Plastic flow of oriented single crystals of olivine: 1. Mechanical data

Abstract

A total of 41 selectively oriented single crystals of olivine (Fo92) were deformed under uniaxial stresses of 100–1800 bars in the temperature range 1150°–1600°C. Under uniform stress no strain inhomogeneities were observed. For all orientations both strain rate and dislocation structure stabilized after 1–2% strain and remained stable to the highest strains achieved (40%). For all orientations, creep could be represented by a power law of the form = Aσ3.6 where A varied with orientation by a factor of 50. Shape change and crystallographic rotation data for some orientations could only be accounted for by a substantial dislocation climb contribution to the strain rate. All specimens were decorated to show the dislocation structure. Supplement is available with entire article on microfiche. Order from American Geophysical Union, 1909 K Street, N.W., Washington, D.C. 20006. Document J77-009. Payment must accompany order.