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Antarctica Once Abutted Death Valley
Science News has a story of strange bedfellows. It seems that Antarctica was once adjacent to what is now the American Southwest, some 800 million years ago. Earth's continents then formed a supercontinent called Rodinia, predating Pangaea by some 550 million years. "...the ratios of neodymium isotopes in the ancient sediments in the Transantarctic Mountains are the same as those in what was then Laurentia, says Goodge. Also, the hafnium isotope ratios in the 1.44-billion-year-old zircons found in East Antarctica match those of the zircons found in the distinctive granites now found primarily in North America. Finally, the researchers note, the ratios of various isotopes and elements in a basketball-sized chunk of granite found in East Antarctica — a chunk ripped by a glacier from bedrock now smothered by thick ice, the team speculates — match those of granite found only in what was southwestern Laurentia, which today is the American Southwest."
The oldest one proposed is called Columbia, existing from 1.8 - 1.5 bya.
The next widely accepted was Rodinia, existing from 1.3 bya - 800 mya
The next possible was Pannotia, but it didn't last long, only from 600 - 550 mya.
The last one was Pangaea, from 250 mya to 150 mya.
The earliest ones are deduced mainly from paleomagnetism, so there may have been earlier supercontinents that we do not know about due to a lack of rocks that old.