This talk reviews sedimentary, igneous and metamorphic proxies along with paleomagnetic data to infer both the development of rigid lithospheric plates and their independent relative motion, and conclude that significant changes in Earth behaviour occurred in the mid- to late Archean, between 3.2 Ga and 2.5 Ga.

These changes in the behaviour and character of the lithosphere are consistent with a gestational transition from a non-plate tectonic mode, arguably with localized subduction, to the onset of sustained plate tectonics.