Pangaea

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Map of Pangaea
Pangaea with latitude longitude overlay (black lines) . (220 million years ago.)
Location of the different branches of the Caledonian/Acadian belts at the end of the Caledonian orogeny (Early Devonian). Present day coastlines are indicated in grey for reference. Later in geological history, the Atlantic Ocean opened and the different parts of the orogenic belt moved apart.[1]

Pangaea [2] was the global supercontinent which formed in the Palaeozoic era. The process started about 450 million years ago (mya), and was complete by 210 mya.

Pangea was the latest of a series of global supercontinents. They have formed at various times since plate tectonics began on Earth.

Formation[change | change source]

The collisions between continental plates formed the greatest mountain ranges in the history of the Phanerozoic eon.[3] The mountain building included the Caledonian orogeny and the Alleghenian orogeny. The low mountains of Scotland, Scandinavia and eastern North America are the ground-down remains of these vast events.[4]

Break-up[change | change source]

There were three major phases in the break-up of Pangaea.

Pangaea broke up about 180/200 million years ago, in the early middle Jurassic. It broke into supercontinents Laurasia and Gondwana before each of these broke into the current continents. One rift resulted in a new ocean, the North Atlantic Ocean.[5]

The second major phase in the break-up of Pangaea began in the Lower Cretaceous (150–140 Ma), when Gondwana separated into multiple continents (Africa, South America, India, Antarctica, and Australia).[5]

The third major and final phase of the break-up of Pangaea occurred in the early Cenozoic (Paleocene to Oligocene). Laurasia split when North America/Greenland (also called Laurentia) broke free from Eurasia, opening the Norwegian Sea about 60–55 Ma. The Atlantic and Indian Oceans continued to expand, closing the Tethys Ocean.

The break-up of Pangaea continues today in the Great Rift Valley.

Other sources[change | change source]

  • Matte P. 2001. The Variscan collage and orogeny (480-290 Ma) and the tectonic definition of the Armorica microplate: a review. Terra Nova 13, 122-128.
  • Stampfli G.M.; Raumer J.F. von & Borel G.D. 2002. Paleozoic evolution of pre-Variscan terranes: from Gondwana to the Variscan collision. Geological Society of America Special Paper 364, pp. 263-280.
  • Torsvik T.H.; Smethurst M.A.; Meert J.G.; Van der Voo R.; McKerrow W.S.; Brasier M.D.; Sturt B.A. & Walderhaug H.J. 1996. Continental break-up and collision in the Neoproterozoic and Palaeozoic - a tale of Baltica and Laurentia. Earth-Science Reviews 40, pp. 229-258.
  • Ziegler P.A. 1990. Geological Atlas of Western and Central Europe. 2nd ed, Shell Internationale Petroleum Maatschappij B.V. ISBN 90-6644-125-9

References[change | change source]

  1. Reconstruction based on Matte (2001); Stampfli et al. (2002); Torsvik et al. (1996) and Ziegler (1990)
  2. meaning entire Earth in Ancient Greek
  3. Cocks L.R.M. & Torsvik T.H. 2006. European geography in a global context from the Vendian to the end of the Palaeozoic in: Gee D.G. & Stephenson R.A. (eds) European lithosphere dynamics, Geological Society of London Memoirs 32, pp. 83–95.
  4. Stanley, Steven 1998. Earth system history. pp355–359
  5. 5.0 5.1 Zeeya Merali, Brian J. Skinner Visualizing Earth Science. Wiley. ISBN 978-0470-41847-5