Cratons/Shields | Hypothetical Continents: G (=109 years) | |||||||||||||||
| 3.6 | 2.8 | 2.7 | 2.1 | 2.0 | 1.8 | 1.1 | 0.6 | 0.3 | ||||||||
| Va alb ara | Ur | Ken orl and | Arc tica | At lan tic a | Co lum bia | Ro din ia | Pan no tia | Pan ga ea | ||||||||
| Africa | 01 | Kaap vaal | Kalahari | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | |||||
| 02 | Zim bab we | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||
| 03 | Con go | Central Africa | ✔ | ✔ | ✔ | ✔ | ✔ | |||||||||
| 04 | Tan- zania | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||||
| 05 | West Africa | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||||
| Western Australia | 06 | Pilbara | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | |||||||
| 07 | Yilgarn | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | |||||||||
| 08 | Gawler | ✔ | ✔ | ✔ | ✔ | |||||||||||
| 09 | Kimberley | ✔ | ✔ | ✔ | ✔ | |||||||||||
| – | 10 | Madagascar | ✔ | ✔ | ✔ | ✔ | ✔ | |||||||||
| India | 11 | Bhandara | ✔ | ✔ | ✔ | ✔ | ✔ | |||||||||
| 12 | Dharwar | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||||
| 13 | Singhbhum | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||||
| East Antarctica | 14 | Dronning | ✔ | ✔ | ✔ | ✔ | ✔ | |||||||||
| 15 | Napier | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||||
| 16 | Vestfold | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||||
| Laurentia (North America) | 17 | Hearne | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||
| 18 | Rae | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | |||||||||
| 19 | Slave | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | |||||||||
| 20 | Superior | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | |||||||||
| 21 | Wyoming | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | |||||||||
| 22 | Nain | North Atlantic | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||
| 23 | Greenland | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | |||||||||
| 24 | NW Scotland | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | |||||||||
| Europe | 25 | Fennoscandia | Baltica | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||
| 26 | Sarmatia | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||||
| 27 | Volgo-Uralia | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||||
| Asia | 28 | Aldan | Siberia | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||
| 29 | Anabar | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||||
| South America | 30 | Guaporé | Amazonia | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||
| 31 | Guiana | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||||
| 32 | Rio de la Plata | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||||
| 33 | São Francisco | ✔ | ✔ | ✔ | ✔ | ✔ | ||||||||||
| China | 34 | North China | ✔ | ✔ | ✔ | ✔ | ||||||||||
| 35 | South China | ✔ | ✔ | ✔ | ✔ | |||||||||||
| 36 | Tarim | ✔ | ✔ | ✔ | ✔ | |||||||||||
| – | 37 | Arabia | ✔ | ✔ | ||||||||||||
| – | 38 | Kazakhstania | ✔ | |||||||||||||
Vaalbara (3636-2803 mya), Earth’s first hypothetically composed continent, comprised the earliest known two cratons: Kaapvaal (South Africa) and Pilbara (Western Australia).
Ur (2803-2408 mya) comprised Africa (Kalahari=Kaapvaal plus Zimbabwe), Madagascar, India (Bhandara, Dharwar and Singhbhum), East Antarctica (Dronning Maud Land, Napier and Vestfold) and Western Australia (Pilbara and Yilgarn).
Kenorland (2720-2114 mya) comprised Laurentia/North America (Hearne, Rae, Slave, Superior, Wyoming, North Atlantic=Nain, Greenland and northwest Scotland), Baltica/ eastern Europe (Fennoscandia, Sarmatia and Volgo-Uralia), Africa and Western Australia.
Arctica (2114-1995 mya) comprised Laurentia and Siberia/ Asia (Aldan and Anabar). Atlantica (1991-1124 mya) comprised Africa (Kalahari, West Africa and Central Africa= Congo+Tanzania) and South America (Rio de la Plata, São Francisco and Amazonia=Guaporé plus Guiana).
The four most recent major assemblies each had most of today’s landmasses and are called supercontinents. Columbia/ Nuna (1820-1350 mya) comprised Arctica, Atlantica, Baltica, Madagascar, India, East Antarctica, Western Australia (Pilbara, Yilgarn, Gawler and Kimberley) and China (North China, South China and Tarim).
Rodinia (1130-750 mya) had Laurentia, Baltica, Siberia and North China positioned between two major groups: Proto-West Gondwana (South America, Africa and Arabia) and Proto-East Gondwana (Madagascar, India, East Antarctica, Western Australia, South China and Tarim).
Around 800 mya these two groups broke away and began moving closer together until the eastern edge of ‘West Gondwana’ (Africa) hit the western edge of ‘East Gondwana’ (Madagascar, India) to form the continent Gondwana, which together with Laurentia, Baltica and Siberia became the supercontinent Pannotia (633-573 mya).
