Arctica, or Arctida
is a hypothetical 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 ...
which formed approximately 2.565
billion years ago
bya or b.y.a. is an abbreviation for " billion years ago". It is commonly used as a unit of time to denote length of time before the present in 109 years. This initialism is often used in the sciences of astronomy, geology, and paleontology.
The ...
in the
Neoarchean
The Neoarchean ( ; also spelled Neoarchaean) is the last geologic era in the Archean Eon that spans from 2800 to 2500 million years ago—the period being defined chronometrically and not referencing a specific level in a rock section on Ear ...
era. It was made of Archaean
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, including the
Siberian Craton
Siberia, also known as Siberian Craton, Angaraland (or simply Angara) and Angarida, is an ancient craton in the heart of Siberia. Today forming the Central Siberian Plateau, it formed an independent landmass prior to its fusion into Pangea during ...
, with its
Anabar Anabar may refer to:
* Anabar Bay, Laptev Sea
* Anabar Constituency, Nauru
* Anabar District, Nauru
* Anabar District, Russia, Sakha, Russia
* Anabar Highway, Russia
* Anabar Plateau, Russia
* Anabar (river)
The Anabar (, in its upper course ...
/
Aldan shield
Aldan Shield () is a shield in Siberia. It is an exposed basement of the Siberian Craton. Together with the Anabar Shield further to the northwest, the Aldan Shield is one of the main features of the craton.
The Aldan Shield geological region co ...
s in
Siberia
Siberia ( ; , ) is an extensive geographical region comprising all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has formed a part of the sovereign territory of Russia and its predecessor states ...
, and the
Slave
Slavery is the ownership of a person as property, especially in regards to their labour. Slavery typically involves compulsory work, with the slave's location of work and residence dictated by the party that holds them in bondage. Enslavemen ...
,
Wyoming
Wyoming ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States, Western United States. It borders Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho t ...
,
Superior
Superior may refer to:
*Superior (hierarchy), something which is higher in a hierarchical structure of any kind
Places
* Superior (proposed U.S. state), an unsuccessful proposal for the Upper Peninsula of Michigan to form a separate state
*Lak ...
, and
North Atlantic
The Atlantic Ocean is the second largest of the world's five oceanic divisions, with an area of about . It covers approximately 17% of Earth's surface and about 24% of its water surface area. During the Age of Discovery, it was known for ...
cratons in North America. Arctica was named by because the
Arctic Ocean
The Arctic Ocean is the smallest and shallowest of the world's five oceanic divisions. It spans an area of approximately and is the coldest of the world's oceans. The International Hydrographic Organization (IHO) recognizes it as an ocean, ...
formed by the separation of the
North American
North America is a continent in the Northern and Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Caribbean Sea, and to the sou ...
and
Siberian
Siberia ( ; , ) is an extensive geographical region comprising all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has formed a part of the sovereign territory of Russia and its predecessor states si ...
cratons. Russian geologists writing in English call the continent "Arctida" since it was given that name in 1987,
alternatively the Hyperborean craton, in reference to the
hyperborea
In Greek mythology, the Hyperboreans (, ; ) were a mythical people who lived in the far northern part of the Ecumene, known world. Their name appears to derive from the Greek , "beyond Boreas (god), Boreas" (the God of the north wind). Some schol ...
ns in
Greek mythology
Greek mythology is the body of myths originally told by the Ancient Greece, ancient Greeks, and a genre of ancient Greek folklore, today absorbed alongside Roman mythology into the broader designation of classical mythology. These stories conc ...
.
Nikolay Shatsky
Nikolay Sergeyevich Shatsky, also spelt Nicholas Shatski (; in Moscow – August 1, 1960 in Moscow) was a Soviet Union, Soviet geologist, an expert in tectonics of ancient platform (geology), platforms.[subduction
Subduction is a geological process in which the oceanic lithosphere and some continental lithosphere is recycled into the Earth's mantle at the convergent boundaries between tectonic plates. Where one tectonic plate converges with a second p ...]
. "Mobilists", on the other hand, also erroneously, proposed that North America had rifted from Eurasia and that the Arctic basins had opened behind a retreating Alaska.
Precambrian continent
In his reconstruction of the
supercontinent cycle
The supercontinent cycle is the quasi-periodic aggregation and dispersal of Earth's continental crust. There are varying opinions as to whether the amount of continental crust is increasing, decreasing, or staying about the same, but it is agree ...
