Brasiliano orogeny or Brasiliano cycle (Portuguese: Orogênese Brasiliana and Ciclo Brasiliano) refers to a series of orogenies from the Neoproterozoic era, exposed chiefly in Brazil but also in other parts of South America. The Brasiliano orogeny is a regional name for the larger Pan-African/Brasiliano orogeny that extended not only in South America but across most of Gondwana.[1] In a wide sense the Brasiliano orogeny includes also the Pampean orogeny. Almeida et al. coined the term Brasiliano Orogenic Cycle in 1973. The orogeny led to the closure of several oceans and aulacogens including the Adamastor Ocean, the Goianides Ocean, the Puncoviscana Ocean[note 1] and the Peri-Franciscano Ocean.[4]

West Gondwana with major cratons in brown and Pan-African orogenies in grey

Attempts to correlate the South American Brasiliano belts with the African Pan-African belts on the other side of the Atlantic have in many cases been problematic.[5]

Belts and belt provinces

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Name Modern location Nearby cratons Associated closed ocean Details
Apiaí Belt Southeast Brazil, South Brazil
Araçuaí Belt (Portuguese: Faixa Araçuaí) Northeast Brazil, Southeast Brazil São Francisco Craton[2] The Araçuaí Belt is the western portion of an orogen that included the West Congo orogen. The rifting and opening of the South Atlantic Ocean divided this orogen into an African and a South American part. The Araçuaí Belt lies east of the São Francisco Craton and northeast of the Brasilia and Ribeira belts.[6]
Borborema Province Northeastern Brazil The Borborema Province is a geologic province in Northeastern Brazil that contains various Brasiliano orogeny belts. The Borborema Province lies between the São Francisco Craton and the São Luis Craton. The African counterpart and continuation of these belts lies between the Congo Craton and the West African Craton.[7]
Brasilia Belt Northeastern Brazil, Southeastern Brazil São Francisco Craton, Paranapanema block[2]
Dom Feliciano Belt Southern Brazil, Eastern Uruguay Río de la Plata Craton Brazilides Ocean The Dom Feliciano Belt is an orogenic belt in Southern Brazil and Eastern Uruguay. It has been suggested that the Damara Belt in Southern Africa formed the eastern part of the belt before the South Atlantic rifted. The belt contains the remnants of a volcanic arc that possibly was the result of the subduction of the Adamastor Ocean lithosphere or of lithosphere from a tectonic plate west of the belt. The Dom Feliciano Belt distinctly lacks high temperature metamorphic rocks or evidence for a suture.[5]
Pampean Orogen Argentina Río de la Plata Craton[2] Pampean Ocean[2]
Paraguai Belt Central-West Brazil Amazonian Craton, São Francisco Craton, Paranapanema block, Río de la Plata Craton[2] Brazilides Ocean[2] The Paraguai Belt is surrounded by the Amazonian, São Francisco and Río de la Plata cratons. Its oroclinal bend is probably indebted to the irregular shape of the Amazonian Craton. The formation of the Paraguai belt is associated with the closure of the Clymene Ocean. The belt has a similar age of deformation as the Pampean orogen further south in Argentina.[8]
Riacho do Pontal Belt Northeastern Brazil
Ribeira Belt (Portuguese: Faixa Ribeira) Southeastern Brazil São Francisco Craton, Paranapanema block, Luís Alves Craton[2] Brazilides Ocean The Ribeira Belt is a deeply eroded orogen in Southeastern Brazil. The Ribeira Belt resulted from the collision of two continents. Most of the orogenic deformation occurred 590 to 563 million years ago.[9]
Rio Paraná Belt Central-West Brazil
Rio Pardo Belt Northeastern Brazil
Rio Preto Belt Northeastern Brazil
Sergipano Belt Northeastern Brazil São Francisco Craton[2] The Sergipano Belt lies northeast of the São Francisco Craton. The metamorphism of the rocks of the belt reaches the amphibolite facies.[10]

