Low electrical conductivity of dry CaSiO3 perovskite under lower mantle conditions
Abstract
Electrical conductivity (EC) provides important constraints on the composition and volatile distribution of Earth's deep mantle, yet the EC of davemaoite (CaSiO3 perovskite), a major lower-mantle phase, remains poorly constrained. We measured the EC of nominally dry CaSiO3 perovskite at pressures up to 89 GPa and temperatures up to 2200 K using impedance spectroscopy in a laser-heated diamond anvil cell. Conductivity increases with temperature but decreases systematically with pressure and it is substantially lower than previously reported, yet broadly consistent with recent theoretical predictions for oxygen-vacancy-mediated ionic transport. A distinct change in the temperature dependence coincides with the tetragonal-to-cubic phase boundary, revealing a modest enhancement of ionic transport across the structural transition. Along a normal lower-mantle geotherm, dry davemaoite is comparable in conductivity to bridgmanite near the top of the lower mantle but becomes progressively less conductive with depth. Under cold-slab conditions, dry davemaoite is substantially less conductive than dry subducted MORB and cannot account for the observed high-conductivity anomalies. Dry davemaoite therefore contributes little to bulk lower-mantle conductivity.
Related
- Reconstructing the spatiotemporal distribution of microbial-induced carbonate precipitation using electrical conductivity tomography
- Remote effect of anisotropy in electrical conductivity or magnetic permeability on dynamo action
- Relationship between soil electrical conductivity and water content: A multiscale petrophysical calibration
- Overestimation of meltwater fractions due to temperature bias in electrical conductivity-based hydrograph separation models in the Himalayas
- Van der Waals interactions in supercritical water under Earth's mantle conditions
BibTeX
@misc{okuda2026electrical,
title = {{Low electrical conductivity of dry CaSiO3 perovskite under lower mantle conditions}},
author = {Yoshiyuki Okuda and Bin Chen and Juliana Peckenpaugh and Hirokazu Kadobayashi},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.04499},
eprint = {2609.04499},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.04499},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - UNPB
TI - Low electrical conductivity of dry CaSiO3 perovskite under lower mantle conditions
AU - Yoshiyuki Okuda
AU - Bin Chen
AU - Juliana Peckenpaugh
AU - Hirokazu Kadobayashi
PY - 2026
DA - 2026/09/03
PB - arXiv
DO - 10.48550/arxiv.2609.04499
UR - https://arxiv.org/abs/2609.04499
AB - Electrical conductivity (EC) provides important constraints on the composition and volatile distribution of Earth's deep mantle, yet the EC of davemaoite (CaSiO3 perovskite), a major lower-mantle phase, remains poorly constrained. We measured the EC of nominally dry CaSiO3 perovskite at pressures up to 89 GPa and temperatures up to 2200 K using impedance spectroscopy in a laser-heated diamond anvil cell. Conductivity increases with temperature but decreases systematically with pressure and it is substantially lower than previously reported, yet broadly consistent with recent theoretical predictions for oxygen-vacancy-mediated ionic transport. A distinct change in the temperature dependence coincides with the tetragonal-to-cubic phase boundary, revealing a modest enhancement of ionic transport across the structural transition. Along a normal lower-mantle geotherm, dry davemaoite is comparable in conductivity to bridgmanite near the top of the lower mantle but becomes progressively less conductive with depth. Under cold-slab conditions, dry davemaoite is substantially less conductive than dry subducted MORB and cannot account for the observed high-conductivity anomalies. Dry davemaoite therefore contributes little to bulk lower-mantle conductivity.
ER -