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Programa Del Curso Posgrado: Geología Del Basamento. La Aportación De La Geocronología

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Programa Del Curso Posgrado: Geología Del Basamento. La Aportación De La Geocronología Programa del Curso Posgrado: Geología del Basamento. La aportación de la Geocronología. Docente: Dr. Cesar Casquet Objetivos El curso va dirigido a estudiantes de posgrado que incluyen en sus temas de tesis la investigación de las unidades del basamento cristalino. El principal objetivo del curso es mostrar diferentes modalidades de abordaje en el estudio geocronológico de rocas ígneas y metamórficas en función del problema que se pretende resolver. No se trata de un curso de geología de basamento en general, ni de aspectos teóricos de la geocronología, sino de geocronología aplicada a la resolución de problemas inherentes a la geología de basamento. Para el cursado del mismo se requieren conocimientos básicos de los diferentes métodos geocronológicos aplicados a rocas antiguas y de geología general de rocas ígneas y metamórficas. Durante el dictado del curso se expondrán y discutirán diferentes ejemplos de aplicaciones geocronológicas a la resolución de problemas del basamento cristalino de las Sierras Pampeanas de Argentina. Se expondrá principalmente la experiencia acumulada como resultado de las investigaciones realizada desde el año 1993 por el grupo de investigación PAMPRE. El curso concluirá con una clase/conferencia dedicada a resumir precisamente la interpretación sobre la evolución de las Sierras Pampeanas desde el Proterozoico medio hasta el Paleozoico inferior y una excursión de campo. Programa del Curso 1era Parte (incluye las actividades de la mitad del primer día) Introducción al Problema de la datación en el basamento: 1-Definición del término basamento cristalino. 2-Principales problemas que plantea el estudio de las unidades de basamento. 3-El principal problema de la geología de basamento: Las edades de los eventos magmáticos, metamórficos y deformacionales. 4- ¿Que se puede datar y que no en un basamento? 5- Fundamentos físicos de la geocronología y sistemáticas útiles en basamento. 6- Los principales métodos geocronológicos. 7-Temperatura de Cierre (Closure TC). Como escoger la sistemática mas adecuada. 8-Edades Modelo (Nd y Hf). Significado y utilidad en un basamento. 9-Datación de rocas metacarbonatadas. 2da Parte (incluye las actividades de la mitad del primer y segundo día) Geocronología aplicada a casos del basamento Pampeano: 10- Edades de cristalización magmática. a) Isocronas de roca total (Rb-Sr y Sm-Nd): b) K-Ar en Ms y Bt en pegmatitas. c) Datación “in situ” (U-Pb en Zr). 11- Datación de eventos hidrotermales, Isocrona Sm-Nd en fluoritas. 12- Edades de metamorfismo y de deformación (foliaciones y fallas): a) Isocronas WR-Grt (Sm-Nd). b) Edades aparentes K-Ar y Ar-Ar (RT y minerales). c) Datación “in situ” (U-Pb en zircones y Mo). d) Datación CHIME (U-Th-Pb en monacitas). e) Edades U-Pb (TIMS) en Columbitas. 13- Análisis de la edad y procedencia de rocas metasedimentarias a partir de Zr detríticos. 14-Edades Modelo (Nd y Hf). 16. Edades de mármoles basadas en la composición isotópica del Sr (blind dating). 17-Aplicaciónes en las reconstrucciones paleogeográficas. 3ra Parte (última mitad del segundo día) Conferencia final: El basamento Pampeano: Un caso singular de complejidad geológica visto a la luz de los nuevos métodos geocronológicos. 