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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 ...
Cratons whose ancient rocks are widely exposed at the surface, often with relatively subdued relief, are known as shields. If the ancient rocks are largely overlain by a cover of younger rocks then the 'hidden' craton may be referred to as a platform .
West Africa. The craton appears to have formed when three Archean cratons fused: Leo-Man-Ghana, Taoudeni and Reguibat. The first two docked around 2.1 Ga (billion years ago), and the Reguibat Craton docked with the craton around 2 Ga.
Smaller cratons of Precambrian rocks south of the Amazonian Shield are the Río de la Plata Craton and the São Francisco Craton, which lies to the east. The Río Apa Craton at the Paraguay-Brazil border is considered to be likely just the southern part of the Amazonian Craton. [2] The rocks of Río Apa were deformed during the Sunsás orogeny. [3]
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.
Approximate location of Mesoproterozoic (older than 1.3 Ga) cratons within South America–Africa in their Gondwana configuration (c. 550-130 Ma).. The Congo Craton, covered by the Palaeozoic-to-recent Congo Basin, is an ancient Precambrian craton that with four others (the Kaapvaal, Zimbabwe, Tanzania, and West African cratons) makes up the modern continent of Africa.
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.
He derived the map based on the age of the greenstone belts found in the Craton. He suggested that the greenstone belt was formed by collision of some micro blocks. [19] [20] [21] The green belt on the map shows a younger greenstone belt, formed 2.5 billion years ago, while the yellow one showed the greenstone belt formed 2.6–2.7 billion ...