Petrogenesis of Miocene volcanic arc rocks over the Chilean- Pampean flat-slab segment of the Central Andes constrained by mineral chemistry
DOI:
https://doi.org/10.1344/105.000002081Keywords:
Andesitic, Geothermobarometry, Volcanisme, Crustal thickness, Valle del Cura, Argentina, ChileAbstract
Miocene arc volcanism is manifested widely in the Valle del Cura-El Indio belt region (29°30´–30° South latitude), in the southern Central Andes of Argentina and Chile. The magmas that fed this volcanism are well represented by the Cerro de las Tórtolas Formation, which is divided into two volcanic episodes based on petrographic, chemical and age differences: an older basaltic-andesitic event (16–14Ma) and a younger andesitic to dacitic (13–10Ma) one. Representative plagioclase, orthopyroxene, clinopyroxene and amphibole phenocrysts from rock samples already characterized from geochemical and isotopic viewpoints were selected for electron microprobe determination of mineral chemistry. Results indicate an overall homogeneous composition for each of the mineral phases. Equilibrium temperatures were estimated through two-pyroxenes, amphibole-plagioclase and amphibole geothermometers, which show a consistent temperature range between 970 to 850°C. Equilibrium pressure calculated using amphibole composition for volcanic suites produced the most comprehensive results for pressure equilibrium conditions, with results close to 4kb. Changes in the residual mineral assemblages and variations in isotopic signatures indicate that primary magmas were equilibrated at the lower crust with a gradual increase of crustal thickness. These melts evolved towards intermediate magma chambers, where crystallization of phenocrysts occurred at the same temperature and pressure conditions, hence, no increase in depth of intermediate magma chambers is registered although the increase of crustal thickness registered from Lower to Middle Miocene times.References
Barckhausen, U., Ranero, C.R., Cande, S.C., Engels M., Weinrebe, W., 2008. Birth of an intraoceanic spreading center. Geology, 36(10), 767-770.
Bissig, T., Clark, A.H., Lee, J.K.W., Heather, K.B., 2001. The Cenozoic history of volcanism and hydrothermal alteration in the Central Andean flat-slab region: New 40Ar-39Ar constrains from the El Indio-Pascua Au-Ag-Cu belt, 29°20-30°30” S. International Geology Review, 43, 312-340.
Bissig, T., Clark, A.H., Lee, J.K.W, von Quadt, A., 2003. Petrogenetic and metallogenetic responses to Miocene slab flattenig: New constrains from the El Indio-Pascua Au-Ag-Cu Belt, Chile/Argentina. Mineralium Deposita, 38(7), 844-862.
Brey, G.P., Köhler, T., 1990. Geothermobarometry in fourphase lherzolites II. New thermobarometers, and practical assessment of existing thermobarometers. Journal of Petrology 31(6), 1353-1378.
Deer, W.A., Howie, R.A., Zussman, J., 1992. The rocks-forming minerals. Harlow, Logman Scientific & Technical, 2nd edition, 696pp.
Fonarev, V.I., Graphchikov, A.A., 1991. Two pyroxene thermometry: a critical evaluation. In: Perchuk, L.L. (ed.). Progress in metamorphic and magmatic petrology. Cambridge, Cambridge University Press, 65-92.
Helz, R.T., 1982. Phase relations and compositions of amphiboles produced in studies of the melting behaviour of rocks. Mineralogical Society of America Reviews in Mineralogy, 9B, 279-346.
Hildreth, W., Moorbath, S., 1988. Crustal contributions to arc
magmatism in the Andes of Central Chile. Contribution to Mineralogy and Petrology, 98(4), 455-489.
Holland, T., Blundy, J., 1994. Non-ideal interactions in calcic amphibole and their bearing on amphibole–plagioclase thermometry. Contributions to Mineralogy and Petrology 116(4), 433-447.
