In Situ and Step-Heating ⁴⁰Ar/³⁹Ar Dating of White Mica in Low-Temperature Shear Zones (Tenda Massif, Alpine Corsica, France).

ABSTRACT: In order to clarify the link between ⁴⁰Ar/³⁹Ar record in white mica and deformation, we performed in situ and bulkwise ⁴⁰Ar/³⁹Ar dating over the East Tenda Shear Zone (Tenda massif, Alpine Corsica). White micas from 11 samples were selected and extensively analyzed using in situ techniques across nested scales of strain-intensity gradients developed at the expense of a late-Variscan protolith. ⁴⁰Ar/³⁹Ar systematics are unaffected by inherited Ar and directly linked to deformation with little or no Ar lattice (volume) diffusion. Extensive sampling allows constraining the end of deformation related to burial and exhumation, respectively, at ~34 and ~22 Ma, bracketing the duration of regional extensional shear to ~12 Myr. Resul

SUBMITTER: Beaudoin A 

PROVIDER: S-EPMC7756386 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature