' Ocean-Plate Tectonics 'is a mode of mantle convection characterised by the autonomous relative movement of multiple discrete, mostly rigid, portions of oceanic plates at the surface, driven and maintained principally by subducted parts of these same plates that are sinking gravitationally back into Earth’s interior and deforming the mantle interior in the process. - Crameri et al. (2018)
As distinguished from other less specific, less integral concepts:
' Plate Tectonics ' is the horizontal relative movement of several discrete and mostly-rigid surface-plate segments (Hess, 1962).
' Continental Drift ' is the horizontal relative movement of discrete continental plates (Wegener, 1912).
Figure from Crameri et al. (2018): The dynamic life of an oceanic plate. A schematic highlighting the ocean- plate formation, cooling and destruction as part of the planet’s global mantle convection driven by the temperature gradient between its hot deep interior and the cold surface environment. Ocean-Plate Tectonics is the concept that describes not only the horizontal surface motion of the oceanic plate (grey arrow), but also highlights the pull from its subducted portion as the main driver (blue arrow), distinguishes the oceanic plate (dark brown) from its continental counterpart, acknowledges the plate–mantle coupling that induces characteristic regional mantle-flow patterns (black flow lines), and describes the dynamics of the oceanic plate as part of the larger framework of global mantle convection that transports heat out of the interior (light-red arrow).