Atlantica is the name given to an ancient continent
A continent is one of several very large landmasses on Earth. They are generally identified by convention rather than any strict criteria, with seven regions commonly regarded as continents—they are : Asia, Africa, North America, South America, Antarctica, Europe, and Australia.Plate tectonics is...

 that formed during the Proterozoic
The Proterozoic is a geological eon representing a period before the first abundant complex life on Earth. The name Proterozoic comes from the Greek "earlier life"...

 about (two billion years ago, Ga) from various 2 Ga craton
A craton is an old and stable part of the continental lithosphere. Having often survived cycles of merging and rifting of continents, cratons are generally found in the interiors of tectonic plates. They are characteristically composed of ancient crystalline basement rock, which may be covered by...

s located in what is now West Africa
West Africa
West Africa or Western Africa is the westernmost region of the African continent. Geopolitically, the UN definition of Western Africa includes the following 16 countries and an area of approximately 5 million square km:-Flags of West Africa:...

 and eastern South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...


The name, introduced by , was chosen because the continent opened up to form the South Atlantic Ocean.


According to , Atlantica formed simultaneously with Nena
Nena (supercontinent)
Nena was an ancient minor supercontinent that consisted of the cratons of Arctica, Baltica, and East Antarctica. Forming about 1.8 billion years ago, the continent was part of the global supercontinent, Columbia. Nena is an acronym that derives from Northern Europe and North...

 at about 1.9 Ga from Archaean cratons, including Amazonia in present-day South America, and the Congo, West Africa and North Africa Cratons in Africa.


Atlantica separated from Nena between 1.6–1.4 Ga when Columbia
Columbia (supercontinent)
Columbia, also known as Nuna and Hudsonland, was one of Earth's oldest supercontinents. It was first proposed by J.J.W. Rogers and M. Santosh and is thought to have existed approximately 1.8 to 1.5 billion years ago in the Paleoproterozoic Era. Zhao et al...

 — a supercontinent composed of Ur
Ur (continent)
Ur was a supercontinent that formed in the early Archean eon; the oldest continent on Earth, half a billion years older than Arctica. Ur joined with the continents Nena and Atlantica about to form the supercontinent Rodinia...

, Arctica
Arctica was an ancient continent which formed approximately 2.5 billion years ago in the Neoarchean era.Arctica consisted of the Canadian and Siberian shields, and is now roughly situated in the Arctic around the current North Pole.- History :...

, Nena, and Atlantica — fragmented.
Together with continents Nena and Ur and some minor plates, Atlantica formed the supercontinent
In geology, a supercontinent is a landmass comprising more than one continental core, or craton. The assembly of cratons and accreted terranes that form Eurasia qualifies as a supercontinent today.-History:...

In geology, Rodinia is the name of a supercontinent, a continent which contained most or all of Earth's landmass. According to plate tectonic reconstructions, Rodinia existed between 1.1 billion and 750 million years ago, in the Neoproterozoic era...

 about 1 Ga ago. The rifting of Rodinia between 1–0.5 Ga resulted in the formation of three new continents: Laurasia
In paleogeography, Laurasia was the northernmost of two supercontinents that formed part of the Pangaea supercontinent from approximately...

 and East and West Gondwana
In paleogeography, Gondwana , originally Gondwanaland, was the southernmost of two supercontinents that later became parts of the Pangaea supercontinent. It existed from approximately 510 to 180 million years ago . Gondwana is believed to have sutured between ca. 570 and 510 Mya,...

, of which Atlantica became the nucleus of the latter.

During this later stage, the Neoproterozoic
The Neoproterozoic Era is the unit of geologic time from 1,000 to 542.0 ± 1.0 million years ago. The terminal Era of the formal Proterozoic Eon , it is further subdivided into the Tonian, Cryogenian, and Ediacaran Periods...

 era, a Brasiliano-Pan African orogenic
Orogeny refers to forces and events leading to a severe structural deformation of the Earth's crust due to the engagement of tectonic plates. Response to such engagement results in the formation of long tracts of highly deformed rock called orogens or orogenic belts...

 system developed. The central part of this system, the Araçuaí
Araçuaí is a Brazilian municipality located in the northeast of the state of Minas Gerais in the Jequitinhonha River valley. The Araçuaí River, a tribuatary of the Jequitinhonha, flows through it.. Its population as of 2007 was estimated to be 36,083 people living in a total area of 2,235 km²....

-West Congo orogen, has left a distinct pattern of deformations, still present on both sides of the Atlantic.
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