Geologically young rocks laid down on the seafloor of the Pacific Ocean off the coast of New Zealand. This has revealed a fragment of the ancient deep seafloor, created some 3.3 billion years ago. We argue that the widely held view of the early Earth as a hotter place, free of earthquakes and with a surface so weak it was unable to form rigid plates is wrong. Instead, the young Earth was continually rocked by large earthquakes, triggered as one tectonic plate slid