(they don't make them like they used to ... )
Cratons are anomalously-strong regions of the continents that have largely resisted tectonic forces for billions of years. How such strong zones could be forged in a hot, low-viscosity, low stress, early-Earth has been a long-standing puzzle for geologists. Adam Beall, Katie Cooper and I have recently proposed that cratons were made by the catastrophic switching on of plate tectonics. An event in which the stresses were larger than they have ever been in the intervening 3 billion years (Beall et al, 2018)
This is a companion discussion topic for the original entry at https://www.underworldcode.org/articles/craton-formation-and-the-onset-of-plate-tectonics/