic ages are currently the strongest basis for cross correlation of the nonmarine biostratigraphy/biochronology to the Standard Global Chronostratigraphic Scale, particularly for the Pennsylvanian–Cisuralian. Chemostratigraphy and magnetostratigraphy thus far provide only limited links of nomarine and marine chronologies. Improvements in the nonmarine-marine correlations of late Paleozoic–Triassic Pangea require better alpha taxonomy and stratigraphic precision for the nonmarine fossil record integrated with more reliable radioisotopic ages and more extensive chemostratigraphic and magnetostratigraphic datasets.