, Rogers proposed that the continent
Ur formed at about 3
Ga and formed East
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 ...
in the Middle Proterozoic by accretion to
East Antarctica
East Antarctica, also called Greater Antarctica, constitutes the majority (two-thirds) of the Antarctic continent, lying primarily in the Eastern Hemisphere south of the Indian Ocean, and separated from West Antarctica by the Transantarctic ...
; Arctica formed around 2.5–2 Ga by the amalgamation of the
Canadian
Canadians () are people identified with the country of Canada. This connection may be residential, legal, historical or cultural. For most Canadians, many (or all) of these connections exist and are collectively the source of their being ''C ...
and Siberian shields plus Greenland; and
Atlantica formed around 2 Ga by the amalgamation of 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 ...
and eastern South America. Arctica then grew around 1.5 Ga by accretion of East Antarctica and
Baltica
Baltica is a paleocontinent that formed in the Paleoproterozoic and now constitutes northwestern Eurasia, or Europe north of the Trans-European Suture Zone and west of the Ural Mountains.
The thick core of Baltica, the East European Craton, i ...
to form the supercontinent
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 ...
. Around 1 Ga Nena, Ur, and Atlantica collided to form the supercontinent
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 ...
.
argued that most cratons that were around at 2.5 Ga most likely formed in a single region simply because they were located in a single region in Pangaea, which is the reason Rogers argued for the existence of Arctica.
The core of Arctica was the Canadian Shield, which named
Kenorland
Kenorland is a hypothetical Neoarchean supercontinent. If it existed, it would have been one of the earliest known supercontinents on Earth. It is thought to have formed during the Neoarchaean Era c. 2.72 billion years ago (2.72 Ga) by the acc ...
. They argued that this continent formed around 2.5 Ga and then rifted before reassembling along the 1.8 Ga
Trans-Hudson and
Taltson-Thelon orogenies. These two orogenies are derived from continental crust (not oceanic crust) and were probably intracontinental, leaving Kenorland intact from 2.5 Ga to the present. Correlations between orogenies in Canada and Siberia remain more controversial.
Laurentia
Laurentia or the North American craton is a large continental craton that forms the Geology of North America, ancient geological core of North America. Many times in its past, Laurentia has been a separate continent, as it is now in the form of ...
and Baltica were connected during the Late Palaeoproterzoic (1.7–1.74 Ga) and Siberia later joined them. Paleomagnetic reconstructions indicate that they formed a single supercontinent during the Mesoproterozoic (1.5–1.45 Ga) but paleomagnetic data and geological pieces of evidence also suggest a considerable spatial gap between Siberia and Laurentia and Arctica is thought to be the missing link.
Phanerozoic microcontinent
The current geological structure of the Arctic Region is the result of tectonic processes during the Mesozoic and Cenozoic (250
Ma to present) when the
Amerasian
An Amerasian may refer to a person born in East or Southeast Asia to an East Asian or Southeast Asian mother and a U.S. military father. Other terms used include War babies or G.I. Babies.
Several countries in East and Southeast Asia have sign ...
and
Eurasian
Eurasia ( , ) is a continental area on Earth, comprising all of Europe and Asia. According to some geographers, physiographically, Eurasia is a single supercontinent. The concept of Europe and Asia as distinct continents dates back to antiq ...
basins formed, but the presence of Precambrian metamorphic complexes discovered in the 1980s indicated a continent once existed between
Laurentia
Laurentia or the North American craton is a large continental craton that forms the Geology of North America, ancient geological core of North America. Many times in its past, Laurentia has been a separate continent, as it is now in the form of ...
,
Baltica
Baltica is a paleocontinent that formed in the Paleoproterozoic and now constitutes northwestern Eurasia, or Europe north of the Trans-European Suture Zone and west of the Ural Mountains.
The thick core of Baltica, the East European Craton, i ...
, and
Siberia
Siberia ( ; , ) is an extensive geographical region comprising all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has formed a part of the sovereign territory of Russia and its predecessor states ...
.
In the reconstruction of , Arctica originally formed as a continent during the
Tonian
The Tonian (from , meaning "stretch") is the first geologic period of the Neoproterozoic era (geology), Era. It lasted from to Mya (million years ago). Instead of being based on stratigraphy, these dates are defined by the International Commissi ...
950 Ma and became part of the supercontinent
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 ...
. It reformed during the Permian-Triassic 255 Ma and became part of
Pangaea
Pangaea or Pangea ( ) was a supercontinent that existed during the late Paleozoic and early Mesozoic eras. It assembled from the earlier continental units of Gondwana, Euramerica and Siberia during the Carboniferous period approximately 335 mi ...
. During this period the configuration of Arctica changed and the continent moved from near the Equator to near the North Pole while keeping its position between three major cratons: Laurentia, Baltica, and Siberia.
