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Earth Evolution
Earth Materials
Proterozoic 2500 - 542 million years ago
The Onset of Plate Tectonics

The Proterozoic was the time when "modern" plate tectonic processes overtook the "plume-driven" processes of the Archean. Small Archean proto-continents with stable cratons collided along convergent plate boundaries forming mountain belts of high-pressure metamorphic rocks.

Eventually, a global assemblage of accreted continental landmasses led to the formation of the first supercontinents, Columbia (1800 million years ago) and Rodinia (1000 million years ago). These supercontinents subsequently rifted apart at divergent plate boundaries to form new oceans such as the Late Proterozoic Panthalassic Ocean.