Atlantica (; ''Atlantika'') is an ancient

continent A continent is any of several large geographical regions. Continents are generally identified by convention (norm), convention rather than any strict criteria. A continent could be a single large landmass, a part of a very large landmass, as ...

that formed during the

Proterozoic The Proterozoic ( ) is the third of the four geologic eons of Earth's history, spanning the time interval from 2500 to 538.8 Mya, and is the longest eon of Earth's geologic time scale. It is preceded by the Archean and followed by the Phanerozo ...

about (two billion years ago, Ga) from various 2 Ga

craton A craton ( , , or ; from "strength") is an old and stable part of the continental lithosphere, which consists of Earth's two topmost layers, the crust and the uppermost mantle. Having often survived cycles of merging and rifting of contine ...

s located in what are now

West Africa West Africa, also known as Western Africa, is the westernmost region of Africa. The United Nations geoscheme for Africa#Western Africa, United Nations defines Western Africa as the 16 countries of Benin, Burkina Faso, Cape Verde, The Gambia, Gha ...

and eastern

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 ...

. The name, introduced by John Rogers in 1996, was chosen because the parts of the ancient continent are now located on opposite sides of the

South Atlantic Ocean The Atlantic Ocean is the second largest of the world's five borders of the oceans, oceanic divisions, with an area of about . It covers approximately 17% of Earth#Surface, Earth's surface and about 24% of its water surface area. During the ...

Formation

Atlantica formed simultaneously with

Nena Gabriele Susanne Kerner (born 24 March 1960), better known by her stage name Nena, is a German singer who rose to international fame in 1983 as the lead vocalist of the band Nena (band), Nena with the Neue Deutsche Welle song "99 Luftballons". I ...

at about 1.9 Ga from Archaean cratons, including

Amazonia The Amazon rainforest, also called the Amazon jungle or Amazonia, is a moist broadleaf tropical rainforest in the Amazon biome that covers most of the Amazon basin of South America. This basin encompasses , of which are covered by the rainf ...

in present-day South America, and the Congo, West Africa and North Africa Cratons in Africa.

Breakup

Atlantica separated from Nena between 1.6–1.4 Ga when Columbia — a supercontinent composed of Ur, Nena, and Atlantica — fragmented. Atlantica and continents Nena and Ur and some minor plates formed the

supercontinent In geology, a supercontinent is the assembly of most or all of Earth's continent, continental blocks or cratons to form a single large landmass. However, some geologists use a different definition, "a grouping of formerly dispersed continents", ...

Rodinia Rodinia (from the Russian родина, ''rodina'', meaning "motherland, birthplace") was a Mesoproterozoic and Neoproterozoic supercontinent that assembled 1.26–0.90 billion years ago (Ga) and broke up 750–633 million years ago (Ma). wer ...

about 1 Ga ago. Between 1–0.5 Ga Rodinia split into three new continents:

Laurasia Laurasia () was the more northern of two large landmasses that formed part of the Pangaea supercontinent from around ( Mya), the other being Gondwana. It separated from Gondwana (beginning in the late Triassic period) during the breakup of Pa ...

and East and West

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 ...

; Atlantica became the nucleus of West Gondwana. During this later stage, the

Neoproterozoic The Neoproterozoic Era is the last of the three geologic eras of the Proterozoic geologic eon, eon, spanning from 1 billion to 538.8 million years ago, and is the last era of the Precambrian "supereon". It is preceded by the Mesoproterozoic era an ...

era, a Brasiliano-

Pan African Pan-Africanism is a nationalist movement that aims to encourage and strengthen bonds of solidarity between all indigenous peoples and diasporas of African ancestry. Based on a common goal dating back to the Atlantic slave trade, the Trans-Sa ...

orogenic Orogeny () is a mountain-building process that takes place at a convergent plate margin when plate motion compresses the margin. An or develops as the compressed plate crumples and is uplifted to form one or more mountain ranges. This involv ...

system developed. The central part of this system, the

Araçuaí Araçuaí () is a Brazilian Municipalities of Brazil, municipality located in the northeast of the state of Minas Gerais in the Jequitinhonha River valley. The Araçuaí River, a tributary of the Jequitinhonha, flows through it. Its population wa ...

-West Congo

orogen An orogenic belt, orogen, or mobile belt, is a zone of Earth's crust affected by orogeny. An orogenic belt develops when a continental plate crumples and is uplifted to form one or more mountain ranges; this involves a series of geological proc ...

, has left a distinct pattern of deformations, still present on both sides of the Atlantic Ocean.

Notes

References

* * * * * {{Continents of the world Historical continents Proterozoic History of the Atlantic Ocean

Formation

Breakup

See also

Notes

References