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El Pluma.Pdf (1.942Mo) ISSN 0328-2333 Programa Nacional de Cartas Geológicas de la República Argentina 1:250.000 Hoja Geológica 4769-I El Pluma Terrazas fluviales del cañadón El Pluma en estancia Maremma. Provincia de Santa Cruz Julio Carlos Cobos y José Luis Panza Recursos Minerales: Mario A. Zubia Petróleo y gas: Eduardo G. Figari Guillermo Cardinali Mónica Lucero Marcelo Borderas Boletin Nº 319 Buenos Aires - 2003 Programa Nacional de Cartas Geológicas de la República Argentina 1:250.000 Hoja Geológica 4769–I El Pluma Provincia de Santa Cruz Julio Carlos Cobos y José Luis Panza Recursos Minerales Depósitos metalíferos: Mario A. Zubia Petróleo y gas: Eduardo G. Figari* Guillermo Cardinali* Mónica Lucero* Marcelo Borderas* *Departamento Reservorios-Exploración, División Regional Sur, REPSOL-YPF, ARGENTINA Normas, dirección y supervisión del Instituto de Geología y Recursos Minerales SERVICIO GEOLÓGICO MINERO ARGENTINO INSTITUTO DE GEOLOGÍA Y RECURSOS MINERALES Boletín Nº 319 Buenos Aires–2003 SECRETARIO DE MINERÍA Jorge Mayoral SERVICIO GEOLÓGICO MINERO ARGENTINO Secretario Ejecutivo: Pedro Alcántara INSTITUTO DE GEOLOGÍA Y RECURSOS MINERALES Roberto F. Page DIRECCIÓN DE GEOLOGÍA REGIONAL José E. Mendía SEGEMAR Avenida Julio A. Roca 651 • 10º Piso • Telefax 4349-4450/3115 (C1067ABB) Buenos Aires • República Argentina www.segemar.gov.ar / [email protected] Referencia bibliográfica COBOS, J. C. y J. L. PANZA, 2003. Hoja Geológica 4769-I, El Pluma. Provincia de Santa Cruz. Instituto de Geología y Re- cursos Minerales, Servicio Geológico Minero Argentino. Bole- tín 319, 89 p. Buenos Aires. ISSN 0328–2333 Es propiedad del SEGEMAR • Prohibida su reproducción CONTENIDO RESUMEN ...................................................................................................... 1 ABSTRACT ..................................................................................................... 2 1. INTRODUCCIÓN ..................................................................................................... 3 Ubicación de la Hoja y área que abarca ................................................................................... 3 Naturaleza del trabajo ...................................................................................................... 3 Investigaciones anteriores ...................................................................................................... 4 2. ESTRATIGRAFÍA ...................................................................................................... 4 2.1. Mesozoico ...................................................................................................... 5 2.1.1. Jurásico ...................................................................................................... 5 2.1.1.1 Dogger ...................................................................................................... 5 Formación Bajo Pobre .................................................................................. 5 2.1.1.2. Dogger - Malm ...................................................................................................... 7 Grupo Bahía Laura .............................................................................................. 7 Formación Chon Aike ................................................................................... 9 Formación La Matilde ................................................................................ 16 2.1.2. Cretácico .................................................................................................... 18 2.1.2.1. Inferior - superior .................................................................................................... 18 Grupo Chubut .................................................................................................... 18 Formación Castillo ...................................................................................... 19 Formación Bajo Barreal ............................................................................. 22 Formación Laguna Palacios ....................................................................... 25 Relaciones estratigráficas del Grupo Chubut ...................................................... 25 Ambiente de depositación del Grupo Chubut ..................................................... 28 Edad del Grupo Chubut ..................................................................................... 28 2.2. Cenozoico .................................................................................................... 28 2.2.1. Paleógeno .................................................................................................... 28 2.2.1.1. Paleoceno .................................................................................................... 28 Formación Salamanca ................................................................................. 28 Formación Río Chico .................................................................................. 31 2.2.1.2. Eoceno .................................................................................................... 32 Basalto Cerro del Doce .............................................................................. 32 2.2.1.3. Oligoceno .................................................................................................... 36 Formación (Grupo) Sarmiento .................................................................... 36 Basalto Alma Gaucha ................................................................................. 37 2.2.2. Paleógeno - Neógeno .................................................................................................... 39 2.2.2.1. Oligoceno superior - Mioceno inferior ..................................................................... 39 Formación Monte León ............................................................................... 39 2.2.3. Neógeno .................................................................................................... 41 2.2.3.1. Mioceno .................................................................................................... 41 2.2.3.1.1. Mioceno inferior ................................................................................................ 41 Formación Santa Cruz................................................................................. 41 2.2.3.1.2 Mioceno medio .................................................................................................. 44 Basalto de las Lagunas Sin Fondo ............................................................... 44 2.2.3.1.3. Mioceno medio y superior ................................................................................. 47 Depósitos de agradación (Niveles I, II y III) ............................................... 47 2.2.3.1.4. Mioceno superior ............................................................................................... 47 Depósitos de agradación (Niveles IV y V) ................................................... 47 Depósitos de terrazas fluviales del cañadón Salado y otros (Nivel I)........... 49 2.2.3.2. Mioceno superior - Plioceno inferior ........................................................................ 49 Basalto Cerro Tejedor ................................................................................. 49 2.2.3.3. Plioceno .................................................................................................... 50 2.2.3.3.1. Plioceno inferior ................................................................................................. 50 Depósitos de terrazas fluviales del cañadón Salado y otros (NivelesII y III) ......................................................................................... 50 2.2.3.3.2. Plioceno inferior a superior................................................................................ 51 Depósitos de terrazas fluviales del río Senguerr (Niveles I, II y III).......... 51 Depósitos de terrazas fluviales del río Deseado y del cañadón El Pluma (Niveles I, II y III) ...................................................................................... 51 2.2.3.3.3. Plioceno superior ............................................................................................... 52 Basalto Cerro Piedras .................................................................................. 52 2.2.4. Neógeno superior - Cuaternario ..................................................................................... 53 2.2.4.1. Plioceno superior - Pleistoceno inferior ................................................................... 53 Depósitos de terrazas fluviales del río Senguerr (Niveles IV y V) ............ 53 Depósitos de terrazas fluviales del río Deseado y del cañadón El Pluma (Niveles IV y V) .......................................................................................... 54 2.2.5. Cuaternario .................................................................................................... 54 2.2.5.1. Pleistoceno .................................................................................................... 54 Depósitos de morena frontal (Estadío Inicioglacial)..................................... 54 Depósitos glacifluviales (Estadío Inicioglacial)............................................. 54 Depósitos de morena frontal (Estadío Daniglacial) ...................................... 55 Depósitos glacifluviales (Estadío Daniglacial) .............................................. 55 Depósitos de terrazas fluviales
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