Scientific publications

The change in the size of continental blocks and their number in the process of global supercontinental cycling is considered based on the analysis of published data. These changes were found to be towards an increase in the size of continental blocks involved in the assembly of supercontinents into megacontinents starting from the Early Archean, while their total number decreased. This process is associated with the thermal state of the mantle and the phases of the supercontinental cycle. The background for these changes was alternation of relatively hot and cold states of the mantle in the process of its general cooling. The explanation proposed by some researchers that the plate size increased gradually due to a change in tessellation (splitting of the sphere with a certain number of regular polygons) during the stage of disconnected continents in the settings of a relatively hot mantle and rapid and significant crust formation leading to supercontinent assembly is examined. During the assembled supercontinent stage, this increase slowed down due to the low rate of continental crust formation as the mantle was in a relatively cold state. The change in the size and number of plates during the supercontinental cycle was not a monotonous process, but had an episodic pattern, acquiring new features over time. Some frontiers of such updates appeared in the Archean with the rise of two types of supercontinental cycles, in the Early-Middle Proterozoic with the formation of a limited number of megacontinents, and in the Neoproterozoic Phanerozoic with the dominance of megacontinents up to tens of thousands of kilometers wide.