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the upper stage of the Triassic. The Rhaetian Stage was identified by the German geologist C. W. Gumbel in 1858. The typical cross section (the Rhaetian Alps) is composed of alternating layers of marls and limestones below (the Koessen Facies) and limestones and dolomites above (the Dachstein Facies).
Until 1963, French geologists put the Rhaetian Stage at the base of the Jurassic. The German geologists F. Fabricius, M. Urlichs, and J. Wiedmann and the Austrian geologists C. Zapfe and L. Krystyn questioned the independence of the Rhaetian Stage, considering it a facies of the Norian Stage. Rhaetian Stage deposits are found in Eurasia, Greenland, North America, and New Zealand and on the island of Timor.