Click here to see a geologic image tour of Arches National Park. Website images include both standard photograph and 3D views (as anaglyphs - requiring red-and-cyan 3D viewing glasses). This image shows Delicate Arch in the Entrada Sandstone. Morrison Formation crops out in the Salt Valley Wash in the distance.

Generalized stratigraphy after Doelling, Helmut H., 2000, Geology of Arches National Park, Grand County, Utah: In Geology of Utah's Parks and Monuments, Sprinkel, D.A., Chidsey, T. C., and Anderson, P. B., editors, Utah Geological Association Publication 28., p. 11-36.

See also:

Hintze, L. F., 1988, Geologic History of Utah; A Field Guide to Utah's Rocks: Brigham Young University Geology Studies Special Publication 7, p. 183 [Chart 84 - Moab-Arches-La Sal area].

Stratigraphic unit information is modified from the USGS GeoLex (Lexicon of Geology): http://ngmdb.usgs.gov/Geolex/geolex_qs.html.

Information about the Geologic Time Scale is available here.