Thermal structure of a fossil subduction wedge in the western Alps - Archive ouverte HAL Access content directly
Journal Articles Terra Nova Year : 2009

Thermal structure of a fossil subduction wedge in the western Alps

(1) , (2) , (3) , (3) , (2)
1
2
3

Abstract

New peak metamorphic temperatures are obtained by Raman spectroscopy of Carbonaceous Material to document the thermal structure of the central Western Alps with high sampling resolution. We show that peak metamorphic T gradually increases eastward from <330 to 350 °C (ultra-Dauphinois to subbriançonnais units), ∼350 to more than 400 °C (Briançonnais domain including the Zone Houillère where metamorphic index minerals are rare) and from 350 to more than 500 °C (Liguro-Piemontese domain). Combined with other constraints on the metamorphic evolution, this dataset reveals a good preservation of the overall thermal structure of the fossil subduction wedge, with no particular thermal overprint during collision. However, local confrontation with P-T estimates and radiometric ages reveals more subtle variations within tectonic units and across the main contacts that are linked to the past activity of the major thrusts and extensional shear zones during subduction and exhumation.
Not file

Dates and versions

hal-00401168 , version 1 (02-07-2009)

Identifiers

Cite

Sunsearé Gabalda, O. Beyssac, Laurent Jolivet, Philippe Agard, C. Chopin. Thermal structure of a fossil subduction wedge in the western Alps. Terra Nova, 2009, pp.28-34. ⟨10.1111/j.1365-3121.2008.00849.x⟩. ⟨hal-00401168⟩
89 View
0 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More