Arches National Park

This view is along a trail amongst the rock fins in the Fiery Furnace area. Rock fins form from weathering and erosion along vertical joints in the sandstone. The fractures probably formed in the Entrada Sandstone during the formation of the Salt Valley anticline. The Salt Valley anticline runs roughly northwest-southeast through the park beneath Salt Valley (see map on main page) (Cruikshank, 1995). The region where most of the arches and fins occur are on the flanks of the anticline where the Entrada Sandstone is exposed at the surface.