Skip to Main content Skip to Navigation
Journal articles

Pressure-temperature estimates of the lizardite/antigorite transition in high pressure serpentinites.

Abstract : Serpentine minerals in natural samples are dominated by lizardite and antigorite. In spite of numerous petrological experiments, the stability fields of these species remain poorly constrained. This paper presents the petrological observations and the Raman spectroscopy and XRD analyses of natural serpentinites from the Alpine paleo-accretionary wedge. Serpentine varieties are identified from a range of metamorphic pressure and temperature conditions from sub-greenschist (P < 4 kbar, T ~ 200-300°C) to eclogite facies conditions (P > 20 kbar, T > 460°C) along a subduction geothermal gradient. We used the observed mineral assemblage in natural serpentinite along with the Tmax estimated by Raman spectroscopy of the carbonaceous matter of the associated metasediments to constrain the temperature of the lizardite to antigorite transition at high pressures. We show that below 300°C, lizardite and locally chrysotile are the dominant species in the mesh texture. Between 320 and 390°C, lizardite is progressively replaced by antigorite at the grain boundaries through dissolution-precipitation processes in the presence of SiO2 enriched fluids and through a solid-state transition in the cores of the lizardite mesh. Above 390°C, under high-grade blueschist to eclogite facies conditions, antigorite is the sole stable serpentine mineral until the onset of secondary olivine crystallization at 460°C.
Document type :
Journal articles
Complete list of metadata

Cited literature [56 references]  Display  Hide  Download
Contributor : Stéphane Schwartz Connect in order to contact the contributor
Submitted on : Monday, August 26, 2013 - 3:05:02 PM
Last modification on : Wednesday, April 13, 2022 - 2:24:02 PM
Long-term archiving on: : Thursday, April 6, 2017 - 9:14:39 AM


Files produced by the author(s)



Stéphane Schwartz, Stéphane Guillot, Bruno Reynard, Romain Lafay, Baptiste Debret, et al.. Pressure-temperature estimates of the lizardite/antigorite transition in high pressure serpentinites.. Lithos, Elsevier, 2012, 178, pp.197-210. ⟨10.1016/j.lithos.2012.11.023⟩. ⟨insu-00854214⟩



Record views


Files downloads