Universidad Complutense de Madrid
E-Prints Complutense

Metamorphic evolution of anthophyllite/cummingtonite-cordierite rocks from the upper unit of the Ordenes Complex (Galicia, NW Spain)

Impacto

Descargas

Último año



Abati Gómez, Jacobo y Arenas Martín, Ricardo (2005) Metamorphic evolution of anthophyllite/cummingtonite-cordierite rocks from the upper unit of the Ordenes Complex (Galicia, NW Spain). European Journal of Mineralogy, 17 . pp. 57-68. ISSN ISSN 0935-1221, e-ISSN 1617-4011

[img] PDF
Restringido a Sólo personal autorizado del repositorio

9MB

URL Oficial: http://eurjmin.geoscienceworld.org/content/17/1/57




Resumen

Two types of low-Ca amphibolites are described for the first time in the Ordenes Complex (Galicia, NW Spain). The first type exhibits an initial mineral assemblage containing sillimanite, staurolite and anthophyllite, which are found as microinclusions in cordierite crystals. This association indicates medium pressure and temperatures above 600ºC, and is replaced in the matrix by a medium to low-pressure assemblage of anthophyllite, cordierite and garnet. The second type is represented by lowpressure amphibolitic gneisses formed mainly of cummingtonite, cordierite, andalusite and garnet. The first type of amphibolite would appear to give rise to the second type as a result of metamorphic evolution to lower pressures . A fragment of the decompressive P-T path was obtained by a detailed study of the mineral assemblage succession and the textural relationships of these rocks. The P-T path begins with an almost isothermal decompression from ca. 6-7 kbar and 650ºC. This kind of P-T path (isothermal) is usually interpreted, according to thermal models, as originating during exhumation favoured by some tectonic process. Hence, the exhumation of the uppermost unit of the Ordenes Complex, in which the anthophyllite-cummingtonite rocks are located, appears to have been facilitated by some kind of extensional tectonic process.


Tipo de documento:Artículo
Palabras clave:Metamorphic evolution, Anthophyllite, Cummingtonite, Cordierite, Low-Ca amphibolites, Ordenes Complex, NW Spain.
Materias:Ciencias > Geología > Petrología
Código ID:43395
Depositado:02 Aug 2017 08:13
Última Modificación:02 Aug 2017 08:13

Descargas en el último año

Sólo personal del repositorio: página de control del artículo