Tidal dissipation within Earth’s solidifying magma ocean: III. Effects of matrix compaction

Tidal dissipation in a solidifying magma ocean is crucial for understanding the early thermal and orbital evolution of the Earth–Moon system. This study examines how matrix compaction affects tidal dissipation during magma ocean solidification. Using a one-dimensional two-phase flow model, we simulate the evolution of melt fraction profiles under various mantle potential temperatures and grain sizes. Whereas matrix compaction generally lowers tidal dissipation by reducing the cumulate thickness, our results show that, during early solidification phases, it can enhance dissipation at high tide-raising frequencies by increasing the resonance frequency of the magma ocean. These findings underscore the importance of considering matrix compaction in tidal dissipation models and suggest a potentially more complex interplay between solidification dynamics and tidal response than previously understood. This work provides a framework that allows us to better explore the possible evolutionary paths of the early Earth–Moon system.