In Greenland and Arctic Scandinavia, Devonian sedimentary rocks crop out in only two areas: (1) east Greenland between lat. 71½°N and 74½°N; and (2) Svalbard, between lat. 76½°N and 80°N in Vestspitsbergen. These strata are nonmarine clastics. Aggregate thicknesses are large, up to 7,000 m in Greenland and 5,000-6,500 m in Vestspitsbergen. In both areas, the successions are unconformable on deformed pre-Devonian, Caledonian rocks. Both areas are well known for their fossil vertebrates, on which the following age determinations depend.

In Greenland the successions can be assigned to 5 major units, each with a maximum thickness of 1,000-3,000 m: (1) A unit that includes the Vilddal Group, of red and gray siltstone, conglomerate, sandstone, volcanic rock, and granite intrusions; (2) a unit of conglomerates, and red and gray-green sandstone; (3) the Kap Kolthoff Formation of gray-green sandstone; (4) Kap Graah Group of red sandstone, siltstone, and volcanic rock; and (5) the Mt. Celsius Supergroup of red and gray-green siltstone with some sandstone. Units (1) and (2) are dated as Givetian (late Middle Devonian), and units (4) and (5) are dated as Famennian (late Upper Devonian). Unconformities between and within these units occur, particularly in the northeast part of the area, and the rocks were folded again before de osition of the nonmarine Carboniferous.

In Svalbard, the succession consists of 4 major units, each with a maximum thickness of 1,000-3,000 m: (1) the Siktefjellet Group of conglomerate and sandstone beds; (2) the Red Bay Group of conglomerates and sandstone beds; (3) the Wood Bay Formation of sandstone and red siltstone; and (4) a supergroup (Grey Hoek and Wijde Bay Formations, Mimer Valley Group) of gray conglomerate, sandstone, and siltstone. There is no fossil evidence for the date of (1) which was strongly folded before the deposition of (2). Unit (2) is dated as Gedinnian (early Lower Devonian), and the succession is continuous through (3) to (4), which ranges up to Givetian (late Middle Devonian) in age. These units were folded strongly before the deposition of Carboniferous sediments.

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