On the increase in thermal diffusivity caused by the perovskite to post-perovskite phase transition and its implications for mantle dynamics.
Earth and Planetary Science Letters
96 - 103.
The thermal diffusivity (κ) of perovskite and post-perovskite CaIrO3 has been measured, at elevated pressure and temperatures up to 600 °C, using the X-radiographic Ångström method. At high temperatures we find that the thermal diffusivity of post-perovskite is slightly below twice that of isochemical perovskite over the temperature range investigated. Assuming a similar effect occurs in MgSiO3 post-perovskite, the effect of the contrasting thermal transport properties between perovskite and post-perovskite on mantle dynamics has been investigated using simple two-dimensional convection models. These show a reduction in extent and increase in depth of post-perovskite lenses, as well as increased core–mantle-boundary heat-flux, broader upwellings and more vigorous downwellings when compared to the reference, constant a, case.
|Title:||On the increase in thermal diffusivity caused by the perovskite to post-perovskite phase transition and its implications for mantle dynamics|
|Open access status:||An open access version is available from UCL Discovery|
|Additional information:||This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.|
|Keywords:||D double-prime (D ''), Thermal diffusivity, Angstrom method, CaIrO3, Post-perovskite, Perovskite|
|UCL classification:||UCL > School of BEAMS > Faculty of Maths and Physical Sciences
UCL > School of BEAMS > Faculty of Maths and Physical Sciences > Chemistry
UCL > School of BEAMS > Faculty of Maths and Physical Sciences > Earth Sciences
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