The signature of inner core nucleation on the geodynamo

摘要: Abstract Energy considerations indicate that the power delivered to present-day geodynamo comes mainly from growth of solid inner core, through light element and latent heat releases. The nucleation core was, therefore, a major transition for geodynamo. Here, we use numerical dynamo simulations linked by thermochemical evolution investigate effects inner-core (ICN) on geodynamo, identify possible ICN footprints in palaeomagnetic field. Our results suggest strong-field dipole-dominated prior after (the uniformitarian scenario) is most likely. We predict little footprint surface field intensity, consistent with observed lack long-term trend paleointensity data. Instead, find best proxy an increase axial octupole strength age, ICN, which might be resolvable record. confirm existence weak-field, multipolar dynamos suggesting have transiently reached weak-field state catastrophic scenario). narrow stability domain these implies scenario less probable than scenario.