Biblioteca de la Universidad Complutense de Madrid

The San Blas Pluton: An example of Carboniferous plutonism in the Sierras Pampeanas, Argentina

Impacto



Dahlquist, Juan A. y Pankhurst, R.J. y Rapela, Carlos W. y Casquet, César y Fanning, C.M. y Alasino, Pablo H. y Baez, Miguel (2006) The San Blas Pluton: An example of Carboniferous plutonism in the Sierras Pampeanas, Argentina. Journal of South American earth sciences, 20 . pp. 341-350. ISSN 0895-9811

[img] PDF
10MB

URL Oficial: http://www.elsevier.com/locate/jsames



Resumen

New geochronological and geochemical data are reported for the San Blas Pluton (SBP), in the northwestern Sierra de Velasco, Sierras
Pampeanas, which intrudes Ordovician granitoids developed during the Famatinian orogeny. A precise Carboniferous age of 340±3 Ma is
established by U–Pb dating of zircon using a sensitive high-resolution ion microprobe (SHRIMP). The SBP illustrates several petrological and
geochemical characteristics of previously reported Carboniferous granitoids in the Sierras Pampeanas. Their generation is consistent with a
regional reheating of the crust at approximately 342 Ma, which resulted in the formation of relatively large amounts of granitic melts that were
emplaced in higher crustal levels along master fractures (older master shear zones of Lower Paleozoic age). The SBP can be chemically defined as
a typical A-type granitoid related to postcollisonal or postorogenic magmatism. Its high REE content and extraordinarily high U and Th
concentrations may have economic significance. Many previously published Devonian and Carboniferous K–Ar dates are reset Ordovician ages,
but the existence of other Carboniferous bodies in the Sierra de Velasco cannot be discounted until detailed mapping of the whole Sierra is
completed.


Tipo de documento:Artículo
Palabras clave:SHRIMP; San Blas Pluton; Sierra de Velasco; Carboniferous age; A-type granitoids; Postorogenic magmatism
Materias:Ciencias > Geología > Petrología
Código ID:11635
Depositado:23 Nov 2010 11:57
Última Modificación:01 Sep 2011 12:06

Sólo personal del repositorio: página de control del artículo