Examinando por Materia "Tectonics"

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    Detrital zircon fission-track thermochronology and magnetic fabric of the Amagá Formation (Colombia): Intracontinental deformation and exhumation events in the northwestern Andes
    (ELSEVIER SCIENCE BV, 2017-07-01) Piedrahita, V.A.; Bernet, M.; Chadima, M.; Sierra, G.M.; Marín-Cerón, M.I.; Toro, G.E.; Piedrahita, V.A.; Bernet, M.; Chadima, M.; Sierra, G.M.; Marín-Cerón, M.I.; Toro, G.E.; Universidad EAFIT. Departamento de Ciencias; Geología Ambiental y Tectónica
    New detrital zircon-fission track (ZFT) and magnetic fabric data are presented to constrain the time of deposition, provenance and deformation of the of Lower and Upper members of the Amagá Formation in the Amagá Basin. The Amagá Basin is located in the northern Andes, between the Western and Central Cordilleras of Colombia. The Amagá Formation was deposited in a transpressive geodynamic context and is allegedly synchronous with tectonic events such as the Andean orogeny and the Panama-Choco Block collision with the northwestern South American Plate. Detrital ZFT data confirm an Oligocene age for the Lower Member and a middle-Miocene age for the Upper Member of the Amagá Formation. In addition to constraining the depositional age, the ZFT data presented in this study also reflect Paleocene-Eocene, late to early Oligocene and late to middle Miocene cooling in sediment source areas mainly located in the Central and Western Cordilleras of Colombia. These ages can be associated with regional exhumation events in the central and northern Andes of South America. Collisional stages of the Panama-Choco Block against northwestern South America, subduction of the Farallon-Nazca Plate and strike-slip reactivation periods of the Cauca-Romeral fault system, caused NW-SE compression and NE-SW simple shear in the Amagá Basin. This deformational regime, identified by magnetic fabric data, induces syn- and post-depositional deformation over the Amagá Formation. © 2017 Elsevier B.V.
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    Kinematics and stress field analysis from a major strike-slip fault on the Northern Andes : the Palestina Fault System
    (Universidad EAFIT, 2020) Duque Trujillo, José Fernando; Saldarriaga Echeverri, Mónica; Duque Trujillo, José Fernando
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    Proceso de ASC - ESTUDIO DEL BASAMENTO PALEOZOICO DE LA CORDILLERA CENTRAL
    (Universidad EAFIT, 2023) Bustamante, Camilo; Universidad EAFIT
    Durante el período Permico, entre ~295 y 250 Ma, las masas continentales de la Tierra se fueron aglutinando para conformar lo que se conoce como el supercontinente Pangea. Este complejo proceso se dio a través de la colisión de los continentes, trayendo como consecuencia el cierre del océano Rheico, lo que marcó el fin de la era Paleozoica (~250 Ma). Su futura separaciónn se dio a finales del período Triásico (~200 Ma), dando origen a las cuencas oceánicas que se conocen actualmente, y a la reorganización de los continentes hasta alcanzar su forma y posición actual.Las reconstrucciones paleogeográficas sugieren que las partes externes de Pangea estaban conformadas por Norteamérica; Suramérica, la parte oriental de Antartica, Australia, y Nueva Guinea; conformando la cadena de montañas Terra Australis. Sin embargo, sus vestigios se han perdido gracias a la erosión y a la sobreimposición de los eventos orogénicos que han caracterizado la margen occidental de Pangea. Especificamente en Colombia, son escasos los registros de Pangea debido a la fuerte cobertura vegetal y al clima tropical, que ha alterado gran parte de este registro. Actualmente se han reconocido fragmentos de lo que sería considerado el registro de este supercontinente en la Sierra Nevada de Santa Marta, el Macizo de Santander y el norte de la Cordillera Central; aunque no se han discriminado en detalle ni se conoce con certeza su origen.Este proyecto busca entender y caracterizar con mayor precisión, los vestigios del supercontinente Pangea en Colombia, los cuales conforman la mayor parte del basamento de la Cordillera Central. Este proyecto continúa con la línea de proyectos de semillero que se vienen trabajando desde 2019, en los cuales se ha estudiado el metamorfismo y magmatismo de la Cordillera Central.
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    Regional controls in the distribution and morphometry of deep-water gravitational deposits along a convergent tectonic margin. Southern Caribbean of Colombia
    (Elsevier BV, 2020-08-06) Naranjo Vesga, Julián Francisco; Ortiz Karpf, Andrea; Wood, Lesli; Jobe, Z.; Paniagua, J.; Shumaker, L.; Mateus Tarazona, Darwin; Universidad EAFIT. Departamento de Geología; Ciencias del Mar
    Deep-water fold and thrust belts often develop in convergent tectonic margins, creating irregular slope profiles that control the distribution of deep-water gravity deposits. However, in areas with high sediment supply, the erosion and sedimentation can minimize structural relief and smooth the slope. Using multibeam bathymetry with 3D seismic data, we analyze the distribution of deep-water gravity-driven deposits along the convergent margin of the southern Caribbean of Colombia, comparing areas with different continental sediment supply, slope profile, and shelf width. We identify three geomorphological zones: The Northern, Central and Southern Zones. The Northern Zone is characterized by a gentle slope topography, high sediment supply, and large (>100 km length) channel-levee systems traversing the slope and basin floor. In this zone, shelf-attached mass-transport deposits erode and smooth sea-floor topography. The Central Zone is characterized by low sediment supply and steep and irregular slope topography. Here, short-runout mass-transport deposits sourced from the crests and steep flanks of emergent anticlines are common. The irregular relief created by tectonic deformation forms barriers for sediment transport, leading to tortuous sediment-flow pathways. Submarine canyons incise the thrust-cored anticlines, transporting sediment through interconnected, adjacent piggyback sub-basins. Finally, the Southern Zone is characterized by steep slope and moderate sediment supply. Here, tectonic deformation has been smoothed by numerous shelf-attached mass-transport deposits. The erosional scours carved by mass flows merge downslope and evolve into submarine canyons that can deliver mass-transport deposits more than 80 km into the basin. We analyze the impact of slope profile, sediment input and shelf width on the distribution and morphology of deep-water deposits along the southern Colombian Caribbean margin, and present a predictive model for the depositional patterns more likely to develop in other continental margins affected by deep-water fold and thrust belts. © 2020 Elsevier Ltd
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    Timing of rifting in the southern Gulf of California and its conjugate margins: Insights from the plutonic record
    (Geological Society of America, 2015-05-01) Duque-Trujillo, J.F.; Duque-Trujillo, J.F.; Universidad EAFIT. Departamento de Ciencias; Geología Ambiental y Tectónica
    The Gulf of California is a young example of crustal stretching and transtensional shearing leading to the birth of a new oceanic basin at a formerly convergent margin. Previous studies focused along the southwestern rifted margin in Baja California...