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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.
Orogeny typically produces orogenic belts, which are elongated regions of deformation bordering continental cratons. Young orogenic belts, in which subduction is still taking place, are characterized by frequent volcanic activity and earthquakes. Older orogenic belts are typically deeply eroded to expose displaced and deformed strata.
The long-term tectonic stability of those cratons is why we find continental crust ranging up to a few billion years in age. [16] It is believed that 43% of modern continental crust was formed in the Proterozoic, 39% formed in the Archean, and only 18% in the Phanerozoic. [14]
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 ...
[1] [3] [4] The North China Craton is an ancient craton, which experienced a long period of stability and fitted the definition of a craton well. [1] However, the North China Craton later experienced destruction of some of its deeper parts (decratonization), which means that this piece of continent is no longer as stable.
Former cratons (1 P) S. Shields (geology) (14 P) Pages in category "Cratons" The following 40 pages are in this category, out of 40 total.
The discipline of anatomy can be subdivided into a number of branches, including gross or macroscopic anatomy and microscopic anatomy. [9] Gross anatomy is the study of structures large enough to be seen with the naked eye, and also includes superficial anatomy or surface anatomy, the study by sight of the external body features.