Brasiliano orogeny or Brasiliano cycle ( pt, Orogênese Brasiliana and ''Ciclo Brasiliano'') refers to a series of orogenies of Neoproterozoic age exposed chiefly in

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

but also in other parts 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 southe ...

. 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 Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final stages ...

. In a wide sense the Brasiliano orogeny includes also the

Pampean orogeny The Pampean orogeny ( es, orogenia pampeana) was an orogeny active in the Cambrian in the western margin of the ancient landmass of Gondwana. The orogen's remains can now be observed in central Argentina, in particular at the Sierras de Córdob ...

. Almeida ''et al''. coined the term Brasiliano Orogenic Cycle in 1973. The orogeny led to the closure of several oceans and

aulacogen An aulacogen is a failed arm of a triple junction. Aulacogens are a part of plate tectonics where oceanic and continental crust is continuously being created, destroyed, and rearranged on the Earth’s surface. Specifically, aulacogens are a ri ...

s including the

Adamastor Ocean The Adamastor Ocean was a "proto-Atlantic" ocean that formed with the break-up of the Rodinia supercontinent 780-750 . It separated the Río de la Plata Craton from the Congo Craton. The inversion of the Adamastor Ocean began about 640 ...

, the Goianides Ocean, the Puncoviscana Ocean and the Peri-Franciscano Ocean. Attempts to correlate the South American Brasiliano belts with the African Pan-African belts on the other side of the Atlantic has in many cases been problematic.

Belts and belt provinces

}) ,

Northeast Brazil The Northeast Region of Brazil ( pt, Região Nordeste do Brasil; ) is one of the five official and political regions of the country according to the Brazilian Institute of Geography and Statistics. Of Brazil's twenty-six states, it comprises ni ...

Southeast Brazil The Southeast Region of Brazil ( pt, Região Sudeste do Brasil; ) is composed of the states of Espírito Santo, Minas Gerais, Rio de Janeiro (state), Rio de Janeiro and São Paulo State, São Paulo. It is the richest region of the country, responsi ...

São Francisco Craton The São Francisco Craton is an ancient craton in the eastern part of South America. The craton crops out in the Brazilian states of Minas Gerais and Bahia. It includes a number of blocks of Archean basement, separated by orogenic belts. The b ...

, , The Araçuaí Belt is the west portion of an orogen that included the West Congo orogen. The rifting and opening of the

South Atlantic The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe an ...

Ocean divided the orogen into an Africa and a South American part. The Araçuaí Belt lies east of the

and northeast of the Brasilia and Ribeira belts. , - bgcolor=#FFFFCC , Borborema Province ,

Northeastern Brazil The Northeast Region of Brazil ( pt, Região Nordeste do Brasil; ) is one of the five official and political regions of Brazil, regions of the country according to the Brazilian Institute of Geography and Statistics. Of Brazil's twenty-six state ...

, , , The Borborema Province is a geologic province in Northeastern Brazil that contains various Brasiliano orogeny belts. The Borborema Province lies between the

and the São Luis Craton. The belts African counterpart and continuation lies between the

Congo Craton The Congo Craton, covered by the Palaeozoic-to-recent Congo Basin, is an ancient Precambrian craton that with four others (the Kaapvaal, Zimbabwe, Tanzania, and West African cratons) makes up the modern continent of Africa. These cratons were fo ...

and the

West African Craton The West African Craton (WAC) is one of the five cratons of the Precambrian basement rock of Africa that make up the African Plate, the others being the Kalahari craton, Congo craton, Saharan Metacraton and Tanzania Craton.Jessell M.W., Liégeo ...

. , - bgcolor=#FFFFCC , Brasilia Belt ,

Southeastern Brazil The Southeast Region of Brazil ( pt, Região Sudeste do Brasil; ) is composed of the states of Espírito Santo, Minas Gerais, Rio de Janeiro (state), Rio de Janeiro and São Paulo State, São Paulo. It is the richest region of the country, responsi ...

Paranapanema block The Paranapanema block is a coherent block of lithosphere located in southeastern South America spanning roughly the same area as the Paraná Basin. The existence of a tectonically stable zone beneath the Paraná Basin was first suggested in 1975. ...