Hollister, L.S., Grissom, G.C., Peters, E.K., Stowell, H.H., Sisson, V.B., 1987. Confirmation of the empirical correlation of aluminum in hornblende with pressure of solidification of calcalkaline plutons. American Mineralogy, 72(3-4), 231-239.
Jarosewich, E., Nelen, J.A., Norberg, J.A., 1980, Reference samples for electron microprobe analysis. Geostandards Newsletter, 4, 43-47.
Johnson, M., Rutherford, M., 1989. Experimental calibration of the Al-in-horblende geobarometer with application to Long
Valley caldera (California) volcanics rocks. Geology, 17(10), 937-841.
Jones, J. P., Martínez, R., Rossello, E., 1996. La Faja volcánica terciaria del Valle del Cura (San Juan, Argentina): sus alcances
y potencial para localizar World Class Deposits. In: Ramos, V.R., (ed.). Actas del XIII Congreso Geológico y III Congreso de Exploración de Hidrocarburos 3, Buenos Aires, 55-71.
Kay, M.S., Abbruzzi, J.M., 1996. Magmatic evidence for neogene lithospheric evolution of the Central Andes “flat slab” between 30°S and 32°S. Tectonophysics, 259, 15-28.
Kay, S.M., Gordillo, C.E., 1994. Pocho volcanic rocks and the melting of depleted continental lithosphere above a shallowly dipping subduction zone in the central Andes. Contributions to Mineralogy and Petrology, 117, 25-44.
Kay, S.M., Mpodozis, C., 2002. Magmatism as a probe to Neogene shallowing of the Nazca plate beneath the modern Chilean flat-slab. Journal of South American Earth Science, 15(1), 39-57.
Kay, S.M., Maksaev, V.A., Moscoso, R., Mpodozis, C., Nasi, C., 1987. Probing the evolving Andean lithosphere: Mid-Late Tertiary Magmatism in Chile (29°-30°30’S) over the modern zone of subhorizontal subduction. Journal of Geophysical Research, 92(B7), 6173-6189.
Kay, M.S., Maksaev, V.A., Moscoso, R., Mpodozis, C., Nasi, C., Gordillo, C.E., 1988. Tertiary Andean Magmatism in Chile and Argentina between 28°S and 33°S: Correlation of magmatic chemistry with changing Benioff zone. Journal South American Geology Earth Sciences, 1(1), 21-38.
Kay, S.M., Mpodozis, C., Ramos, V.R., Munizaga, F., 1991. Magma source variations for mid-late Tertiary magmatic rocks associated with shallowing zone and thickening crust in the central Andes (28° to 33°S). In: Harmon, R.S., Rapela, C.W. (eds.). Andean magmatism and its tectonic setting. Geological Society of America, 265 (Special Paper), 113-137.
Kay, S.M., Mpodozis, C., Coira, B., 1999. Neogene magmatism, tectonism and mineral deposits of the Central Andes (22º-23ºS latitude). In: Skinner, B.J. (ed.). Geology and Ore Deposits of the Central Andes. Society of Economic Geologists, 7 (Special Publication), 27-59.
Kay, S.M., Godoy, E., Kurtz, A., 2005. Episodic arc migration, crustal thickening, subduction erosion and magmatism in the South-Central Andes. Geological Society of American Bulletin, 117(1-2), 67-88.
Leake, B.E., Woolley, A.R., Arps, C.E.S., Birch, W.D., Gilbert, M.C., Grice, J.D., Hawthorne, F.C., Kato, A., Kisch, H.J., Krivovichev, V.G., Linthout, K., Laird, J., Mandarino, J.A., Maresch, W.V., Nickel, E.H., Rock, N.M.S., Schumacher, J.C., Smith, D.C., Stephenson, N.C.N., Ungaretti, L., Whittaker, E.J.W., Guo, Y., 1997. Nomenclature of amphiboles of the International Mineralogical Association, Commission on New Minerals and Mineral Names. American Mineralogist, 82(11-12), 1019-1037.
