Plate tectonics: What, where, why, and when?

The theory of plate tectonics is widely accepted by scientists and provides a robust framework with which to describe predict the behavior Earth’s rigid outer shell – lithosphere in space time. Expressions tectonic interactions at surface also provide critical insight into machinations our planet’s inaccessible interior, allow postulation about geological characteristics other rocky bodies solar system beyond. Formalization this paradigm occurred landmark Penrose conference 1969, representing culmination centuries study, understanding “what”, “where”, “why”, “when” on Earth has continued improve since. In Centennial review, we summarize major discoveries that have been made these fields present modern-day holistic model for geodynamic evolution best accommodates key lines evidence its changes over Plate probably began global scale during Mesoarchean (c. 2.9–3.0 Ga), firm subduction older terranes accounted isolated ‘microcells’ initiated heads mantle plumes. Such early likely operated shallow angles was short-lived, owing buoyancy low rigidity hotter oceanic lithosphere. A transitional period Neoarchean Paleoproterozoic/Mesoproterozoic characterized secular cooling mantle, reduced increased strength, allowing angle convergent margins gradually steepen. appearance rocks Neoproterozoic 0.8–0.9 Ga) diagnostic do not mark onset tectonics, but simply record beginning modern-style cold, deep, steep an end-member state earlier, hotter, mobile lid regime.