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Abstract:

In the Sierra de San Luis, Argentina, Sn-enriched granitic pegmatites represent the extremes of fractional crystallization of Ordovician, syn-kinematic, meta- to peraluminous S-type granites. The pegmatites are concordantly emplaced in quartz-mica schist with N-S general strike and vertical dip. The metamorphic grade varies from green-schist facies to lower-amphibolite facies. Contacts between pegmatite and country rock are sharp and parallel to the metamorphic foliation, suggesting a late-kinematic emplacement. Microthermometric measurements of fluid inclusions in quartz reveal an early complex CO2-H 2O-NaCl fluid. Inclusions are distributed in groups or in intragranular trails, and are interpreted as primary or pseudosecondary. The salinity is generally 0-7 wt% NaCl-eq., but rare high-salinity inclusions (29-32 wt% NaCl-eq.) were possibly originated in a magmatic stage. Homogenization temperatures (into liquid or vapor, occasionally critical) range from 227 to 346°C. The fluid inclusion pressures at the homogenization points (minimal trapping pressures) vary between 1500 and 2700 bars. A low salinity aqueous fluid was trapped in secondary inclusions with homogenization temperatures (into liquid) of 210-264°C, and densities of 0.76-0.85 g/cm3. At lower temperature (103 a 183°C), a late fracturing originated secondary fluid inclusions, which contain low salinity water (0-5wt% NaCl-eq.). The wide variation in cavity morphology, the large variation of CO 2 proportion and the total homogenization temperatures indicate immiscibility of an early complex fluid, with fluid inclusions reaching up to 100% of CO2 due to the leakage of the aqueous fluid, induced by deformation of the country rock. Occasionally, a recrystallization event trapped part of the aqueous fluid. © 2003 Asociación Geológica Argentina.

Registro:

Documento: Artículo
Título:Fluid inclusions in Sn-bearing pegmatites of the Sierra de San Luis, Argentina
Autor:Montenegro, T.; Sosa, G.M.
Filiación:Universidad de Buenos Aires, CONICET, Departamento de Geología, Pabellón 2, C1428EHA Buenos Aires, Argentina
Departamento de Geología, Facultad de Cie. Fisico-Matemat./Nat, Universidad Nacional de San Luis, Chacabuco y Padernera 5700 San Luis, Argentina
Palabras clave:CO2; Fluid inclusions; Pegmatite; Tin; fluid composition; fluid inclusion; fractional crystallization; Ordovician; pegmatite; tin; Argentina; San Luis; Sierra de San Luis; South America; Western Hemisphere; World
Año:2003
Volumen:58
Número:3
Página de inicio:347
Página de fin:355
Título revista:Revista de la Asociacion Geologica Argentina
Título revista abreviado:Rev. Asoc. Geol. Argent.
ISSN:00044822
Registro:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00044822_v58_n3_p347_Montenegro

Referencias:

