Amazonian Craton

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"Brazilian shield" redirects here. For the highlands in eastern central and southern Brazil, see Brazilian Highlands.
Approximate location of Mesoproterozoic (older than 1.3 Ga) cratons in South America and Africa. The São Luís and the Luis Alves cratonic fragments (Brazil) are shown, but the Arequipa–Antofalla Craton, the Sahara Craton and some minor African cratons are not. Other versions describe the Guiana Shield separated from the Amazonian Shield by a depression.

The Amazonian Craton is a geologic province located in South America. It occupies a large portion of the central, north and eastern part of the continent. The Guiana Shield and Central Brazil Shield (Guaporé Shield) constitutes respectively the northern and southern exhumed parts of the craton. Between the two shields lies the Amazon Rift, a zone of weakness within the craton. Smaller cratons of Precambrian rocks south of the Amazonian Shield are the Río de la Plata Craton and the São Francisco Craton, which lies to the east.

It has been suggested that the Late MesoproterozoicEarly Neoproterozoic aged Sveconorwegian Orogen in Fennoscandia could have been caused by a continent–continent collision between the Amazonia and Baltica.[1] The question is open if Telemarkia terrane in Norway was derived from the Amazonian Craton but this possibility does not imply necessarily that there was a continental collision.[2]

The Río Apa Craton at the Paraguay-Brazil border is considered be likely just the southern part of the Amazonian Craton.[3] The rocks of Río Apa were deformed during the Sunsás orogeny.[4]

See also[edit]

References[edit]

  1. ^ Slagstad, Trond; Roberts, Nick M. W.; Markens, Rogens; Røhr, Torkil; Schiellerup, Henrik (2013). "A non-collisional, accretionary Sveconorwegian orogen". Terra Nova 25: 30–37. doi:10.1111/ter.12001. 
  2. ^ Bingen, Bernard; Nordgulen, Øystein; Viola, Giulio (2008). "A four-phase model for the Sveconorwegian orogeny, SW Scandinavia". Norwegian Journal of Geology 88: 43–72. 
  3. ^ Mantovani, Marta S.M.; de Brito Neves, Benjamin B. (2010). "The Paranapanema Lithospheric Block: Its Nature and Role in the Accretion of Gondwana". In Gaucher, Claudio; Sial, Alcides; Haverson, Galen. Neoproterozoic-Cambrian tectonics, global change and evolution: a focus on south western Gondwana. Elsevier. p. 258. doi:10.1016/S0166-2635(09)01619-3. 
  4. ^ 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: 267–270. doi:10.1130/G30510.1.