Electron back-scattering diffraction (EBSD) measurements of antigorite lattice-preferred orientations (LPO) - Archive ouverte HAL Access content directly
Journal Articles Journal of Microscopy Year : 2010

Electron back-scattering diffraction (EBSD) measurements of antigorite lattice-preferred orientations (LPO)

(1) , (1) , (2) , (1)
1
2
Lucile Bezacier
  • Function : Author
  • PersonId : 765484
  • IdRef : 153274999
G. Trullenque
Bruno Reynard

Abstract

Lattice preferred orientations of serpentines induce a strong anisotropy of various properties in serpentine bearing-rocks. Lattice preferred orientations had so far been obtained only by X-ray diffraction techniques. We have applied electron back-scattering diffraction to the measurement of the lattice preferred orientations of antigorite in a naturally deformed high-pressure serpentinite. This technique is very sensitive to sample preparation that can lead to surface amorphization in the case of serpentine. A polishing procedure is described that avoids amorphization and allows accurate electron back-scattering diffraction measurements with optimized experimental conditions in a variable pressure scanning electron microscope. Results indicate that deformation leads to lattice preferred orientations characterized by extremely strong c-axis clustering perpendicular to the foliation, as expected for a layered silicate. In the foliation plane, a significant clustering of the a-axis is observed and tentatively attributed to intracrystalline deformation mechanisms. These data suggest that antigorite deforms mostly by gliding along the basal plane of the layered phyllosilicate structure, but that gliding may occur along directions favouring a-axis alignment. Electron back-scattering diffraction appears to be a reliable method for determining phyllosilicate lattice preferred orientations in deformed rocks, with potential applications for determining anisotropy of properties like seismic velocities or thermal and electrical conductivities.
Not file

Dates and versions

insu-00681393 , version 1 (21-03-2012)

Identifiers

Cite

Bertrand van de Moortèle, Lucile Bezacier, G. Trullenque, Bruno Reynard. Electron back-scattering diffraction (EBSD) measurements of antigorite lattice-preferred orientations (LPO). Journal of Microscopy, 2010, 239 (3), pp.245-248. ⟨10.1111/j.1365-2818.2010.03398.x⟩. ⟨insu-00681393⟩
21 View
0 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More