Depositional environment of the Quebradagrande complex : implications for the early to mid-Cretaceous tectono-magmatic evolution of the northern Andes

The sedimentary and volcano-sedimentary rocks of the Quebradagrande Complex on the northwestern margin of South America record the arc and its associated back-arc tectonic settings. Sixteen thin sections were analyzed revealing distinct lava facies from basic to intermediate compositions. Field rela...

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Autores:
Marín Jaramillo, Juan Pablo
Tipo de recurso:
Trabajo de grado de pregrado
Fecha de publicación:
2018
Institución:
Universidad de los Andes
Repositorio:
Séneca: repositorio Uniandes
Idioma:
eng
OAI Identifier:
oai:repositorio.uniandes.edu.co:1992/39325
Acceso en línea:
http://hdl.handle.net/1992/39325
Palabra clave:
Tectónica de placas
Rocas sedimentarias
Estratigrafía
Rocas ígneas
Magmatismo
Quebradagrande (Colombia)
Geociencias
Rights
openAccess
License
http://creativecommons.org/licenses/by-nc-sa/4.0/
Description
Summary:The sedimentary and volcano-sedimentary rocks of the Quebradagrande Complex on the northwestern margin of South America record the arc and its associated back-arc tectonic settings. Sixteen thin sections were analyzed revealing distinct lava facies from basic to intermediate compositions. Field relations, six stratigraphic sections and petrographic analysis allow the identification of three main lithofacies: Sedimentary, effusive and pyroclastic. Their spatial relation shows an east to west transition from deep ocean sediments, basic lava compositions and gravity flow pyroclastic deposits to shallower depositional environments, intermediate lava compositions and fall pyroclastic deposits. The results obtained in this study confirm the tectono-magmatic models previously proposed in which a para-autochthonous island arc along with a marginal basin were stablished for early to mid-Cretaceous ages