Examinando por Autor "Cardona A."
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Ítem Comment on ‘Petrotectonic characteristics, geochemistry, and U–Pb geochronology of Jurassic plutons in the Upper Magdalena Valley-Colombia: Implications on the evolution of magmatic arcs in the NW Andes’ by Rodríguez et al. (2018)(PERGAMON-ELSEVIER SCIENCE LTD, 2019-11-01) Bustamante C.; Cardona A.; Bustamante A.; Vanegas J.; Bustamante C.; Cardona A.; Bustamante A.; Vanegas J.; Universidad EAFIT. Departamento de Ciencias; Geología Ambiental y Tectónica[No abstract available]Ítem The Paleogene arcs of the northern Andes of Colombia and Panama: Insights on plate kinematic implications from new and existing geochemical, geochronological and isotopic data(ELSEVIER SCIENCE BV, 2018-12-06) Cardona A.; León S.; Jaramillo J.S.; Montes C.; Valencia V.; Vanegas J.; Bustamante C.; Echeverri S.; Cardona A.; León S.; Jaramillo J.S.; Montes C.; Valencia V.; Vanegas J.; Bustamante C.; Echeverri S.; Universidad EAFIT. Departamento de Ciencias; Geología Ambiental y TectónicaThe northern Andes of Colombia comprise two non-cogenetic Paleogene arcs formed in contrasting geodynamic settings including continental and oceanic domains. New whole-rock geochemistry and isotopic constraints, together with a review of 332 geochemical, 76 isotopic and 204 geochronological data from Paleocene to Eocene volcanic and plutonic rocks exposed in central and western Colombia and Panama, are used to evaluate cause-effect relations between regional plate kinematics and the spatio-temporal distribution of the circum-Caribbean magmatic arcs. Short-lived, ~60–45 Ma arc-like magmatism in the Central Cordillera of Colombia was emplaced in a thickened continental crust due to the oblique subduction of the Caribbean oceanic plate underneath South America, as suggested by the high Sr/Y ratios. Conversely, the Panama Arc, and its poorly explored extension in the northwestern segment of the Western Cordillera of Colombia document a major phase of tholeiitic to calc-alkaline arc magmatism between ~71 Ma and ~34 Ma, mostly derived from a hydrated mantle wedge, and emplaced in an oceanic plateau crust. This arc record a major phase of magmatic activity between 40 Ma and 50 Ma that can be associated to changes in the convergence direction and subduction rates of the Farallon plate. Farther to the south, in the Pacific region of Colombia, Eocene arc-related rocks from the Timbiqui Complex show a geochemical signature that suggests a magmatic origin from melting of both a subduction-modified mantle and lower tectonically thickened crust. A possible interpretation for the Pacific and Western Colombia-Panama Arc systems, and its analogous in Ecuador, recall an Aleutian-type convergent margin in which the continental arc laterally switches to a purely oceanic system along the trailing edge of the Caribbean plate as consequence of eastward subduction of the Farallon plate. © 2018 Elsevier B.V.Ítem U-Pb Ages and Hf Isotopes in Zircons from Parautochthonous Mesozoic Terranes in the Western Margin of Pangea: Implications for the Terrane Configurations in the Northern Andes(UNIV CHICAGO PRESS, 2017-09-01) Bustamante C.; Archanjo C.J.; Cardona A.; Bustamante A.; Valencia V.A.; Bustamante C.; Archanjo C.J.; Cardona A.; Bustamante A.; Valencia V.A.; Universidad EAFIT. Departamento de Ciencias; Geología Ambiental y TectónicaU-Pb laser ablation inductively coupled plasma mass spectrometry ages and Hf isotopes in zircons were used to constrain the nature of two geological units representative of the basement of the Central Cordillera of Colombia. Graphite-quartz-muscovite schists from the Cajamarca Complex show inherited detrital zircons supplied mostly from Late Jurassic (ca. 167 Ma), Ediacaran (ca. 638 Ma), and Tonian (Grenvillian; ca. 1000 Ma) sources. These marine volcanosedimentary deposits form an N-trending metamorphic belt in fault contact to the east with orthogneisses and amphibolites of the Tierradentro unit. Zircon U-Pb determinations of the Tierradentro rockspreviously interpreted as Grenvillian basement slicesyielded crystallization ages between 271 and 234 Ma. Initial Hf data reveal that the Tierradentro unit shares isotopic characteristics similar to other Permo-Triassic rocks of the Central Cordillera. In contrast, inherited detrital zircons from the Jurassic metasedimentary rocks suggest that their sources are distinct from the plutonic rocks that crop out in the Central Cordillera with Jurassic crystallization ages. Large xenoliths of the Tierradentro unit within the Ibague batholith indicate that the granodioritic magma mostly intruded a Permo-Triassic basement possibly by exploiting the Otu-Pericos fault. The Jurassic metasedimentary belt is correlated further south with a similar sequence in the Ecuadorian Andes named Salado terrane.