The Trans Brazilian Lineament (TBL), or Transbrasiliano Lineament, is a major

shear zone In geology, a shear zone is a thin zone within the Earth's crust or upper mantle that has been strongly deformed, due to the walls of rock on either side of the zone slipping past each other. In the upper crust, where rock is brittle, the shear ...

that developed in the

Precambrian The Precambrian ( ; or pre-Cambrian, sometimes abbreviated pC, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of t ...

period, and that has been reactivated several times since then, mostly recently during the

Mesozoic The Mesozoic Era is the Era (geology), era of Earth's Geologic time scale, geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceous Period (geology), Periods. It is characterized by the dominance of archosaurian r ...

. Movement along the shear zone helps explain how the

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

n continent could have fitted tightly to the

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

n continent before the breakup of

Gondwana Gondwana ( ; ) was a large landmass, sometimes referred to as a supercontinent. The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia (continent), Australia, Zea ...

Formation and location

The TBL was formed when the

Goiás Ocean Goiás () is a Brazilian States of Brazil, state located in the Central-West Region, Brazil, Central-West region. Goiás borders the Federal District (Brazil), Federal District and the states of (from north clockwise) Tocantins, Bahia, Minas Ge ...

, lying between the Amazonian craton and the Congo /

Sao Francisco craton SAO or Sao may refer to: Places * Sao civilisation, in Middle Africa from 6th century BC to 16th century AD * Sao, a town in Boussé Department, Burkina Faso * Serb Autonomous Regions (''Srpska autonomna oblast'', SAO), during the breakup of ...

, was closed during the formation of West Gondwana around 600 million years ago. The

lineament ''See also Line (geometry)'' A lineament is a linear feature in a landscape which is an expression of an underlying geological structure such as a fault. Typically a lineament will appear as a fault-aligned valley, a series of fault or fold-align ...

extends from the northeast coast of

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

in a southwesterly direction through

Paraguay Paraguay, officially the Republic of Paraguay, is a landlocked country in South America. It is bordered by Argentina to the Argentina–Paraguay border, south and southwest, Brazil to the Brazil–Paraguay border, east and northeast, and Boli ...

and into

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

, where it is dissipated in the Salado and Colorado extension basins. The Trans-Saharan Belt (TSB), running from

Algeria Algeria, officially the People's Democratic Republic of Algeria, is a country in the Maghreb region of North Africa. It is bordered to Algeria–Tunisia border, the northeast by Tunisia; to Algeria–Libya border, the east by Libya; to Alger ...

Benin Benin, officially the Republic of Benin, is a country in West Africa. It was formerly known as Dahomey. It is bordered by Togo to the west, Nigeria to the east, Burkina Faso to the north-west, and Niger to the north-east. The majority of its po ...

, was created in the same period. It marks the line where the

Pharusian Ocean The Pharusian Ocean (; ) is an ancient ocean that existed on Earth from , between the break-up of the Rodinia supercontinent and the start of formation of the Pannotia supercontinent. Opening and closure The Pharusian Ocean opened around 800 milli ...

, linked to the Goiás Ocean, was closed as 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., Li ...

collided with the

Saharan Metacraton The Saharan Metacraton is a large area of continental crust in the north-central part of Africa. Whereas a craton is an old and stable part of the lithosphere, the term "metacraton" is used to describe a craton that has been remobilized during an ...

. The TSB includes the Hoggar belt, which splays into the Kandi fault zone in Benin, corresponding to the

Sobral fault The Sobral fault is a major fault in the Borborema geological province of northeastern Brazil, a part of the Transbrasiliano lineament. It is commonly correlated with the Kandi fault in Benin, east of the West African craton. The fault lies in th ...

at the north of the TBL. Given the correspondence of faults, which is widely accepted, the TBL and TSB form perhaps the longest coherent shear zone on the Earth.

Gondwana breakup

Towards the north of the lineament in Brazil, a series of splay faults show where the crust has extended, and these faults match corresponding faults in Africa. Thus the Pernambuco fault in Brazil matches the Foumban fault zone in

Cameroon Cameroon, officially the Republic of Cameroon, is a country in Central Africa. It shares boundaries with Nigeria to the west and north, Chad to the northeast, the Central African Republic to the east, and Equatorial Guinea, Gabon, and the R ...

, and other Brazilian faults match the

Benue Trough The Benue Trough is a major geological structure underlying a large part of Nigeria and extending about 1,000 km northeast from the Bight of Benin to Lake Chad. It is part of the broader West and Central African Rift System. Location The ...

Nigeria Nigeria, officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf of Guinea in the Atlantic Ocean to the south. It covers an area of . With Demographics of Nigeria, ...

. The extension caused by these splay faults causes a poor fit between South America and Africa around the

Niger Delta The Niger Delta is the delta of the Niger River sitting directly on the Gulf of Guinea on the Atlantic Ocean in Nigeria. It is located within nine coastal southern Nigerian states, which include: all six states from the South South geopolitic ...

region. However, after allowing for a

sinistral Sinistral and dextral, in some scientific fields, are the two types of chirality ("handedness") or relative direction. The terms are derived from the Latin words for "left" (''sinister'') and "right" (''dexter''). Other disciplines use different ...

shear movement of about 100 km of the crust to the east of the TBL, there is an excellent fit between South America and Africa both to the south and the west of the Niger Delta.

References

{{Major South American geological formations Seismic faults of Brazil Geology of South America Precambrian South America