Model of Cortical Mosaics (MMC): An Auto-Organized Evolutionary Trajectory from the Primitive Crust to Proto-Plates

Francisco Javier Barros Lara

The structure and dynamics of Earth’s crust during the Hadean–Eoarchean remain one of the central challenges in geodynamics. Traditional models describe early states in terms of discrete regimes—stagnant lid, heat-pipe, episodic tectonics, or proto-plates—but none provides a continuous framework linking primitive fragmentation with the late emergence of plate tectonics.
This work proposes the Model of Cortical Mosaics (MMC), a conceptual framework that interprets the early crust as a self-organized system composed of cortical islets separated by thermally active boundaries and decoupled by an underlying warm matrix. Segmentation, continual reorganization, and hierarchical domain growth emerge from the interaction of initial heterogeneity, strong thermal gradients, local feedbacks, and frequent external forcing.
As Earth cools, the mosaic matures: the number of active boundaries decreases, larger domains consolidate, and coherent lateral mobility develops, setting the stage for localized foundering and plate-like behavior. Under this perspective, modern plate tectonics is not an independent regime but the advanced phase of the natural evolution of the cortical mosaic.
The MMC produces qualitative predictions testable in the Archean record, including persistent isotopic heterogeneity, domain hierarchies within cratons, deep relict discontinuities, marked variability in crustal thickness, and potential rotations or overturning of cortical islets. These signals allow evaluation of the model through reasonable falsification criteria compatible with the fragmentary nature of the early record.
The MMC thus provides a unified, physically motivated, and evolutionary framework that integrates disparate processes and offers a continuous narrative for interpreting the transition from Earth’s fragmented primitive crust to the establishment of plate tectonics.