Energetically expensive dynamo action in Earth's basal magma ocean.

ABSTRACT: Previous studies focusing on the electrical conductivity and thermal evolution of an early magma ocean at the base of Earth's mantle have found that basal magma ocean (BMO) convection could have produced the ancient geomagnetic field. By advances in high-resolution dynamo modeling, we find that convection in a thin BMO-like spherical shell is able to sustain strong magnetic fields, including axial dipolar fields similar to current day field structure. However, integrating our dynamo results with improved thermal evolution models and taking the planet's rapid rotation into account using rotating convective turbulence models implies that an Earth-like magnetic field was unlikely to have been generated in the BMO, a finding relevant to the interpretation of ancient paleomagnetic signatures, E

SUBMITTER: Schaeffer N 

PROVIDER: S-EPMC12625979 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature