The question of when plate tectonics commenced on Earth has exercised geoscientists for decades. There are two schools of thought, one that argues that the process started from the time of the first geological record, some 3.8 Byr ago. The other school opts for a later date, perhaps around 3 Ga, perhaps later. The arguments advanced range from field observations, through petrological, structural and geochemical data, to geodynamical modelling. In this Great Debate, which is convened by EGU and AOGS, two teams will defend the alternative points of view.

Moderator: to be decided

Debaters:
Pro early plate tectonics
Jeroen van Hunen - Durham University
Nicholas Arndt – University Grenoble Alpes

Anti early plate tectonics
Peter Cawood – University St Andrews
Teras Gerya - ETH Zurich