, , , - bgcolor=#FFFFCC , Dom Feliciano Belt , Southern Brazil, Eastern Uruguay ,

Río de la Plata Craton The Rio de la Plata Craton (RPC) is a medium-sized continental block found in Uruguay, eastern Argentina and southern Brazil. During its complex and protracted history it interacted with a series other blocks and is therefore considered importan ...

, Brazilides Ocean , The Dom Feliciano Belt is an orogenic belt in Southern Brazil and Eastern Uruguay. It has been suggested that the

Damara Belt The Damara orogeny was part of the Pan-African orogeny. The Damara orogeny occurred late in the creation of Gondwana, at the intersection of the Congo and the Kalahari cratons.; ; ; ; The Damara orogeny involved the suturing of the Congo– S� ...

in Southern Africa formed the eastern part of the belt before the South Atlantic rifted. The belt contains the remnants of a

volcanic arc A volcanic arc (also known as a magmatic arc) is a belt of volcanoes formed above a subducting oceanic tectonic plate, with the belt arranged in an arc shape as seen from above. Volcanic arcs typically parallel an oceanic trench, with the arc lo ...

that possibly was the result of the

subduction Subduction is a geological process in which the oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries. Where the oceanic lithosphere of a tectonic plate converges with the less dense lithosphere of a second plate, the ...

of the

lithosphere A lithosphere () is the rigid, outermost rocky shell of a terrestrial planet or natural satellite. On Earth, it is composed of the crust (geology), crust and the portion of the upper mantle (geology), mantle that behaves elastically on time sca ...

or of lithosphere from a tectonic plate west of the belt. The Dom Feliciano Belt distinctly lack high temperature

metamorphic rock Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock (protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, causin ...

s or evidence for a suture. , - bgcolor=#FFFFCC , Pampean Orogen ,

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 second-largest country in South America after Brazil, th ...

, Pampean Ocean , , - bgcolor=#FFFFCC , Paraguai Belt , Central-West Brazil ,

Amazonian Craton 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 and represents one of Earth's largest cratonic regions. The Guiana Shield and Central Braz ...

, Brazilides Ocean , The Paraguai Belt is surrounded by the Amazonian, São Francisco and

Río de la Plata The Río de la Plata (, "river of silver"), also called the River Plate or La Plata River in English, is the estuary formed by the confluence of the Uruguay River and the Paraná River at Punta Gorda. It empties into the Atlantic Ocean and fo ...

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 assimilate ages of deformation as the Pampean orogen further south in Argentina. , - bgcolor=#FFFFCC , Riacho do Pontal Belt ,

, , , , - bgcolor=#FFFFCC , Ribeira Belt ( pt, link=no, Faixa Ribeira) ,

, Luís Alves Craton , Brazilides Ocean , The Ribeira Belt is a deeply eroded orogen in

. The Ribeira Belt resulted from the collision of two continents. Most of the orogenic deformation occurred 590 to 563

million years ago The abbreviation Myr, "million years", is a unit of a quantity of (i.e. ) years, or 31.556926 teraseconds. Usage Myr (million years) is in common use in fields such as Earth science and cosmology. Myr is also used with Mya (million years ago). ...

. , - bgcolor=#FFFFCC , Rio Paraná Belt , Central-West Brazil , , , , - bgcolor=#FFFFCC , Rio Pardo Belt ,

, , , , - bgcolor=#FFFFCC , Rio Preto Belt ,

, , , , - bgcolor=#FFFFCC , Sergipano Belt ,

, , The Sergipano Belt lies northeast of the

. The

metamorphism Metamorphism is the transformation of existing rock (the protolith) to rock with a different mineral composition or texture. Metamorphism takes place at temperatures in excess of , and often also at elevated pressure or in the presence of chem ...

of the rocks of the belt reaches the

amphibolite facies Amphibolite () is a metamorphic rock that contains amphibole, especially hornblende and actinolite, as well as plagioclase feldspar, but with little or no quartz. It is typically dark-colored and dense, with a weakly foliated or schistose (flak ...

Notes

References

{{Major South American geological formations Orogenies of South America Cryogenian orogenies Ediacaran orogenies Ediacaran South America Geology of Argentina Geology of Brazil Geology of Paraguay Geology of Uruguay Neoproterozoic orogenies Neoproterozoic South America Precambrian South America

Belts and belt provinces

See also

Notes

References