Thermal Evolution of Planetary Interiors With a Crystallizing Basal Magma Ocean Coupled to Parameterized Mantle Convection

Basal magma oceans (BMOs) persisting in the silicate portion of terrestrial planets for long periods of time (1 Gyr) offer the potential to reconcile unexplained contradictions between geochemical and geophysical observations, yet our knowledge of how the presence of such layers influence planetary evolution is far from mature. In this study, we produce 1D thermal evolution models using parameterized convection for Earth and Venus‐like planets with consideration of a long‐lived BMO. In these models, we independently vary initial conditions and material properties of the system which are shown to have strong control on the thermal evolution of the system and associated crystallization rate of the BMO. We find small variations in viscosity prefactors, lower mantle activation volume, or melt depression of the liquid melting curve to have significant impact on the solid‐liquid interface and temperature evolution of the system. Similarly, small variations in initial conditions produces a shift in comparable Earth and Venus models. In general, we observe the thermal boundary layer between the solid and liquid mantle layers governs the coupling of the system and therefore its evolution. These parameterized models demonstrate the capability to better understand impact of individual parameters and coupling of interior layers, which drive the thermal evolution for both Earth and Venus cases.