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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 degree of certainty to which the identified landmasses can be regarded as independent entities reduces as geologists look further back in time. The list includes cratons, supercratons, microcontinents, continents and supercontinents. For the Archean to Paleoproterozoic cores of most of the continents see also list of shields and cratons.
Approximate location of Mesoproterozoic (older than 1.3 Ga) cratons in South America and Africa (the Saharan Metacraton is not shown). The Earth formed about 4.54 billion years ago. [11] As it cooled, the lithosphere, consisting of the crust and the rigid uppermost part of the mantle, solidified.
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]
A craton is a large part of the Earth's crust that has been stable and subjected to very little geological changes over a long time. [2] The size of Superior Craton is about 1,572,000 km 2. [3] The craton underwent a series of events from 4.3 to 2.57 Ga. These events included the growth, drifting and deformation of both oceanic and continental ...
The Pilbara Craton is one of only two pristine Archaean 3.8–2.7 Ga (billion years ago) crusts identified on the Earth, along with the Kaapvaal Craton in South Africa. The youngest rocks are 1.7 Ga old in the historic area assigned to the Craton. [1] Both locations may have once been part of the Vaalbara supercontinent or the continent of Ur.
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.