Unraveling plate tectonics: From mantle plumes to subduction dynamics

Abstract

The origin and evolution of plate tectonics are essential for understanding Earth's habitability, intricately linked to deep mantle convection, core-mantle interactions, and mantle plumes. Despite substantial advancements in the field, critical gaps remain in our understanding of how these processes interrelate and influence Earth's evolutionary trajectory. This review provides a comprehensive synthesis of the evolutionary dynamics of plate tectonics, focusing on the mechanisms of subduction initiation and its effects on core-mantle boundary structures and mantle plume formation. Throughout Earth's geological history, from the late Hadean to the present, plate tectonics has undergone significant evolution, with a transition from early mantle plume control to present plate negative buoyancy mechanisms in subduction initiation. We highlight how subducting slabs drive mantle flow, modifying the properties and dynamics of the core-mantle boundary and influencing mantle composition, leading to seismic anisotropy and the emergence of mantle plumes. Our findings underscore that tectonic evolution is fundamentally tied to thermal processes, shifting from spontaneous cooling to externally driven mechanisms. We advocate for future research to clarify the changes in heat and material transfer between the core and lower mantle induced by subduction, as well as their implications for physical and chemical properties of the core-mantle boundary. Understanding these dynamics is crucial, as they directly affect surface tectonic activity, volcanic eruptions, and broader environmental changes, thereby advancing our knowledge of the Earth system's intricate relationships.