The Polar Plateau in this area is a rock surface thinly veneered with ice and lies at a height 8,000 to 11,000 ft above sea level. Three major groups of rocks are present: (1) Volcanics of late Tertiary and Quaternary age including kenyte and related rock types; (2) Volcanics (mostly basalt) of Triassic-Jurassic age with minor sediments; and (3) A basement complex consisting mostly of granite and gneissic granite digesting regional biotite schist of probable Precambrian age.