4ta parte: Salida de campo (actividades del tercer día) Visita a los afloramientos del basamento de la Sierra de Córdoba. Aplicación de los métodos de campo en el estudio de las rocas ígneas y metamórficas. Bibliografía General Específica Galindo, C, Pankhurst, R. J.; Casquet, C; Coniglio, J.; Baldo, E.; Rapela C. W. & Saavedra J. 1997. Age, Sr and Nd-Isotope Systematics and origin of two Fluorite Lodes, Sierras Pampeanas, Argentina. International Geology Review, volumen 39 Nº 10: 948-954. Rapela, C.W., Pankhurst, R . J., Casquet, C. Baldo, E. Saavedra, J. and Galindo, C., 1998 Early evolution of the Proto-Andean margin of South America. Geology, vol. 26 (8), 707-710. Casquet, C., Baldo, E., Pankhurst, R. J., Rapela C. W., Galindo, C., Fanning, C. M. and Saavedra J., 2001, Involment of the Argentine Precordillera Terrane in the Famatinian Mobile Belt: Geochronological (U-Pb SHRIMP) and Metamorphic evidence from Sierra de Pie de Palo.¨ Geology Vol. 29, Nº 8 : 703-706. Galindo, C., Casquet, C., Baldo, E. G., Pankhurst R., Rapela C. y Saavedra J., 2004 Sr, C and O Isotope Geochemistry of Carbonates from Sierra de Pie de Palo and other Western Sierras Pampeanas (Argentina). Stratigraphy and Constraints on the Derivation of the Precordillera Terrane. Precambrian Research. Vol. 131: 5 7-71. Fanning, C.M. , Pankhurst, R.J., Rapela, C.W., Baldo, E.G., Casquet, C., 2004 K-Bentonites in the Argentine Precordillera Contemporaneous with Rhyolite Volcanism in the Famatinian Arc. Journal of the Geological Society of London Vol. 161: 747-756. Casquet, C., Rapela, C. W., Pankhurst, R.J., Galindo, C., Dahlquist, J., Baldo, E. G., Saavedra, J., Gonzalez Casado, J.M., Fanning, M. 2005 Grenvillian massif-type anorthosites in the Sierras Pampeanas (Argentina). Journal of Geological Society of London, vol. 162: 9-12 E. Baldo, Casquet, C., R. J. Pankhurst, C. Galindo, C. W. Rapela , M. Fanning, J. A. Dahlquist and J. Murra. 2006. Neoproterozoic A-type granitic magmatism in the Western Sierras Pampeanas (Argentina): evidence for Rodinia break-up along a proto-Iapetus rift?. Terra Nova. Vol. 18: 388–394. ISNN 0954-4879 Casquet, C., C. W. Rapela, R. J. Pankhurst, M. Fanning, E. Baldo, J. M. González-Casado, C. Galindo, and J. A. Dahlquist. 2006. U-Pb SHRIMP zircon dating of Grenvillian metamorphism in Western Sierras Pampeanas (Argentina): correlation with the Arequipa–Antofalla craton and constraints on the extent of the Precordillera Terrane. Gondwana Research Letter Vol. 9: 524-529. Rapela, C. W. R.J. Pankhurst, C. Casquet, C. M. Fanning, E. Baldo, J. M. González-Casado, C. Galindo, and J. A. Dahlquist. 2007: The Rio de la Plata craton and the assembly of SW Gondwana Earth Science Reviews. Vol 83/1-2 pp 49-82. ISNN-0012-8252. Casquet, C. R.J. Pankhurst, C.W. Rapela, C. Galindo, C.M. Fanning, M. Chiaradia, E. Baldo, J.M. González-Casado and J. Dahlquist. 2007: The Mesoproterozoic Maz Terrane in the Western Sierras Pampeanas, Argentina, equivalent to the Arequipa-Antofalla block of southern Peru? Implications for West Gondwana margin evolution Gondwana Research. 13:163-175. Casquet C., R.J. Pankhurst, C. Galindo, C. Rapela, C.M. Fanning, E. Baldo, J. Dahlquist, J.M. González Casado & F. Colombo. 