The Crashsite Group of the Ellsworth Mountains, a 3,000-m-thick sequence of shallow-water, mostly marine, tan, green, and red quartzose sandstones (quartzites) and argillites, is here subdivided, in ascending order, into the Howard Nunataks Formation (1,630 m), the Mount Liptak Formation 1,070 m), and the Mount Wyatt Earp Formation (300 m). The Mount Wyatt Earp Formation has yielded Devonian fossils. Late Cambrian trilobites occur in the transition beds at the base of the Crashsite Group, and it is probable that the lower parts of the Group include Ordovician and Silurian strata.