  • Acenolaza, F.G., Toselli, A.J., Consideraciones estratigráficas y tectónicas sobre el Paleozoico inferior del Noroeste Argentino (1973) 2° Congreso Latinoamericano de Geología Caracas, Venezuela, Actas, 2, pp. 755-763
  • Bowers, T.S., Helgeson, H.C., Calculation of the thermodynamic and geochemical consequences of nonideal mixing in the system H2O-CO2-NaCl on phase relations in geologic systems: Metamorphic equilibria at high pressures and temperatures (1983) American Mineralogist, 68, pp. 159-1075
  • Bozzo, A.T., Chen, J.R., Barduhn, A.J., The properties of the hydrates of chlorine and carbon dioxide (1973) 4th International Symposium of Fresh Water from the Sea, 3, pp. 437-451. , A. Delyannis y E. Delyannis, Ed
  • Brown, P.E., FLINCOR: A microcomputer program for the reduction and investigation of fluid-inclusion data (1989) American Mineralogist, 74, pp. 1390-1393
  • Catalano, L.R., Nueva zona estañífera de la República Argentina (1929) Revista Minera, 1, pp. 19-21. , Buenos Aires
  • Černý, P., Rare-element granitic pegmatites. Part 1: Anatomy and internal evolution of pegmatite deposits (1991) Geoscience Canada, 81 (2), pp. 49-81
  • Galliski, M.A., La Provincia Pegmatítica Pampeana. I: Tipología y distribución de sus distritos económicos (1994) Revista de la Asociación Geológica Argentina, 49 (1-2), pp. 99-112
  • Galliski, M.A., La Provincia Pegmatítica Pampeana. II: Metalogénesis de sus distritos económicos (1994) Revista de la Asociación Geológica Argentina, 49 (1-2), pp. 113-122
  • Johnson, E.L., Hollister, L.S., Syndeformational fluid trapping in quartz: Determining the pressure-temperature conditions of deformation from fluid inclusions and the formation of pure CO2 fluid inclusions during grain-boundary migration (1995) Journal of Metamorphic Geology, 16, pp. 239-249
  • Llambías, E.J., Cingolani, C., Varela, R., Prozzi, C., Ortiz Suárez, A., Caminos, R., Toselli, A., Saavedra, J., Leucogranodioritas sincinemáticas ordovícicas en la Sierra de San Luis (1991) 6° Congreso Geológico Chileno, Viña Del Mar, Chile, pp. 187-191. , Resúmenes Expandidos
  • London, D., Internal differentiation of rare-element pegmatites; a synthesis of recent research (1990) Geological Society of America, pp. 35-50. , Special Paper 246
  • London, D., Morgan IV, G.B., Herving, R.L., Vapor-undersaturated experiments with Macusani glass + H2O at 200 Mpa, and the internal differentiation of granitic pegmatites (1989) Contributions to Mineralogy and Petrology, 102, pp. 1-17
  • Miyashiro, A., (1973) Metamorphism and Metamorphic Belts, p. 492. , George Allen and Unwin. London
  • Ortiz Suárez, A., Sosa, G., Relaciones genéticas entre las pegmatitas portadoras de estaño y las metamorfitas asociadas en la zona de La Carolina/San Francisco del Monte de Oro, Provincia de San Luis (1991) Revista de la Asociación Geológica Argentina, 46 (3-4), pp. 339-343
  • Ortiz Suárez, A., Prozzi, C., Llambías, E.J., Geología de la parte sur de la Sierra de San Luis y granitoides asociados, Argentina (1992) Revista de Estudios Geológicos, 48, pp. 269-277. , Madrid
  • Pagés, C., Informe preliminary de las Minas «Yolanda» e « Irene», Departamento San Martín, Provincia de San Luis (1947), Informe Dirección General de Fabricaciones Militares, Buenos Aires, (inédito); Potter, R., Clynne, M.A., Brown, D.L., Freezing point depression of aqueous sodium chloride solutions (1978) Economic Geology, 73, pp. 284-285
  • Schwartz, M.O., Oberthür, T., Amanor, J., Gyapong, W.A., Fluid inclusion re-equilibration and P-T-X constraints on fluid evolution in the Ashanti gold deposit, Ghana (1992) European Journal of Mineralogy, 4 (5), pp. 1017-1033
  • Sheperd, T.J., Alderton, D.H.M., Rankin, A.H., (1985) A Practical Guide to Fluid Inclusions Studies, p. 239. , Blackie and Sons, Glasgow
  • Sosa, G., Pegmatitas portadoras de estaño de la Provincia de San Luis, Argentina, su geología, mineralogía y génesis. I° Reunión de Mineralogía y Metalogenia y I° Jornada de Mineralogía, Petrografía y Metalogénesis de Rocas Ultrabásicas. La Plata, Argentina (1992) Actas, pp. 281-296
  • Sosa, G.M., Pegmatitas portadoras de estaño de la Provincia de San Luis, su' geología, mineralogía y génesis (1990), Tesis Doctoral. Universidad Nacional de San Luis; Sosa, G., Augsburger, M.S., Pedregosa, J.C., Columbite-group minerals from rare-metal granitic pegmatites of the Sierra de San Luis, Argentina (2002) European Journal of Mineralogy, 14 (3), pp. 627-636
  • Schwartz, M.O., Oberthür, T., Amanor, J., Gyapong, W.A., Fluid inclusion re-equilibration and P-T-X constraints on fluid evolution in the Ashanti gold deposit, Ghana (1992) European Journal of Mineralogy, 4, pp. 1017-1033
  • Thomas, A.V., Bray, C.J., Spooner, E.T.C., A discussion of the Jahns-Burnham proposal for the formation of zoned granitic pegmatites using solid-liquid-vapor inclusions from the Tanco pegmatite. S. E. Manitoba, Canada (1988) Royal Society of Edinburgh, Transactions, Earth Sciences, 79, pp. 299-315
  • Turner, J.C., Méndez, V., Geología del sector oriental de los departamentos de Santa Victoria e Iruya, provincia de Salta, República Argentina (1975) Academia Nacional de Ciencias, Boletín, 51, pp. 11-24. , Córdoba
  • Turner, J.C., Méndez, V., Puna (1979) Segundo Simposio de Geología Regional Argentina, pp. 13-56. , J. C. M. Turner, (ed.) Academia Nacional de Ciencias, Actas: Có rdoba
  • Urbina, N.E., Ulacco, H.J., Sosa, G.M., Ramos, G.A., Lacreu, H.L., Oggier, F.P., Aguilera, D., Guerstein, P.G., Metallogeny of the Sierras Pampeanas of San Luis, Argentina (2000) XVII Simposio Sobre la Geología de Latinoamérica, 83, pp. 1-6. , Stuttgart, Alemania. Profil Band 18, CD Archivo

Citas:

---------- APA ----------
Montenegro, T. & Sosa, G.M. (2003) . Fluid inclusions in Sn-bearing pegmatites of the Sierra de San Luis, Argentina . Revista de la Asociacion Geologica Argentina, 58(3), 347-355.
Recuperado de https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00044822_v58_n3_p347_Montenegro [ ]
---------- CHICAGO ----------
Montenegro, T., Sosa, G.M. "Fluid inclusions in Sn-bearing pegmatites of the Sierra de San Luis, Argentina " . Revista de la Asociacion Geologica Argentina 58, no. 3 (2003) : 347-355.
Recuperado de https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00044822_v58_n3_p347_Montenegro [ ]
---------- MLA ----------
Montenegro, T., Sosa, G.M. "Fluid inclusions in Sn-bearing pegmatites of the Sierra de San Luis, Argentina " . Revista de la Asociacion Geologica Argentina, vol. 58, no. 3, 2003, pp. 347-355.
Recuperado de https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00044822_v58_n3_p347_Montenegro [ ]
---------- VANCOUVER ----------
Montenegro, T., Sosa, G.M. Fluid inclusions in Sn-bearing pegmatites of the Sierra de San Luis, Argentina . Rev. Asoc. Geol. Argent. 2003;58(3):347-355.
Available from: https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00044822_v58_n3_p347_Montenegro [ ]