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East European Craton, the core of Baltica. Volgo-Uralian Craton, Russia (3.0–2.7 Ga) Baltic Shield, part of the East European Craton; Fennoscandian Shield, the exposed Northwestern part of the Baltic Shield in Norway, Sweden and Finland (3.1 Ga) Karelian Craton, part of the Fennoscandian Shield in Southeast Finland and Karelia Russia, (3.4 Ga)
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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 topmost layers, the crust and the uppermost mantle.
Cambrian blue clay outcrop at beach of Gulf of Finland in Voka Estonia is part of the East European Craton , with an average continental crust thickness between 40 and 64 kilometers. The crust consolidated during the Svecofennian Orogeny in the late Paleoproterozoic , nearly two billion years ago.
During the Wopmay orogeny, subduction occurred as oceanic crust of the Slave Craton was subducted beneath an eastward-moving continental plate. Likewise, during the Trans-Hudson orogeny, rifting at first separated the Superior craton from the rest of the continent. Then the Superior Craton reversed its direction and the ocean basin began to close.
The North American Craton, also called Laurentia. The Wyoming Craton is a craton in the west-central United States and western Canada – more specifically, in Montana, Wyoming, southern Alberta, southern Saskatchewan, and parts of northern Utah. Also called the Wyoming Province, it is the initial core of the continental crust of North America.
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 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] The shield is almost entirely buried by the East Antarctic Ice Sheet that has an average thickness of 2200 meters but reaches up to 4700 meters in some locations.