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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 .
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.
The São Luís and the Luis Alves cratonic fragments (Brazil) are shown, but the Arequipa–Antofalla Craton and some minor African cratons are not. Other versions describe the Guiana Shield separated from the Amazonian Shield by a depression, and the Saharan Metacraton as a part of this West African Craton .
Figure 1. Map of East and West Antarctica separated by the Transantarctic Mountain Range. The East Antarctic Shield or Craton is a cratonic rock body that covers 10.2 million square kilometers or roughly 73% of the continent of Antarctica. [1]
Some terranes, such as the Kapuskasing Uplift, were formed from the uplifting of the crustal block. For example, during 1.85 Ga, the American Midcontinent and the Superior Craton collided. The collision between the two cratons triggered an Archean reverse fault, the Ivanhoe Lake fault. The upward movement of the hanging wall causes the uplift ...
Trans-Hudson orogen and the Wyoming, Superior and Hearne cratons The Trans-Hudson orogeny or Trans-Hudsonian orogeny was the major mountain building event ( orogeny ) that formed the Precambrian Canadian Shield and the North American Craton (also called Laurentia ), forging the initial North American continent .