TY - JOUR
T1 - High-temperature creep of olivine single crystals
T2 - 1. Mechanical results for buffered samples
AU - Bai, Q.
AU - Mackwell, S. J.
AU - Kohlstedt, D. L.
PY - 1991
Y1 - 1991
N2 - To investigate the rheological behavior of the Earth's upper mantle, over 100 high-temperature deformation experiments have been performed on single crystals of San Carlos olivine in controlled chemical environments at a total pressure of 0.1 MPa. Constitutive equations have been determined which describe the dependence of creep rate on applied stress, temperature and oxygen fugacity in terms of power law relations. In addition, the effects of orthopyroxene activity and loading orientation on the creep behavior have been investigated. For samples of each of three compression directions, [110]c, [011]c and [110]c, buffered by orthopyroxene or magnesiowustite, either two or three power law equations are required to describe the dependence of strain rate at fixed stress on temperature and oxygen fugacity over the full range of experimental conditions. It is proposed that in each power law regime a different creep mechanism controls the creep rate. For all of the experimental conditions, the activation energy for creep is independent of the stress level and the stress exponent is constant at 3.5 ± 0.1. -from Authors
AB - To investigate the rheological behavior of the Earth's upper mantle, over 100 high-temperature deformation experiments have been performed on single crystals of San Carlos olivine in controlled chemical environments at a total pressure of 0.1 MPa. Constitutive equations have been determined which describe the dependence of creep rate on applied stress, temperature and oxygen fugacity in terms of power law relations. In addition, the effects of orthopyroxene activity and loading orientation on the creep behavior have been investigated. For samples of each of three compression directions, [110]c, [011]c and [110]c, buffered by orthopyroxene or magnesiowustite, either two or three power law equations are required to describe the dependence of strain rate at fixed stress on temperature and oxygen fugacity over the full range of experimental conditions. It is proposed that in each power law regime a different creep mechanism controls the creep rate. For all of the experimental conditions, the activation energy for creep is independent of the stress level and the stress exponent is constant at 3.5 ± 0.1. -from Authors
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U2 - 10.1029/90JB01723
DO - 10.1029/90JB01723
M3 - Article
AN - SCOPUS:0026005461
SN - 0148-0227
VL - 96
SP - 2441
EP - 2463
JO - Journal of Geophysical Research
JF - Journal of Geophysical Research
IS - B2
ER -