Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (29) Citing Articles via Google Scholar Google Scholar Articles by COUVY, H. Articles by CORDIER, P. Search for Related Content GeoRef GeoRef Citation

Shear deformation experiments of forsterite at 11 GPa - 1400°C in the multianvil apparatus

¹ Bayerisches Geoinstitut, Universität Bayreuth, Germany
² Laboratoire de Structure et Propriétés de l'Etat Solide, UMR CNRS 8008, Université des Sciences et Technologies de Lille, Villeneuve d'Ascq, France
³ Department of General Physics, Eötvös University Budapest, H-1445 Múzeum krt. 6-8, Budapest VIII, P.O.B. 323, Hungary

^* E-mail: presently at: Lunar and Planetary Institute, 3600 Bay Area Blvd, Houston, TX 77058-1113, USA

^** Patrick.Cordier{at}univ-lillel.fr

Synthetic forsterite samples were shear-deformed at 11 GPa, 1400°C in the multianvil apparatus. The deformation microstructures have been characterised by SEM, EBSD, X-ray diffraction peak broadening and strain anisotropy analysis, and TEM. Different time durations have been characterised with a view to follow the evolution of strain and stress in high-pressure deformation experiments. A high density of [001] dislocations is introduced during pressurization at room temperature although no significant macroscopic shear or crystal preferred orientations are induced at this stage. The deviatoric stress is probably on the order of 1.5 GPa. Heating at 1400°C leads to a rapid decrease of the density of these dislocations. The shear deformation at high-temperature leads to measurable strain and development of crystal preferred orientations after one hour. Stress and strain-rate continue to decrease with time, such that eight hour experiments exhibit microstructures where recovery is apparent. At this stage, the stress level is estimated at ca. 100 MPa from dislocation density measurements. Crystal preferred orientations and TEM characterisation show that glide of [001] dislocations on (100) or (010) is the dominant deformation mechanism. Further investigation is needed to determine whether inhibition of [100] glide in these experiments is due to the role of water or whether a physical effect of pressure is also contributing.

Key-words: shear deformation, high-pressure, forsterite, dislocations, core structure.

This article has been cited by other articles:

				S.-i. Karato and D. J. Weidner Laboratory Studies of the Rheological Properties of Minerals under Deep-Mantle Conditions Elements, June 1, 2008; 4(3): 191 - 196. [Abstract] [Full Text] [PDF]

				J. Durinck, P. Carrez, and P. Cordier Application of the Peierls-Nabarro model to dislocations in forsterite European Journal of Mineralogy, October 1, 2007; 19(5): 631 - 639. [Abstract] [Full Text] [PDF]

				P. Raterron, J. Chen, L. Li, D. Weidner, and P. Cordier Pressure-induced slip-system transition in forsterite: Single-crystal rheological properties at mantle pressure and temperature American Mineralogist, August 1, 2007; 92(8-9): 1436 - 1445. [Abstract] [Full Text] [PDF]

				L. LI, D. WEIDNER, P. RATERRON, J. CHEN, M. VAUGHAN, S. MEI, and B. DURHAM Deformation of olivine at mantle pressure using the D-DIA European Journal of Mineralogy, February 1, 2006; 18(1): 7 - 19. [Abstract] [Full Text] [PDF]

				I. Katayama, S.-i. Karato, and M. Brandon Evidence of high water content in the deep upper mantle inferred from deformation microstructures Geology, July 1, 2005; 33(7): 613 - 616. [Abstract] [Full Text] [PDF]