An orocline — from the Greek words for "mountain" and "to bend" — is a bend or curvature of an orogenic (mountain building) belt imposed after it was formed. The term was introduced by S. Warren Carey in 1955 in a paper setting forth how complex shapes of various orogenic belts could be explained by actual bending, and that understanding this provided "the key to understanding the evolution of the continents". Carey showed that in a dozen cases where such bends were undone the results were substantially identical with continental reconstructions deduced by other means.. Recognition of oroclinal bending provided strong support to the subsequent theory of

plate tectonics Plate tectonics (from the la, label= Late Latin, tectonicus, from the grc, τεκτονικός, lit=pertaining to building) is the generally accepted scientific theory that considers the Earth's lithosphere to comprise a number of larg ...

Examples

South America - Blue Marble orthographic

*The Bolivian Orocline is a seaward concave bending in the coast of

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sou ...

and the

Andes The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...

mountains at about 18° S. At this point the orientation of the Andes turns from Northwest in

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = National seal , national_motto = "Firm and Happy f ...

to South in

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the eas ...

and

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the List of South American countries by area, second-largest ...

. The Andean segment north and south of the orocline have been rotated 15° to 20° counter clockwise and clockwise respectively. The orocline area overlaps with the area of maximum width of the Altiplano Plateau according to Isacks (1988) the orocline is related to crustal shortening. The specific point at 18° S where the coastline bends is known as the ''Arica Elbow''. *The Maipo Orocline or Maipo Transition Zone is an orocline located between 30° S and 38°S in the

with a break in trend at 33° S. *The Arauco Orocline a subtle orocline located at 37° S in south-central Chile. It marks a seaward-convex bend in the Andes. *Bothnian oroclines in the Svecofennian Domain in Finland and Sweden. *Inari orocline including the Lapland Granulite Belt in Finland, Norway and Russia. *Cantabrian Orocline, Spain *Lachlan Orocline, eastern Australia *Dabashan Orocline, China

Notes

References

External links

*{{Citation , first1= Rob , last1= Van der Voo , date= December 2004 , title= Paleomagnetism, Oroclines, and Growth of the Continental Crust , journal= GSA Today , volume= 14 , issue= 12 , pages= 4–9 , doi= 10.1130/1052-5173(2004)014<4:POAGOT>2.0.CO;2 , url= http://rock.geosociety.org/gsatoday/archive/14/12/pdf/i1052-5173-14-12-4.pdf , doi-access= free . Structural geology Orogeny

Examples

See also

Notes

References

External links