Diffusion Creep in Perovskite: Implications for the Rheology of the Lower Mantle
- 6 March 1992
- journal article
- other
- Published by American Association for the Advancement of Science (AAAS) in Science
- Vol. 255 (5049) , 1238-1240
- https://doi.org/10.1126/science.255.5049.1238
Abstract
High-temperature creep experiments on polycrystalline perovskite (CaTiO 3 ), an analog of (Mg,Fe)SiO 3 perovskite of the lower mantle, suggest that (grain size-sensitive) diffusion creep is important in the lower mantle and show that creep rate is enhanced by the transformation from the orthorhombic to the tetragonal structure. These observations suggest that grain-size reduction after a subducting slab passes through the 670-kilometer discontinuity or after a phase transformation from orthorhombic to tetragonal in perovskite will result in rheological softening in the top portions of the lower mantle.Keywords
This publication has 23 references indexed in Scilit:
- Superplastic flow in finegrained limestonePublished by Elsevier ,2003
- Synthesis and crystal-chemical characterization of MgSiO3 perovskitePublished by Elsevier ,2002
- Aseismicity in the lower mantle by superplasticity of the descending slabNature, 1991
- Diffusion creep in feldspar aggregates: experimental evidenceJournal of Structural Geology, 1991
- Plasticity of MGSIO3 perovskite: The results of microhardness tests on single crystalsGeophysical Research Letters, 1990
- Electrical conductivity of the lower mantle: a molecular dynamics simulation of MgSiO3 perovskitePhysics of the Earth and Planetary Interiors, 1989
- Plasticity-crystal structure systematics in dense oxides and its implications for the creep strength of the Earth's deep interior: a preliminary resultPhysics of the Earth and Planetary Interiors, 1989
- The role of recrystallization in the preferred orientation of olivinePhysics of the Earth and Planetary Interiors, 1988
- Grain-size distribution and rheology of the upper mantleTectonophysics, 1984
- Rheology of the upper mantle: Inferences from peridotite xenolithsTectonophysics, 1980