Ítem Unravelling the widening of the earliest Andean northern orogen: Maastrichtian to early Eocene intra-basinal deformation in the northern Eastern Cordillera of Colombia(Wiley-Blackwell Publishing Ltd, 2020-07-21) Bayona G.; Baquero M.; Ramírez C.; Tabares M.; Salazar A.M.; Nova G.; Duarte E.; Pardo A.; Plata A.; Jaramillo C.; Rodríguez G.; Caballero V.; Cardona A.; Montes C.; Gómez Marulanda S.; Cárdenas-Rozo A.L.; Universidad EAFIT. Departamento de Geología; Ciencias del MarThe onset of deformation in the northern Andes is overprinted by subsequent stages of basin deformation, complicating the examination of competing models illustrating potential location of earliest synorogenic basins and uplifts. To establish the width of the earliest northern Andean orogen, we carried out field mapping, palynological dating, sedimentary, stratigraphic and provenance analyses in Campanian to lower Eocene units exposed in the northern Eastern Cordillera of Colombia (Cocuy region) and compare the results with coeval succession in adjacent basins. The onset of deformation is recorded in earliest Maastrichtian time, as terrigenous detritus arrived into the basin marking the end of chemical precipitation and the onset of clastic deposition produced by the uplift of a western source area dominated by shaly Cretaceous rocks. Disconformable contacts within the upper Maastrichtian to middle Palaeocene succession document increasing supply of quartzose sandy detritus from Cretaceous quartzose rocks exposed in eastern source areas. The continued unroofing of both source areas produced a rapid shift in depositional environments from shallow marine in Maastrichtian to fluvial-lacustrine systems during the Palaeocene-early Eocene. Supply of immature Jurassic sandstones from nearby western uplifts, together with localized plutonic and volcanic Cretaceous rocks, caused a shift in Palaeocene sandstones composition from quartzarenites to litharenites. Supply of detrital sandy fragments, unstable heavy minerals and Cretaceous to Ordovician detrital zircons, were derived from nearby uplifted blocks and from SW fluvial systems within the synorogenic basin, instead of distal basement rocks. The presence of volcanic rock fragments and 51–59 Ma volcanic zircons constrain magmatism within the basin. The Maastrichtian–Palaeocene sequence studied here documents crustal deformation that correlates with coeval deformation farther south in Ecuador and Peru. Slab flattening of the subducting Caribbean plate produced a wider orogen (>400 km) with a continental magmatic arc and intra-basinal deformation and magmatism. © 2020 International Association of Sedimentologists and European Association of Geoscientists and Engineers and John Wiley - Sons LtdÍtem Unravelling the widening of the earliest Andean northern orogen: Maastrichtian to early Eocene intra-basinal deformation in the northern Eastern Cordillera of Colombia(Wiley-Blackwell Publishing Ltd, 2020-07-21) Bayona G.; Baquero M.; Ramírez C.; Tabares M.; Salazar A.M.; Nova G.; Duarte E.; Pardo A.; Plata A.; Jaramillo C.; Rodríguez G.; Caballero V.; Cardona A.; Montes C.; Gómez Marulanda S.; Cárdenas-Rozo A.L.; Universidad EAFIT. Departamento de Ciencias; Biodiversidad, Evolución y ConservaciónThe onset of deformation in the northern Andes is overprinted by subsequent stages of basin deformation, complicating the examination of competing models illustrating potential location of earliest synorogenic basins and uplifts. To establish the width of the earliest northern Andean orogen, we carried out field mapping, palynological dating, sedimentary, stratigraphic and provenance analyses in Campanian to lower Eocene units exposed in the northern Eastern Cordillera of Colombia (Cocuy region) and compare the results with coeval succession in adjacent basins. The onset of deformation is recorded in earliest Maastrichtian time, as terrigenous detritus arrived into the basin marking the end of chemical precipitation and the onset of clastic deposition produced by the uplift of a western source area dominated by shaly Cretaceous rocks. Disconformable contacts within the upper Maastrichtian to middle Palaeocene succession document increasing supply of quartzose sandy detritus from Cretaceous quartzose rocks exposed in eastern source areas. The continued unroofing of both source areas produced a rapid shift in depositional environments from shallow marine in Maastrichtian to fluvial-lacustrine systems during the Palaeocene-early Eocene. Supply of immature Jurassic sandstones from nearby western uplifts, together with localized plutonic and volcanic Cretaceous rocks, caused a shift in Palaeocene sandstones composition from quartzarenites to litharenites. Supply of detrital sandy fragments, unstable heavy minerals and Cretaceous to Ordovician detrital zircons, were derived from nearby uplifted blocks and from SW fluvial systems within the synorogenic basin, instead of distal basement rocks. The presence of volcanic rock fragments and 51–59 Ma volcanic zircons constrain magmatism within the basin. The Maastrichtian–Palaeocene sequence studied here documents crustal deformation that correlates with coeval deformation farther south in Ecuador and Peru. Slab flattening of the subducting Caribbean plate produced a wider orogen (>400 km) with a continental magmatic arc and intra-basinal deformation and magmatism. © 2020 International Association of Sedimentologists and European Association of Geoscientists and Engineers and John Wiley - Sons Ltd