Craton

Old and stable part of the continental lithosphere

In geology, a craton ( KRAYT-on, KRAT-on, or KRAY-tən; from Ancient Greek κράτος (kratos) 'strength') is an old and stable part of continental lithosphere (the Earth's two topmost layers, the crust and the lithospheric mantle). Having often survived cycles of merging and rifting of continents, cratons are generally found in the interiors of tectonic plates; the exceptions occur where geologically recent rifting events have separated cratons and created passive margins along their edges. Cratons are composed of ancient crystalline basement rocks covered by younger sedimentary rocks.

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