In geology, orogeny is the process of mountain building. An orogenic belt, therefore, is a geologic structure associated with continental collisions and mountain building. Generally orogenic belts consist of long parallel strips of rock exhibiting similar characteristics along the length of the belt. The details of the specific belt will vary with what collided and the details of the collision. Frequently, many of the rock formations involved in the collision (Orogeny) will be severely deformed and metamorphosed. During this process, deeply buried rocks may be pushed to the surface. Sea bottom and near shore material may be overthrust into the orogeny covering some or all of the active area. Someplace under the orogenic belt will be a subduction zone that promoted the collision by consuming crust and dragging the material on one side of the collision into contact with that on the other. The subduction zone may have volcanoes or lava flows associated with it.

List of orogenies

North American orogenies

• Acadian orogeny
  • Eastern U.S. during Silurian and Devonian Periods.
• Antler orogeny
  • Ancestral Sierra Nevada western United States.
• Appalachian orogeny
  • Appalachian Mountains, is a well studied orogenic belt resulting from a late Paleozoic collision between North America and Africa.
• Grenville orogeny
  • Eastern North America from Newfoundland to North Carolina during Late Proterozoic Eon 1800 - ~1100 Myr ago.
• Laramide orogeny
  • Rocky Mountains, western North America, 40-70 Myr ago.
• Nevadan orogeny
  • developed along western North America during the Jurassic Period.
• Ouachita orogeny
  • Ouachita Mountains of Arkansas and Oklahoma is an orogenic belt that dates from the late Paleozoic Era and is most likely a continuation of the Appalachian orogeny west across the Mississippi embayment - Reelfoot Rift zone.
• Penokean orogeny
  • Wisconsin, Minnesota, and Michigan, U. S. A. and southern Ontario, Canada, 1900 Myr ago.
• Taconic orogeny
  • NE U.S. and Canada during the Ordovician Period.

European orogenies

• Alpine orogeny
  • Formation of the Alps during Eocene through Miocene Periods.
• Caledonian orogeny
  • Between Europe and Greenland in the Silurian Period.
• Carpathean orogeny
  • Carpathian Mountains of east Europe during the Miocene Period.
• Hellenic orogeny
  • Greece and Aegean area during Eocene through Miocene Period.
• Ural orogeny
  • Ural Mountains, Eurasia during the Permian Period.
• Variscan orogeny
  • Western Europe, Iberia, and SW England early to mid - Paleozoic Era.

Asian orogenies

• The Aravalli-Delhi Orogen (precambrian)
• The Cimmerian and Cathayasian orogenies
  • Active through Triassic and Jurassic Periods along south and southeast Asia.
• Himalayan orogeny
  • The Himalaya Mountains is a result of the ongoing collision of the Indian Plate with the Eurasian Plate.

South American orogenies

• Andean orogeny
  • Andes Mountains, 0-200 Myr ago.

Antarctic orogenies

• Napier orogeny (4000 ± 200 Myr ago.)
• Rayner orogeny (~ 3500 Myr ago.)
• Humboldt orogeny (~ 3000 Myr ago.)
• Insel orogeny (2650 ± 150 Myr ago.)
• Early Ruker orogeny (2000 - 1700 Myr ago.)
• Late Ruker / Nimrod orogeny (1000 ± 150 Myr ago.)
• Beardmore orogeny (633 - 620 Myr ago.)
• Ross Orogeny (~ 500 Myr ago.)

External links

• Maps of the Acadian and Taconic orogenies (http://greenfield.fortunecity.com/shell/89/)
• Antarctic Geology (http://home.freeuk.com/gtlloyd/tam/geochron.htm)