Evolución del arco volcánico Plioceno-Cuaternario a los 39°S, características geoquímicas y magnetismo
Cargando...
Archivos
Fecha
2021
Autores
Profesor/a Guía
Facultad/escuela
Idioma
es
Título de la revista
ISSN de la revista
Título del volumen
Editor
Universidad Andrés Bello
Nombre de Curso
Licencia CC
Licencia CC
Resumen
El presente estudio trata de reflejar las variaciones geoquímicas y composicionales que determinan la evolución arquitectónica del arco volcánico Plioceno-Cuaternario, en los distintos estadios de deformación que han ocurrido en el margen occidental de Sudamérica. La ZVSC, cubre entre las latitudes de los 38°-42°S, y este estudio se centra en a los 39°S zona que cubre la región de la Araucanía y los Ríos, en territorio chileno y los departamentos de Huilliches y Aluminé en la provincia de Neuquén, Argentina.
Para determinar las variaciones que han ocurrido en la zona se analiza e interpreta una recopilación integra de datos bibliográficos, en conjunto con datos inéditos de los 39°S 71°-70°W, y selección de gráficos geoquímicos de elementos mayores (TAS y AFM), elementos traza (La/Yb vs Distancia a la fosa; La/Nb vs La; Ba/La vs La/Sm; Ba/Ta vs La/Ta) y tierras raras (Diagrama Spider).
Los resultados obtenidos mediante elementos trazan tal como su distribución (La/Yb vs Distancia a la fosa), y afinidad arco-trasarco-intraplaca (Ba/Ta vs La/Ta y La/Nb vs La) demuestran que la actividad magmática a los 39°S fue mayor durante la transición Mioceno superior-Plioceno, con tasas de convergencia mayor a las actuales, generando un arco volcánico con un ancho mayor al actual.
La integración e interpretación de los datos geoquímicos, junto con la consideración de los factores que controlan la posición de arcos volcánicos, permiten generar un modelo evolutivo para la transecta 39°S.
The present study tries to reflect the geochemical and compositional variations that determine the architectural evolution of the Pliocene-Quaternary volcanic arc, in the different stages of deformation that have occurred in the western margin of South America. The ZVSC covers between the latitudes of 38 ° -42 ° S, and this study focuses on the 39 ° S area that covers the Araucanía and Los Ríos region, in Chilean territory and the departments of Huilliches and Aluminé in Neuquén province, Argentina. To determine the variations that have occurred in the area, a comprehensive collection of bibliographic data is analyzed and interpreted, together with unpublished data from 39 ° S 71 ° -70 ° W, and a selection of geochemical graphics of major elements (TAS and AFM ), trace elements (La / Yb vs Distance to the pit; La / Nb vs La; Ba / La vs La / Sm; Ba / Ta vs La / Ta) and rare earths (Spider Diagram). The results obtained using trace elements such as their distribution (La / Yb vs Distance to the pit), and arc-transarco-intraplate affinity (Ba / Ta vs La / Ta and La / Nb vs La) show that the magmatic activity at the 39 ° S was greater during the Upper Miocene-Pliocene transition, with convergence rates higher than the current ones, generating a volcanic arc with a width greater than the current one. The integration and interpretation of the geochemical data, together with the consideration of the factors that control the position of volcanic arches, allow to generate an evolutionary model for the 39 ° S transect.
The present study tries to reflect the geochemical and compositional variations that determine the architectural evolution of the Pliocene-Quaternary volcanic arc, in the different stages of deformation that have occurred in the western margin of South America. The ZVSC covers between the latitudes of 38 ° -42 ° S, and this study focuses on the 39 ° S area that covers the Araucanía and Los Ríos region, in Chilean territory and the departments of Huilliches and Aluminé in Neuquén province, Argentina. To determine the variations that have occurred in the area, a comprehensive collection of bibliographic data is analyzed and interpreted, together with unpublished data from 39 ° S 71 ° -70 ° W, and a selection of geochemical graphics of major elements (TAS and AFM ), trace elements (La / Yb vs Distance to the pit; La / Nb vs La; Ba / La vs La / Sm; Ba / Ta vs La / Ta) and rare earths (Spider Diagram). The results obtained using trace elements such as their distribution (La / Yb vs Distance to the pit), and arc-transarco-intraplate affinity (Ba / Ta vs La / Ta and La / Nb vs La) show that the magmatic activity at the 39 ° S was greater during the Upper Miocene-Pliocene transition, with convergence rates higher than the current ones, generating a volcanic arc with a width greater than the current one. The integration and interpretation of the geochemical data, together with the consideration of the factors that control the position of volcanic arches, allow to generate an evolutionary model for the 39 ° S transect.
Notas
Tesis (Geólogo)
Palabras clave
Geoquímica Ambiental, Cordillera de Los Andes (Chile), Zonas de Subducción, Estudios Comparados, Instrumentos de Medición