Reinterpreting Early Earth Tectonic Styles Through Planetary Heat Dissipation
Jian KuangThe tectonic evolution of the early Earth remains one of the most debated questions in Earth science. Geological observations and geodynamic modeling have greatly expanded the range of plausible tectonic regimes, including subduction-like processes, vertical tectonics, plume-related deformation, and transitional states. However, most previous studies have primarily focused on whether individual tectonic regimes are compatible with geological observations or dynamically feasible, whereas the physical mechanisms governing tectonic regime evolution remain incompletely understood. Here, I review recent advances in geological and geodynamic studies of early Earth tectonics and propose a complementary qualitative perspective based on planetary heat transport. Within this framework, secular changes in mantle temperature, radiogenic heat production, rheology, and lithospheric properties progressively modified the mechanisms responsible for planetary heat transport. Different tectonic regimes can therefore be viewed as distinct organizations of heat transport operating under different thermal states. This perspective provides a common physical basis for organizing diverse tectonic regimes in terms of heat transport and offers new insights into the links between planetary cooling, heat transport, and tectonic regime evolution. Finally, I outline future directions for translating this conceptual perspective into quantitative thermodynamic metrics and integrating numerical modeling with geological constraints to better understand Earth’s early tectonic evolution.