Limarino, C.O., Gutiérrez, P.R., Malizia, D., Barreda, V., Page, S., Ostera, H., Linares, E., 1999. Edad de las secuencias paleógenas y neógenas de las cordilleras de la Brea y Zancarrón, Valle del Cura, San Juan. Revista de la Asociación Geológica Argentina, 54(2), 177-181.
Lindsley, D.H., Frost, B.R., 1992. Equilibria among Fe-Ti oxides, pyroxenes, olivine and quartz: Part I. Theory. American Mineralogist 77(9-10), 987-1003.
Litvak, V.D., 2009. El volcanismo Oligoceno Superior–Mioceno Inferior del Grupo Doña Ana en la alta cordillera de San Juan. Revista de la Asociación Geológica Argentina, 64(2), 200-212.
Litvak, V.D., Poma, S., 2005. Estratigrafía y facies volcánicas y volcaniclásticas de la Formación Valle del Cura: magmatismo paleógeno en la Cordillera Frontal de San Juan. Revista de la Asociación Geológica Argentina, 60(2), 402-416.
Litvak, V.D., Poma, S., Limarino, C.O., 2004. Volcanismo piroclástico de edad miocena media en el Valle del Cura, provincia de San Juan: nuevos datos geológicos y geocronológicos. Revista de la Asociación Geológica Argentina, 59(3), 514-517.
Litvak, V.D., Poma, S., 2010. Geochemistry of mafic Paleocene volcanic rocks in Valle del Cura region: Implications for the petrogenesis of primary mantle-derived melts over the Pampean flat-slab. Journal of South American Earth Science, 29(3), 705-716.
Litvak, V.D., Chernicoff, C.J., Poma, S., 2005a. Localización de centros eruptivos mediante aeromagnetometría en el sector central del Valle del Cura, San Juan, Argentina: implicancias para la evolución de arco/retroarco Cenozoico. Revista Geológica de Chile, 32(1), 77-93.
Litvak, V.D., Kay, S.M., Mpodozis, C., 2005b. New K/Ar ages on tertiary volcanic rocks in the Valle del Cura, Pampean flat slab segment, Argentina. In: Llambías, E., de Barrio, R., González, P., Leal, P. (eds.). Actas del XVI Congreso Geológico Argentino 2, La Plata, 159-164.
Litvak, V.D., Page, S., 2002. Nueva evidencia cronológica en el Valle del Cura, provincia de San Juan. Revista de la Asociación Geológica Argentina, 57(4), 483-486.
Litvak, V.D., Poma, S., Kay, S.M., 2007. Paleogene and Neogene magmatism in the Valle del Cura region: a new perspective on the evolution of the Pampean flat slab, San Juan province, Argentina. Journal of South American Earth Science, 24(2-4), 117-137.
Maksaev, V., Moscoso, R., Mpodozis, C., Nasi, C., 1984. Las unidades volcánicas y plutónicas del Cenozoico superior entre la Alta Cordillera del Norte Chico (29°-31°S), Geología, alteración hidrotermal y mineralización. Revista Geológica de Chile, 21(1), 11-51.
Malizia, D., Limarino, C.O., Sosa-Gomez, J., Kokot, R., Nullo, F., Gutierrez, P., 1997a. Descripción de la Hoja Geológica Cordillera del Zancarrón, escala 1:100.000. Buenos Aires, Secretaría de Minería de la Nación, 280pp.
Martin, M.W., Clavero, J.R., Mpodozis, C.M., 1997a. Eocene to Late Miocene structural development of El Indio belt, 30°S, North-Central Chile. In: Universidad Católica del Norte (ed.). Actas del VIII Congreso Geológico Chileno 1, Antofagasta, 144-148.
Martin, M.W., Clavero, J.R., Mpodozis, C.M., 1997b. Eocene to Late Miocene magmatic development of El Indio belt, 30°S, North-Central Chile. In: Universidad Católica del Norte (ed.). Actas del VIII Congreso Geológico Chileno 1, Antofagasta, 149-153.
