Pangaea
From Freepedia
Pangaea or Pangea (derived from Παγγαία, Greek for "all earth") is the name given to the supercontinent that existed during the Paleozoic and Mesozoic eras, before the process of plate tectonics separated the component continents into their current configuration. The name was coined by Alfred Wegener, chief proponent of Continental Drift in 1915.
The continents apparently first coalesced to form Pangaea about 300 mya (Million Years Ago), giving rise to several prominent mountain ranges by the process known as orogeny. Several of these ranges still exist, although they have become much lower by means of erosion. The Appalachians of eastern North America, the Atlas Mountains of North Africa, and the Urals of Eurasia are prime examples. The mantle under Pangaea's former location seemingly remained very hot even after coalescence, convection currents within the underlying magma pushing the centre of the supercontinent upward. As a result, the area that is now the continent of Africa was situated tens of meters higher than the surrounding continents.
In configuration, Pangaea was a C-shaped landmass that spread across the equator. The body of water that was enclosed within the resulting crescent has been named the Tethys Sea. Owing to Pangaea's massive size, the inland regions appear to have been very dry due to the lack of precipitation. The large supercontinent would potentially have allowed terrestrial animals to migrate freely all the way from the South Pole to the North Pole.
The vast ocean that once surrounded the supercontinent of Pangaea has been named Panthalassa. Pangaea, it seems, broke up about 180 mya in the Jurassic Period, firstly into two supercontinents (Gondwana to the south and Laurasia to the north), thereafter into the continents as we understand them today.
Pangaea was not the first supercontinent. From the evidence available, scientists reconstruct that a predecessor, termed Pannotia, formed about 600 mya, before dividing again some 50 million years later. Another, Rodinia, apparently formed approximately 1,100 mya and divided 750 mya.
