Artículos

URI permanente para esta colección

https://hdl.handle.net/10784/27223

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Examinando Artículos por Autor "Cardona A."

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    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]
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    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 Tectónica
    The 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.
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    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 Tectónica
    U-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.