By 550 mya Pannotia had separated into the four principal Palaeozoic continents: Laurentia forming the Iapetus Ocean with Gondwana, Baltica forming the Tornquist Ocean with Gondwana, and Siberia forming the Ural Ocean with Baltica.
The Avalonia terrane rifted from northwest Gondwana about 480 mya then drifted northwards opening the Rheic Ocean behind and narrowing the Tornquist and Iapetus oceans in front. Around 440 mya it collided with Baltica, closing the Tornquist Ocean.
During the Caledonian Orogeny (490-390 mya), Baltica-Avalonia collided 415 mya with Laurentia, closing the Iapetus, forming the continent Laurussia/Euramerica (415-336 mya) and creating the mountain belt that runs west to east through Northern Ireland, northern Britain, Scandinavia, Svalbard, eastern Greenland and parts of north-central Europe.
West Avalonia coincides with Newfoundland, Prince Edward Island, Nova Scotia, southern New Brunswick and east coast New England; East Avalonia coincides with southern Ireland, Wales, England and north coast northern Europe.
Armorica (the Brittany terrane) and Hun superterrane rifted from northern Gondwana 430 mya and drifted northwards towards Laurussia, opening the Prototethys Ocean behind and beginning the closure of the Rheic Ocean in front. Around 380 mya the Armorican and the Hun terranes collided with east Laurussia thus closing the eastern Rheic.
During the Variscan Orogeny (380-290 mya), northwest Gondwana (South America-Africa) collided obliquely with southwest Euramerica (North America), closing the western Rheic and forming the C-shaped supercontinent Pangaea (336-175 mya). Centred on the equator, Pangaea extended from North Pole to South Pole, surrounded by the global ocean Panthalassa (the precursor to the Pacific Ocean). The Palaeotethys confined on three sides by the crescent opened out eastwards to the Panthalassa. The orogeny created the mountain belt that runs west to east though southwest Ireland, southwest Britain, Portugal, Spain, France and central Europe.
During the Uralian Orogeny (320-250 mya), Kazakhstania (Central Asia) collided with Siberia. They continued moving towards Laurussia/Euramerica and eventually collided with Baltica about 300 mya ago to form Eurasia (Baltica, Siberia and Kazakhstania) and Laurentia (Eurasia and Laurentia), closed the Ural Ocean and created the Ural mountains
Cimmeria (parts of Turkey, Iran, Afghanistan, Pakistan, Tibet, China, Myanmar, Thailand and Malaysia), a long string of terranes, rifted from Gondwana 250 mya and drifted northwards towards Laurasia, narrowing the Palaeotethys in front and opening the Mesotethys behind. Rotating anticlockwise about a focus point near Spain it eventually collided with Laurasia around 150 mya.
| RODINIA (1139-759 mya) | ||
| Madagascar | ||
| India | ||
| Laurentia | South America | East Antarctica |
| Baltica | Africa-Arabia | Australia/China |
| Siberia | West Gondwana | East Gondwana |
| PANNOTIA (633-573 mya) | ||
| Laurentia | GONDWANA | |
| Baltica | South America | Madagascar |
| Siberia | Africa-Arabia | India |
| Avalonia | ← Avalonia | East Antarctica |
| LAURUSSIA | ← Armorica/Hun | Australia/China |
| PANGAEA (336-175 mya) | ||
| Baltica | South America | Madagascar |
| Siberia | Africa-Arabia | India |
| Kazakhstania | East Antarctica | |
| EURASIA | Australia/China | |
| Eurasia | West Gondwana | East Gondwana |
| Laurentia | ||
| LAURASIA | ← Cimmeria | |
The China blocks were never part of Pangaea but they may have fused with Eurasia around the Late Jurassic (160-145 mya) and Early Cretaceous (145-120 mya) periods.
Pangaea began to breakup up 195 mya with the separation of Laurasia and Gondwana by the Central Atlantic Ocean appearing between North America and South America-northwestern Africa. Laurasia was forced clockwise against Gondwana rotating anticlockwise causing Eurasia to move southwards towards northeastern Africa-East Gondwana, thus narrowing the Mezo/Neotethys Ocean.
Madagascar-India split from East Antarctica-West Australia 140 mya and South America separated from Africa, opening up the South Atlantic. India began drifting northwards towards Eurasia 120 mya
During the Alpine Orogeny (65-2.5 mya) Africa and India crashed into Eurasia and produced the mountain belt that runs through southern Europe, West Asia, East Asia and Southeast Asia. The remnants of western Neotethys (Alpine Tethys) include the Aral, Caspian and Black seas, formerly an inland extension of the Alpine Tethys known as the Paratethys, and the Mediterranean Sea. Around 54 mya, seafloor spreading from the North Atlantic rifted Greenland from Eurasia.
Prior to its flooding, the Mediterranean was an inland lake of which the salt layers were abruptly succeeded by marine deposits dated at 5.33 mya, suggesting a breach of the narrow land bridge connecting Gibraltar and Morocco.
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