2008. A deformed alkaline igneous rock – carbonatite complex from the Western Sierras Pampeanas, Argentina: evidence for late Neoproterozoic opening of the Clymene Ocean? Precambrian Research 165: 205-220. (ISSN: 0301-9268). Colombo, Fernando; Edgardo G. Baldo; Cesar Casquet, Robert J. Pankhurst; Carmen Galindo; Carlos W Rapela; Juan A Dahlquist; Mark Fanning. 2009. A-type magmatism in the Sierras of Maz and Espinal: A new record of Rodinia break-up in the Western Sierras Pampeanas of Argentina. Precambrian Research. 175. 77-86 (ISSN: 0301-9268). Rapela, C. W., R. J. Pankhurst, C. Casquet, E. Baldo, C. Galindo, C.M. Fanning, J. Dahlquist. 2010. The Western Sierras Pampeanas: Protracted Grenville-age history (1330-1030 Ma) of intra-oceanic arcs, subduction-acretion at continental-edge and AMCG intraplate magmatism. Journal of South American Earth Sciences. Vol.29. 105-127 Murra, J. A., E. G. Baldo, C. Galindo, C. Casquet, R. J. Pankhurst, C. W. Rapela, J. Dahlquist. 2010. Sr, C and O isotope composition of marbles from the Sierra de Ancasti, Eastern Sierras Pampeanas, Argentina: age and constraints for the Neoproterozoic–Lower Paleozoic evolution of the proto-Gondwana margin. Geológica Acta Vol. 9: 1-23. Verdecchia, Sebastián O., Cesar Casquet, Edgardo G. Baldo, Robert J. Pankhurst, Carlos W. Rapela, Mark Fanning & Carmen Galindo. 2011. Docking of the Río de la Plata craton to southwestern Gondwana: age constraints from U–Pb SHRIMP detrital zircon ages from Sierras de Ambato and Velasco (Sierras Pampeanas, Argentina). ). Journal of the Geological Society, London. Vol. 168, 2011, pp. 1061 Rapela, C.W., Fanning, C.M., Casquet, C., Pankhurst, R.J., Spalletti, L.A., Poiré, D. & Baldo, E.G.. The Rio de la Plata craton and the adjoining Pan-African/Brasiliano terranes: the record from Rodinia break-up to Gondwana assembly. Gondwana Research Focus, doi: 10.1016/j.gr.2011.05.001 ISSN: 1342-937X. Juan A. Dahlquist, Carlos W. Rapela, Robert J. Pankhurst, C. Mark Fanning, Jeffrey D. Vervoort, Hart Garret, Edgardo G. Baldo, Juan A. Murra, Pablo H. Alasino & Fernando Colombo. Age and Magmatic evolutions of the Ancasti, Sierras Pampeanas, NW. Argentina. Journal of South American Earth Sciences. 34: 10-25, ISNN 0895-981. Iannizzotto, Noelia F., Carlos W. Rapela, Edgardo G. A. Baldo, Carmen Galindo, C. M. Fanning. 2012 The Sierra Norte–Ambargasta Batholith: Cambrian magmatism formed in a transpressional belt along the western edge of the Río de la Plata craton?. En prensa, Journal of South American Earth Sciences. DOI. 10.1016/j.jsames.2012.07.009. Casquet, C., C. Rapela, R.J. Pankhurst, E. Baldo, C. Galindo, C.M. Fanning , J. Dahlquist. 2012. Fast sediment underplating and coeval juvenile magmatism in the Ordovician continental margin of Gondwana, Western Sierras Pampeanas, Argentina. Gondwana Research. Verdecchia, S.O., J. Reche, E. G. Baldo, E. Segovia-Díaz and F.J. Martinez. 2012. Staurolite porphyroblast controls on local bulk compositional and microstructural changes during decompression of a St-Bt-Grt-Crd-And schist (Ancasti metamorphic complex, Sierras Pampeanas, West Argentina). Journal of Metamorphic Geology. doi:10.1111/jmg.12003 Casquet, C., Hervé, F., Pankhurst, R.J., Baldo, E., Calderón, M., Fanning, C. M., Rapela, C.W., Dahlquist, J. 2013. The Mejillonia suspect terrane (northern Chile): Late Triassic fast burial and metamorphism of sediments in a magmatic arc environment extending into the Early Jurassic. Gondwana Research. doi.org/10.1016/j.gr.2013.05.016. Verdecchia, S. O., J. A.
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