Measuring dislocation creep in diamond anvil cells
Abstract
Dislocation creep is a major mechanism of viscoelastic flow of rocks but it's examination in experiments under the conditions of the Earth's deeper mantle is challenging. Current techniques correlate measured plastic aggregate deformation with dislocation slip systems observed after recovery. While this works well in many cases, it must fail wherever post recovery examination of dislocations is impossible such as for non-recoverable or barely metastable phases. We present a technique of direct observation of dislocation creep under high pressure and of determination of the active slip systems. The technique is based on an assembly of piston- and sample crystals within the diamond cell sample chamber, on quantitative assessment of temporal evolution of lattice strain in individual sample crystallites, and on modeling of dislocation slip systems based on Laue diffraction peak profiles.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2013
- Bibcode:
- 2013AGUFMMR31A2266T
- Keywords:
-
- 3994 MINERAL PHYSICS Instruments and techniques;
- 3902 MINERAL PHYSICS Creep and deformation;
- 3924 MINERAL PHYSICS High-pressure behavior;
- 3954 MINERAL PHYSICS X-ray;
- neutron;
- and electron spectroscopy and diffraction