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UNIVERSIDAD AUSTRAL DE CHILE Facultad De Ciencias Escuela De Geología UNIVERSIDAD AUSTRAL DE CHILE Facultad de Ciencias Escuela de Geología PROFESOR PATROCINANTE: DR. ALEXANDRE CORGNE INSTITUTO DE CIENCIAS DE LA TIERRA FACULTAD DE CIENCIAS CLASIFICACIÓN DE LOS METEORITOS DEL DESIERTO DE ATACAMA SAN JUAN 086 Y TALTAL 001 REPRESENTADOS EN LAS MUESTRAS AIUC-01 Y AIUC-2 Seminario de Graduación presentado como parte de los requisitos para optar al Título de Geólogo RODRIGO EDMUNDO ECHEVARRÍA HENRY VALDIVIA-CHILE Mayo 2020 MIEMBROS DE LA COMISIÓN PROFESOR PATROCINANTE: Dr. Alexandre Corgne Instituto de Ciencias de la Tierra Facultad de Ciencias Universidad Austral de Chile PROFESOR COPATROCINANTE: Dra. Millarca Valenzuela Picón Departamento de Ciencias Geológicas Facultad de Ingeniería y Ciencias Geológicas Universidad Católica del Norte PROFESOR INFORMANTE: Ldo. Gabriel Pinto Morales Instituto de Astronomía y Ciencias Planetarias de Atacama Universidad de Atacama AGRADECIMIENTOS. El presente Seminario de Graduación fue parcialmente financiado por el proyecto DID S-2017-13, cuyo investigador responsable es el Dr. Alexandre Corgne junto a la Dra. Millarca Valenzuela Picón, y el proyecto FONDECYT Nº11171090 a cargo de la Dra. Millarca Valenzuela Picón que financio los análisis QEMSCAN realizados. Para empezar, me gustaría agradecer al Dr. Alexandre Corgne por la oportunidad de estudiar y trabajar en un área de la geología que era completamente ajena a mí, llevándome a explorar más sobre lo que actualmente considero es una de las partes más bellas e interesantes de esta. Además de agradecer su paciencia y disponibilidad que me ha brindado para ayudarme a realizar este trabajo. A la Dra. Millarca Valenzuela por dedicarse a enseñarme las bases prácticas y teóricas necesarias para poder realizar mi trabajo, junto con mostrarme la dedicación y motivación que me inspiraron al hacerlo. Al cuerpo docente del Departamento de Ciencias de la Tierra de la Universidad Austral que me formaron para llegar donde estoy actualmente. Especialmente al Dr. Mario Pino por ser siempre más que un profesor para resolver todo tipo de problemas. Agradezco a mi familia por su inagotable apoyo durante toda mi vida que me ha llevado a alcanzar lo que he querido, siendo siempre un ejemplo de esfuerzo y dedicación inigualable. A mis amigos tanto viejos como nuevos que siempre se preocuparon por mí y estuvieron siempre presentes durante estos años. En especial a los que me ayudaron a terminar mi trabajo cuando no me quedaban energías para seguir como Guti, la Isi, la Gladys y el Mago. A Ana Javiera le agradezco por ser gran parte de mi alegría durante mi etapa universitaria, junto con mi confidente. Índice de contenidos 1. RESUMEN ......................................................................................................................................... 1 1.1. Abstract ....................................................................................................................................... 3 2. INTRODUCCIÓN .......................................................................................................................... 5 2.1. Fundamentos de Meteorítica ................................................................................................. 5 2.2. Objetivo general ........................................................................................................................ 7 2.3. Objetivos específicos ............................................................................................................... 7 3. MATERIALES Y MÉTODOS ..................................................................................................... 9 3.1. Área de hallazgo de los meteoritos ...................................................................................... 9 3.2. Metodología de clasificación ............................................................................................... 11 3.2.1. Clasificación primaria .................................................................................................... 11 3.2.2. Clasificación secundaria, terciaria y post caída ..................................................... 14 3.2.2.1. Tipo Petrológico ......................................................................................................... 17 3.2.2.2. Metamorfismo de choque.......................................................................................... 21 3.2.2.3. Meteorización terrestre .............................................................................................. 29 3.2.3. Propiedades mineralógicas de los condritos ........................................................... 32 3.3. Técnicas analíticas de Laboratorio .................................................................................... 39 3.3.1. Microscopio óptico ......................................................................................................... 39 3.3.2. Microscopio electrónico de barrido ........................................................................... 40 3.3.3. QEMSCAN ....................................................................................................................... 41 3.3.4. Susceptibilidad magnética ........................................................................................... 41 4. RESULTADOS ............................................................................................................................... 46 4.1. Susceptibilidad magnética ................................................................................................... 46 4.2. Descripción macroscópica ................................................................................................... 47 4.2.1. Muestra AIUC-01 ............................................................................................................. 47 4.2.2. Muestra AIUC-02 ............................................................................................................ 48 4.3. Descripción microscópica .................................................................................................... 49 4.3.1. Muestra AIUC-01 ............................................................................................................. 49 4.3.1.1. Características texturales ............................................................................................ 49 4.3.1.2. Cóndrulos .................................................................................................................... 54 4.3.1.3. Matriz ............................................................................................................................ 57 4.3.1.4. Mineralogía Primaria .................................................................................................. 60 4.3.1.5. Características composicionales ................................................................................ 64 4.3.1.6. Resumen de los principales componentes de la muestra AIUC-01. ................... 70 4.3.2. Muestra AIUC-02 ............................................................................................................ 70 4.3.2.1. Características texturales ............................................................................................ 70 4.3.2.2. Cóndrulos .................................................................................................................... 73 4.3.2.3. Matriz ............................................................................................................................ 76 4.3.2.4. Mineralogía Primaria .................................................................................................. 77 4.3.2.5. Características composicionales ................................................................................ 80 4.3.2.6. Resumen de los principales componentes de la muestra AIUC-02 .................... 81 4.4. Datos químicos ........................................................................................................................ 82 4.4.1. Análisis químico SEM ............................................................................................... 82 4.4.2. Datos QEMSCAN. ..................................................................................................... 82 4.5. Evidencias de Metamorfismo de choque ........................................................................ 86 4.5.1. Muestra AIUC-01 ............................................................................................................. 86 4.5.2. Muestra AIUC-02 ............................................................................................................ 93 4.6. Mineralogía Secundaria ........................................................................................................ 94 4.6.1. Muestra AIUC-01 ............................................................................................................. 94 4.6.2. Muestra AIUC-02 ............................................................................................................ 96 5. DISCUSIÓN .................................................................................................................................... 99 5.1. Clasificación Primaria ............................................................................................................ 99 5.2. Tipo Petrológico ..................................................................................................................... 99 5.2.1. Muestra AIUC-01 ...........................................................................................................100
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