The Maures–Tanneron Massif and the Corsica–Sardinia Block are two segments of the southern European Variscan belt that separated during the Late Oligocene–Miocene due to the opening of the Western Mediterranean basin. Correlation between the two regions, based mainly on petrologic similarities, is still debated. However, there are no detailed structural and petrochronological constraints on their potential relationships. In northern Sardinia there is well-documented evidence for a dextral transpressive shear zone that initiated after the first stage of frontal collision. In the Maures–Tanneron Massif, despite recognition of an important episode of transpressive deformation, it is still unclear which structures were active during this tectonic regime. We investigate in detail the kinematic of flow, finite strain and the timing of the deformation of the Cavalaire “Fault” (CF), a major ductile shear zone in the Maures–Tanneron Massif. In contrast to previous models, we argue that the CF is a transpressive shear zone characterized by a prevalent component of pure shear, while in-situ monazite geochronology reveals that the CF is initiated at ~ 323 Ma. The new data presented here, based on a multidisciplinary approach document, for the first time, the vorticity of the flow, finite strain and timing of this sector of the East Variscan Shear Zone, a regional-scale shear zone that characterized the Southern European Variscan belt during the late Carboniferous.

Timing and kinematics of flow in a transpressive dextral shear zone, Maures Massif (Southern France)

Simonetti M.
First
;
Carosi R.;Montomoli C.;Petroccia A.;Iaccarino S.
2020-01-01

Abstract

The Maures–Tanneron Massif and the Corsica–Sardinia Block are two segments of the southern European Variscan belt that separated during the Late Oligocene–Miocene due to the opening of the Western Mediterranean basin. Correlation between the two regions, based mainly on petrologic similarities, is still debated. However, there are no detailed structural and petrochronological constraints on their potential relationships. In northern Sardinia there is well-documented evidence for a dextral transpressive shear zone that initiated after the first stage of frontal collision. In the Maures–Tanneron Massif, despite recognition of an important episode of transpressive deformation, it is still unclear which structures were active during this tectonic regime. We investigate in detail the kinematic of flow, finite strain and the timing of the deformation of the Cavalaire “Fault” (CF), a major ductile shear zone in the Maures–Tanneron Massif. In contrast to previous models, we argue that the CF is a transpressive shear zone characterized by a prevalent component of pure shear, while in-situ monazite geochronology reveals that the CF is initiated at ~ 323 Ma. The new data presented here, based on a multidisciplinary approach document, for the first time, the vorticity of the flow, finite strain and timing of this sector of the East Variscan Shear Zone, a regional-scale shear zone that characterized the Southern European Variscan belt during the late Carboniferous.
2020
1
20
East variscan shear zone; Maures–Tanneron massif; Monazite petrochronology; Sardinian basement; Transpression; Vorticity
Simonetti M.; Carosi R.; Montomoli C.; Corsini M.; Petroccia A.; Cottle J.M.; Iaccarino S.
File in questo prodotto:
File Dimensione Formato  
Simonetti2020_Article_TimingAndKinematicsOfFlowInATr(2).pdf

Accesso riservato

Tipo di file: PDF EDITORIALE
Dimensione 10.05 MB
Formato Adobe PDF
10.05 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/1755375
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 25
  • ???jsp.display-item.citation.isi??? 24
social impact