Publication Date:
2000-11-25
Description:
High-pressure and high-temperature torsion experiments on olivine aggregates in dislocation creep show about 15 to 20% strain weakening before steady-state behavior, characterized by subgrain-rotation recrystallization and a strong lattice preferred orientation. Such weakening may provide a way to focus flow in the upper mantle without a change in deformation mechanism. Flow laws derived from low strain data may not be appropriate for use in modeling high strain regions. In such areas, seismic wave propagation will be anisotropic with an axis of approximate rotational symmetry about the shear direction. In contrast to current thinking, the anisotropy will not indicate the orientation of the shear plane in highly strained, recrystallized olivine-rich rocks.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Bystricky, M -- Kunze, K -- Burlini, L -- Burg, J -- New York, N.Y. -- Science. 2000 Nov 24;290(5496):1564-7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Geologisches Institut, ETH-Zentrum, 8092 Zurich, Switzerland. misha@erdw.ethz.ch〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11090352" target="_blank"〉PubMed〈/a〉
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
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Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
