The lattice thermal conductivity (κlat) of lower mantle (LM) minerals is a key physical quantity for understanding the dynamics and thermal history of the Earth’s deep interior. I, Haruhiko Dekura, from the Theoretical Mineral Physics Group (TMPG) at the Geophysical Research Center, Ehime University, have been vigorously advancing first-principles research on the κlat of Earth’s minerals for over a decade in collaboration with Prof. Taku Tsuchiya (Director). Based on our extensive research experiences, we were invited to contribute a review paper on the recent progress in the study of κlat of LM minerals. In this paper, we provide a comprehensive review of theoretical and experimental studies on the major LM minerals (MgO, MgSiO₃ bridgmanite (Brg) and post-perovskite (PPv)), and include a comparison of various theoretical calculation methods alongside experimental findings. We also give an overview of ab initio anharmonic lattice dynamics techniques developed in TMPG to compute κlat. The paper highlights the relative magnitude of κlat among these end-member LM phases (Fig. 1) and the effects of iron solid solution on the κlat. Previously under-discussed effects such as isotopic mass difference and higher-order crystal anharmonicity are also summarized in detail. Additionally, we describe current problems and future research directions for the thermal transport properties of the deep mantle (Haruhiko Dekura).
Recent progress in the study on phonon heat transport property of Earth’s lower mantle minerals. Haruhiko Dekura and Taku Tsuchiya, Journal of Physics: Condensed Matter, 36, 413005 (Topical Review), doi: 10.1088/1361-648X/ad5b46