An extended magmatic event, the
High Arctic Large Igneous Province
The High Arctic Large Igneous Province (HALIP) is a Cretaceous large igneous province in the Arctic. The region is divided into several smaller magmatic provinces. Svalbard, Franz Josef Land, Sverdrup Basin, Amerasian Basin, and northern Greenla ...
, broke Arctica in part 130–90 Ma, opened the
Arctic Ocean
The Arctic Ocean is the smallest and shallowest of the world's five oceanic divisions. It spans an area of approximately and is the coldest of the world's oceans. The International Hydrographic Organization (IHO) recognizes it as an ocean, ...
, and left radiating
dyke swarm
A dike swarm (American spelling) or dyke swarm ( British spelling) is a large geological structure consisting of a major group of parallel, linear, or radially oriented magmatic dikes intruded within continental crust or central volcano ...
s across the Arctic.
Fragments of this continent include the
Kara Shelf,
New Siberian Islands
The New Siberian Islands (; ) are an archipelago in the Extreme North of Russia, to the north of the East Siberian coast between the Laptev Sea and the East Siberian Sea north of the Sakha (Yakutia) Republic, of whose Bulunsky District they ar ...
, northern
Alaska
Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...
,
Chukotka Peninsula
The Chukchi Peninsula (also Chukotka Peninsula or Chukotski Peninsula; , ''Chukotskiy poluostrov'', short form , ''Chukotka''), at about 66° N 172° W, is the easternmost peninsula of Asia. Its eastern end is at Cape Dezhnev near the village ...
, Inuit Fold Belt in northern Greenland, and two Arctic underwater ridges, the
Lomonosov and
Alpha
Alpha (uppercase , lowercase ) is the first letter of the Greek alphabet. In the system of Greek numerals, it has a value of one. Alpha is derived from the Phoenician letter ''aleph'' , whose name comes from the West Semitic word for ' ...
-
Mendeleev Ridge
The Mendeleev Ridge () or Mendeleev Rise is a broad ridge in the Arctic Ocean from the East Siberian Sea area of the Siberian Shelf to the central areas of the ocean. It is attached to the Alpha Ridge of the Amerasian Basin. It is named after Dm ...
s. More recent reconstructions also include Barentsia (including
Svalbard
Svalbard ( , ), previously known as Spitsbergen or Spitzbergen, is a Norway, Norwegian archipelago that lies at the convergence of the Arctic Ocean with the Atlantic Ocean. North of continental Europe, mainland Europe, it lies about midway be ...
and Timan-Pechora Plates).
Remains of the last continent are now located on the
Kara Sea
The Kara Sea is a marginal sea, separated from the Barents Sea to the west by the Kara Strait and Novaya Zemlya, and from the Laptev Sea to the east by the Severnaya Zemlya archipelago. Ultimately the Kara, Barents and Laptev Seas are all ...
Shelf,
New Siberian Islands
The New Siberian Islands (; ) are an archipelago in the Extreme North of Russia, to the north of the East Siberian coast between the Laptev Sea and the East Siberian Sea north of the Sakha (Yakutia) Republic, of whose Bulunsky District they ar ...
and adjacent shelf,
Alaska
Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...
north of
Brooks Ridge,
Chukchi Peninsula
The Chukchi Peninsula (also Chukotka Peninsula or Chukotski Peninsula; , ''Chukotskiy poluostrov'', short form , ''Chukotka''), at about 66° N 172° W, is the easternmost peninsula of Asia. Its eastern end is at Cape Dezhnev near the village ...
in easternmost Siberia, and fragments in northern
Greenland
Greenland is an autonomous territory in the Danish Realm, Kingdom of Denmark. It is by far the largest geographically of three constituent parts of the kingdom; the other two are metropolitan Denmark and the Faroe Islands. Citizens of Greenlan ...
and
Northern Canada
Northern Canada (), colloquially the North or the Territories, is the vast northernmost region of Canada, variously defined by geography and politics. Politically, the term refers to the three Provinces_and_territories_of_Canada#Territories, terr ...
and in the submerged
Lomonosov Ridge
The Lomonosov Ridge (, ) is an unusual underwater ridge of continental crust in the Arctic Ocean. It spans between the New Siberian Islands over the central part of the ocean to Ellesmere Island of the Canadian Arctic Archipelago.CBC NewsBroken ...
.
See also
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References
Notes
Sources
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{{Continents of the world
Historical continents
Archean
Proterozoic
Natural history of Asia
Natural history of North America
Prehistory of the Arctic
Former supercontinents