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Cratons of South America and Africa during the Triassic Period when the two continents were joined as part of the Pangea supercontinent. A craton (/ ˈ k r eɪ t ɒ n / KRAYT-on, / ˈ k r æ t ɒ n / KRAT-on, or / ˈ k r eɪ t ən / KRAY-tən; [1] [2] [3] from Ancient Greek: κράτος kratos "strength") is an old and stable part of the continental lithosphere, which consists of Earth's two ...
A craton is an ancient part of the Earth's continental crust which has been more or less stable since Precambrian times. Cratons whose ancient rocks are widely exposed at the surface, often with relatively subdued relief, are known as shields.
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. [1]
Laurentia basement rocks. Laurentia or the North American Craton is a large continental craton that forms the 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 North America, although originally it also included the cratonic areas of Greenland and the Hebridean Terrane in northwest Scotland.
In geology, a supercontinent is the assembly of most or all of Earth's continental blocks or cratons to form a single large landmass. [1] [2] [3] However, some geologists use a different definition, "a grouping of formerly dispersed continents", which leaves room for interpretation and is easier to apply to Precambrian times. [4]
Cratons have largely been unaffected by mountain-building events since the Precambrian. A craton typically consists of a continental shield surrounded by a continental platform . The shield is a region where ancient crystalline basement rock (typically 1.5 to 3.8 billion years old) is widely exposed at the surface.
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Approximate location of Mesoproterozoic (older than 1.3 Ga) cratons in South America and Africa.. The Kalahari Craton is a craton, an old and stable part of the continental lithosphere, that occupies large portions of South Africa, Botswana, Namibia and Zimbabwe.