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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 ...
The broad central parts of continents are called cratons, and are subject to epeirogeny. [2] The movement may be one of subsidence toward, or of uplift from, the center of Earth. The movement is caused by a set of forces acting along an Earth radius, such as those contributing to isostasy and faulting in the lithosphere.
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.
Idealized cross-section of Earth's lithosphere, including the relationship between cratons, shields and platforms (Abbreviations: cb=cratonic basin, LIP=large igneous province, MOR=mid-ocean ridge) The term shield cannot be used interchangeably with the term craton. However, shield can be used interchangeably with the term basement.
The metamorphic record of the craton is characteristic of Paleoproterozoic plate tectonics. A definitive evolution of the area has not been determined as a result of conflicting interpretation of the relationship between low-grade greenstone belts and high-grade gneissic terranes dominated by TTG suites. [8]
Cratons consist primarily of two alternating types of terranes. The first are so-called greenstone belts, consisting of low-grade metamorphosed sedimentary rocks. These "greenstones" are similar to the sediments today found in oceanic trenches, above subduction zones. For this reason, greenstones are sometimes seen as evidence for subduction ...
Pluto likely acquired large moon Charon in a “kiss and capture” collision billions of years ago. It may have created a subsurface ocean on the icy dwarf planet.
Idealized cross-section of Earth's lithosphere, including the relationship between cratons, shields and platforms (Abbreviations: cb=cratonic basin, LIP=large igneous province, MOR=mid-ocean ridge) In geology, a platform is a continental area covered by relatively flat or gently tilted, mainly sedimentary strata , which overlie a basement of ...