During this period, two supercontinents emerged: Rodinia, which formed approximately 1.2 billion years ago and broke apart about 750 million years ago, and Pangaea, which formed around 335 million ...
In 1912 he proposed that the continents we know today were once all attached in a single landmass he called Pangaea (Greek for "all earth"). They were surrounded by one global ocean, but then ...
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