The 5,500+-m Paleozoic succession of the Sentinel Range includes the Heritage Group (Cambrian), the Crashsite Group (Cambrian and younger, including Devonian), the Whiteout Conglomerate (Carboniferous?), and the Polarstar Formation (Permian). All these predominantly clastic rocks were strongly folded during the early Mesozoic (?) Ellsworth (Gondwanide) Orogeny, and the folds formed mainly by a flexural-slip mechanism. Axial planar cleavage is abundant throughout the range; it may be a solution cleavage in the massive diamictite beds of the Whiteout Conglomerate. One major, eastward-dipping reverse (?) fault cuts Crashsite quartzite beds along the west side of range. The Sentinel Range succession was subjected...