See also

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Notes

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  1. ^ This ocean is also called the Pampean Ocean.[2] The relationship of this ocean and the Puncoviscana Formation is disputed.[3]

References

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  1. ^ Kröner, A.; Stern, R. J. (2004). "Pan-African Orogeny". In Selley, R. C.; Cocks, R.; Plimer, I. (eds.). Encyclopedia of Geology. Vol. 1. Amsterdam: Elsevier. p. 1. ISBN 9780126363807. Retrieved 31 December 2015.
  2. ^ a b c d e f g h i Gaucher, Claudio; Frimmel, Hartwig E.; Germs, J.B. (2010). "Tectonic Events and Palaeogeographic Evolution of Southwestern Gondwana in the Neoproterozoic and Cambrian". In Gaucher, Claudio; Sial, Alcides; Haverson, Galen (eds.). Neoproterozoic-cambrian tectonics, global change and evolution: a focus on south western Gondwana. Elsevier. pp. 295–316.
  3. ^ Aceñolaza, Florencio G.; Toselli, Alejandro (2010). "The Pampean Orogen: Ediacaran-Lower Cambrian Evolutionary History of Central and Northwest Region of Argentina". In Gaucher, Claudio; Sial, Alcides; Haverson, Galen (eds.). Neoproterozoic-cambrian tectonics, global change and evolution: a focus on south western Gondwana. Elsevier. pp. 239–254.
  4. ^ de Brito Neves, Benjamin Bley. "Ciclos Transamazônico e Brasiliano" (PDF). Glossário Geológico Ilustrado (in Portuguese). Archived from the original (PDF) on 2018-11-26. Retrieved 2016-01-18.
  5. ^ a b Frimmel, Hartwig E. (2010). "Configuration of Pan-African Orogenic Belts in Southwestern Africa". In Gaucher, Claudio; Sial, Alcides; Haverson, Galen (eds.). Neoproterozoic-cambrian tectonics, global change and evolution: a focus on south western Gondwana. Elsevier. pp. 145–151.
  6. ^ Peres, Gilherme G.; Alkimim, Fernando F.; Jordt-Evangelista, Hanna (2004). "The southern Araçuaí belt and the Dom Silvério Group: geologic architecture and tectonic significance" (PDF). Anais da Academia Brasileira de Ciências. 76 (4): 771–790. doi:10.1590/S0001-37652004000400011.
  7. ^ dos Santos, Edilton José; Van Schmus, William Randall; Kozuch, Marianne; de Brito Neves, Benjamim Bley (2010). "The Cariris Velhos tectonic event in Northeast Brazil". Journal of South American Earth Sciences. 29: 61–76. doi:10.1016/j.jsames.2009.07.003.
  8. ^ Tohver, E.; Trindade, R.I.F.; Solum, G.F.; Hall, C.M.; Riccomini, C.; Nogueira, A.C. (2010). "Closing the Clymene ocean and bending a Brasiliano belt: Evidence for the Cambrian formation of Gondwana, southeast Amazon craton". Geology. 38 (3): 267–270. doi:10.1130/G30510.1.
  9. ^ Heilbron, Monica; De Morisson Valeriano, Cláudio; Sayão, Cláudia Valladares; Machado, Nuno (1995). "A orogênese brasiliana no segmento central da Faixa Ribeira, Brasil". Revista Brasileira de Geociências (in Portuguese). 25 (4): 249–266. doi:10.25249/0375-7536.1996249266. Archived from the original on 11 March 2016. Retrieved 16 January 2016.
  10. ^ Caby, R.; Sial, A.N.; Arthaud, M.; Vauchez, A. (1991). "Crustal Evolution and the Brasiliano Orogeny in Northeast Brazil". In Dallmeyer, R.D.; Lécorché, J.P. (eds.). The West African Orogens and Circum-Atlantic Correlatives. pp. 374–397. ISBN 978-3-642-84155-2.