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Geología Del Sector NE Del Volcán Copahue Y Geoquímica De Los Fluídos Volcánicos Asociados

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Geología Del Sector NE Del Volcán Copahue Y Geoquímica De Los Fluídos Volcánicos Asociados Tesis de Grado Geología del sector NE del volcán Copahue y geoquímica de los fluídos volcánicos asociados Szentiványi, Juliana Maria 2018 Este documento forma parte de las colecciones digitales de la Biblioteca Central Dr. Luis Federico Leloir, disponible en bibliotecadigital.exactas.uba.ar. Su utilización debe ser acompañada por la cita bibliográfica con reconocimiento de la fuente. This document is part of the digital collection of the Central Library Dr. Luis Federico Leloir, available in bibliotecadigital.exactas.uba.ar. It should be used accompanied by the corresponding citation acknowledging the source. Cita tipo APA: Szentiványi, Juliana Maria. (2018). Geología del sector NE del volcán Copahue y geoquímica de los fluídos volcánicos asociados. Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. https://hdl.handle.net/20.500.12110/seminario_nGEO001109_Szentivanyi Cita tipo Chicago: Szentiványi, Juliana Maria. "Geología del sector NE del volcán Copahue y geoquímica de los fluídos volcánicos asociados". Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. 2018. https://hdl.handle.net/20.500.12110/seminario_nGEO001109_Szentivanyi Dirección: Biblioteca Central Dr. Luis F. Leloir, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Contacto: bibliotecadigital.exactas.uba.ar Intendente Güiraldes 2160 - C1428EGA - Tel. (++54 +11) 4789-9293 UNIVERSIDAD DE BUENOS AIRES Facultad de Ciencias Exactas y Naturales Departamento de Ciencias Geológicas Trabajo Final de Licenciatura Geología del sector NE del volcán Copahue y geoquímica de los fluidos volcánicos asociados Juliana Maria Szentiványi Director: Mariano Agusto Codirector: Alberto Tomás Caselli 2018 II INDICE Resumen ............................................................................................................................................. 1 Agradecimientos ................................................................................................................................. 3 1. Introducción ................................................................................................................................ 5 2. Geología Regional ....................................................................................................................... 7 2.1. Geología Regional y Marco Tectónico ................................................................................. 7 2.1.1. Zona Volcánica Sur ...................................................................................................... 9 2.1.2. Geología del Complejo Volcánico Caviahue Copahue (CVCC) ................................... 11 Zona de Falla Liquiñe Ofqui ....................................................................................................... 11 Lineamiento Callaqui-Copahue-Mandolegüe ........................................................................... 12 Alto de Copahue-Pino Hachado ................................................................................................ 13 Depresión de Loncopué ............................................................................................................ 13 Faja Plegada y Corrida del Agrio ................................................................................................ 13 Zona de Falla Copahue – Antiñir ............................................................................................... 14 Estructuras de la Caldera Caviahue ........................................................................................... 14 Falla Lomín ................................................................................................................................ 14 Grabenes de Caviahue y Trolope .............................................................................................. 15 3. Geología Local ................................................................................................................... 15 3.1 Volcán Copahue ................................................................................................................ 15 3.2 Estratigrafía del CVCC ........................................................................................................ 16 Formación Hualcupén/Formación Cola de Zorro (Plioceno inferior) ........................................ 16 Secuencia Volcánica Las Mellizas (Plioceno Tardío) .................................................................. 17 i. Lavas inferiores ......................................................................................................... 17 ii. Ignimbritas................................................................................................................. 17 iii. Lavas superiores ........................................................................................................ 18 Secuencia Volcánica Copahue ................................................................................................... 18 i. Estadio pre-glaciar ..................................................................................................... 18 ii. Estadio sin-glaciar ...................................................................................................... 18 iii. Estadio post-glaciar ................................................................................................... 19 Oleadas y flujos piroclásticos postglaciares .............................................................................. 19 3.3 Perfiles ............................................................................................................................... 20 3.3.1 Metodología de trabajo de campo y gabinete .......................................................... 20 III 3.3.2 Mapa geológico de la Zona de estudio ..................................................................... 20 3.3.3 Estratigrafía ....................................................................................................................... 22 A. VILLA COPAHUE ......................................................................................................... 22 B. CANTERA LAS MELLIZAS ............................................................................................ 32 C. FLANCO NORESTE del VOLCÁN COPAHUE ................................................................ 34 4. Historia Eruptiva reciente del Volcán Copahue ....................................................................... 48 5. Geoquímica de los fluidos ........................................................................................................ 56 5.1 Marco teórico .................................................................................................................... 56 5.2 Sistema magmático-hidrotermal ...................................................................................... 58 5.2.1 Características de las emisiones gaseosas ................................................................ 62 5.2.2 Características de las aguas superficiales.................................................................. 63 5.3 Metodología ...................................................................................................................... 64 5.3.1 Muestreo de fumarolas ............................................................................................. 65 5.3.2 Muestreo de las Aguas Superficiales ......................................................................... 67 5.4 Resultados ......................................................................................................................... 67 5.4.1 Resultados de las emisiones gaseosas ...................................................................... 68 5.4.2 Resultados de las aguas superficiales ....................................................................... 71 6. Discusión ................................................................................................................................... 78 6.1 Discusión de las emisiones gaseosas ....................................................................................... 78 6.2 Discusión de las aguas superficiales ........................................................................................ 87 6.2.1 Características geoquímicas durante el actual ciclo eurptivo ................................... 87 6.2.2 Variaciones temporales de las composiciones químicas de las aguas superficiales . 93 6.2.3 Relaciones geoquímicas como precursores eruptivos ............................................ 102 7. Conclusiones ........................................................................................................................... 105 ANEXO ............................................................................................................................................. 107 BIBLIOGRAFÍA ................................................................................................................................. 120 IV Resumen La zona de estudio del siguiente trabajo final de licenciatura se ubica en el departamento de Ñorquín, al norte de la provincia de Neuquén, en el límite con Chile. Se estudia la geología del sector nororiental del volcán Copahue (37°51’ S - 71°09’ O, 2977 m.s.n.m) y la geoquímica de los fluidos volcánicos asociados durante el actual ciclo eruptivo (2012-2017). El volcán Copahue se encuentra emplazado en el sudoeste del Complejo Volcánico Copahue- Caviahue y está ubicado en la transición entre los segmentos
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