Closure of the Rheic Ocean

The Rheic Ocean, which opened during the Early Ordovician when ribbon terranes separated from Gondwana, closed approximately 340 million years ago as Gondwana and Laurussia collided. This closure produced the Variscan-Alleghenian-Ouachita mountain belts, with sutures stretching over 10,000 kilometers from present-day Mexico to Turkey. The collision drove the assembly of the supercontinent Pangaea and generated high-pressure metamorphism across the contact zone between the converging landmasses.