Masuda, A., Nakamura, N., Tanaka, T., 1973. Fine structures of mutually normalizad rare Herat patterns of chondrites. Geochimica et Cosmochimica Acta, 37, 239-248.
Miyashiro, A., 1974. Volcanic rock series in island arcs and continental margins. American Journal of Science, 274, 321-355.
Morimoto, N., 1989. Nomenclature of pyroxenes. Canadian Mineralogist, 43(1), 143-156.
Nasi, C.P., Moscoso, R.D., Maksaev, V.J., 1990. Hoja Guanta, Región de Coquimbo, Carta Geológica de Chile N° 67. Santiago de Chile, Servicio de Geología y Minería, 140pp.
Pardo Casas, F., Molnar, P., 1987. Relative motion of the Nazca (Farallón) and South America plates since Late Cretaceous time. Tectonics, 6(3), 233-248.
Peccerillo, A., Taylor, S.R., 1976. Geochemistry of Eocene calc-alkaline volcanic rocks from the Kastamonu area, northern Turkey. Contributions to Mineralogy and Petrology, 58, 63-81.
Putirka, K., 2008. Thermometers and barometers for volcanic systems. In: Putirka, K., Tepley III, F. (eds.). Minerals, Inclusions and Volcanic Processes. Reviews in Mineralogy and Geochemistry, Chantilly, Mineralogical Society of American, 69, 61-120.
Ramos, V.A., Kay, S.M., Page, R., Munizaga, F., 1989. La Ignimbrita Vacas Heladas y el cese del volcanismo en el Valle del Curá, província de San Juan. Revista de la Asociación Geológica Argentina, 44(1-2), 336-352.
Ramos, V.A., Cristallini, E.O., Pérez, D.J., 2002. The Pampean flat-slab of the Central Andes. Journal of South American Earth Sciences, 15(1), 59-78.
Ridolfi, F, Renzulli, A, Puerini, M., 2010. Stability and chemical equilibrium of amphibole in calcalkaline magmas: an overview, new thermobarometric formulations and application to subduction-related volcanoes. Contributions to Mineralogy and Petrology, 160(1), 45-66.
Schmidt, M., 1992. Amphibole composition in tonalite as a function of pressure; An experimental calibration of the Alin-hornblende barometer. Contributions to mineralogy and petrology, 110(2-3), 421-423.
Shelley, D. 1993. Igneous and metamorphic rocks under the microscope: classification, textures, microstructures and mineral preferred orientation. Springer, 445 pp., Chapman and Hall, London.
Tibaldi, A.M., Álvarez-Valero, A.M., Otamendi, J.E., Cristofollini, E.A., 2011. Formation of paired pelitic and gabbroic migmatites: An empirical investigation of the consistency of geothermometers, geobarometers and pseudosections. Lithos, 122(1-2), 57-75.
Winocur, D., 2005. Geología y estructura de la región de los Despoblados, Provincia de San Juan. Licenciatura Thesis. Buenos Aires, Universidad de Buenos Aires, 123pp.
Winocur, D.A., Litvak, V., Ramos, V.A., 2014. Magmatic and tectonic evolution of the Oligocene Valle del Cura basin, Main Andes of Argentina and Chile: Evidence for generalized extension. In: Sepúlveda, S., Giambiagi, L., Pinto, L., Moreiras, S., Tunik, M., Hoke, G., Farías, M. (eds.). Geodynamic Processes in the Andes of Central Chile and Argentina. Geological Society of London, 399 (Special Publications), http://dx.doi.org/10.1144/SP399.2
Yañez, G.A., Ranero, C.R., von Huene, R., Díaz, J., 2001. Magnetic anomaly interpretation across the southern central Andes (32°–34°): the role of the Juan Fernández Ridge in the late Tertiary evolution of the margin. Journal of Geophysical Research, 106(B4), 6325-6345.
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