Original paper
Zoned garnets in the northern Dora-Maira Massif and their contribution to a reconstruction of the regional metamorphic evolution
Sandrone, Riccardo; Borghi, Alessandro
European Journal of Mineralogy Volume 4 Number 3 (1992), p. 465 - 474
33 references
published: Jun 4, 1992
manuscript accepted: Nov 21, 1991
manuscript received: Apr 17, 1991
DOI: 10.1127/ejm/4/3/0465
Abstract
Abstract Three garnet generations are recognizable in the metapelites of the Dora-Maira polymetamorphic basement, often coexisting at the single-specimen scale or as strikingly zoned single blasts. This observation offers further evidence for a pre-Alpine history of the Massif, as well as providing new information on the meso-Alpine metamorphic event and the P-T path of its northern part. This trajectory is characterized by two metamorphic peaks at the same temperature, but at different pressures, reflecting two distinct thermal gradients and geodynamic environments. The first (eo-Alpine event) is related to type-B subduction, whereas the second (meso-Alpine event) is linked to continental collision
Keywords
garnet • Alpine metamorphism • P-T path • Dora-Maira Massif • Western Alps