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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.
Europe consists of the following cratons and terranes and microcontinents: the Baltica craton - Scandinavia, Finland, the Baltic states, Russia, northern Poland and northern Germany, Avalonian fragments - England, Ireland, Netherlands, northern Germany, etc., Laurentian (North American) fragments - Western Norway and Scotland,
Scientists discovered "deep mantle waves" causing interiors of continents to rise. Now we understand mantle processes and impacts on biodiversity and climate. The Continents Are Secretly Rising ...
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. The roots of the combined craton extend to a depth of over 300 km (190 mi) in the sub-continental lithospheric mantle. [4]
The oldest parts of continental lithosphere underlie cratons, and the mantle lithosphere there is thicker and less dense than typical; the relatively low density of such mantle "roots of cratons" helps to stabilize these regions. [12] [13]
The overall stability of a craton is highly correlated to the presence of a strong and deep continental lithospheric mantle because it protects the crust from thermal erosion and mitigates the effects of tectonism. [7] The Slave Craton shows a long history of continental lithospheric mantle formation.