RT Journal Article
T1 Significance of MORB-derived Amphibolites from the Aracena Metamorphic Belt, Southwest Spain
A1 Castro Dorado, Antonio
A1 Fernández Rodríguez, Carlos
A1 Rosa Díaz, Jesús de la
A1 Moreno-Ventas Bravo, Ignacio
A1 Rogers, Graeme
AB The Aracena metamorphic belt, in the southwest IberianMassif, is characterized by the presence of MORB-derivedamphibolites and continental rocks deformed and metamorphosedduring the Hercynian orogeny. Geochemical relationshipsof these amphibolites indicate the existence of a multiplefractionation process from a set of parental magmas, implyingthe existence of a multi-chamber system beneath the ridge wherethe basalt protolith was extruded. Neodymium isotopic ratios aretypical of MORB, and oxygen isotopes indicate that theseamphibolites have been derived from the uppermost part of theoceanic crust Thermal evolution, revealed from the study ofchemical variations in the amphibole chemistry, is interpreted asresulting from subduction in a low-pressure regime in which thethermal structure of the continental hanging-wall played animportant role. This continental wall was previously heated bysubduction of a slab window resulting from migration of a triplejunction along the continental edge during plate convergence.Three petrologic arguments support this tectonic model Theseare: (1) the low-pressure inverted metamorphic gradient ofamphibolites of the oceanic domain; (2) the high-temperaturelow-pressure metamorphism of the continental hanging wall;(3) the early intrusion of boninites into the continental domain.
PB Oxford University Press
SN 1460-2415
YR 1996
FD 1996
LK http://hdl.handle.net/10272/6072
UL http://hdl.handle.net/10272/6072
LA eng
NO Castro Dorado, C., Fernández Rodríguez, C., Rosa  Díaz, J. de la, Moreno-Ventas Bravo, I.: "Significance of MORB-derived Amphibolites from the Aracena Metamorphic Belt, Southwest Spain". Journal of Petrology. Vol. 37, n. 2, p. 235-260 (1996). ISSN 1460-2415
DS Repositorio Institucional de la Universidad de Huelva
RD 30 may 2026