They consist of a series of unfossiliferous crystalline slates.
In the north the plateau is overlain by red and purple unfossiliferous sandstones, capped near its edge by a cherty limestone also unfossiliferous but possibly of Lower Cretaceous age.
Greenland, but as they are unfossiliferous sandstone, rapidly disintegrating, this cannot be known.
The former appears to be almost unfossiliferous, the latter has yielded a rich marine fauna, which belongs to the top of the Carboniferous or to the Permo-carboniferous.
So far it has proved to be unfossiliferous.