Death Valley National Monument

Death Valley is a 250-kilometer (156-mile) long, down-dropped, east-tilting structural trough. Included in the Monument are approximately 190 kilometers (120 miles) of the Valley as well as the bordering block-faulted mountains, the Grapevine, Black and Funeral on the east, and the Cottonwood and Panamints on the west.

Geological formations present range from Precambrian metamorphics, through Paleozoic marine sedimentaries and metasedimentaries, Tertiary nonmarine sedimentaries, Miocene and Cenozoic volcanics, to Pleistocene and Recent saline, alluvial and lacustrine deposits.

Several faults, mainly the Furnace Creek and Death Valley, traverse the area, and many associated features such as turtlebacks, graben, scarps, etc., are readily visible. Excellent examples of alluvial fans, desert playas, maars, and sand dunes are among the many geological features found in the Monument.

Pleistocene Lake Manly once filled the trough to a depth of 180 meters (600 feet), and remnant lake terraces and shorelines are present. Between 2,000 and 5,000 years B.P. there was a shallow pond 10 meters (30 feet) deep in portions of the Valley. Fossils are present, the most noteworthy being in the early Oligocene Titus Canyon Formation which has yielded specimens of Mesohippus, Leptomeryx ("deerlets"), brontotheres, camelids, tapirs, rhinoceros, oreodonts and various primitive rodents.

Seven plant communities occur in the Monument. They are (with dominants) an alkali sink community (Prosopis spp. and Atriplex spp.), creosote bush scrub (Larrea tridentata), shadscale scrub (Atriplex confertifolia), sagebrush scrub (Coleogyne ramosissima, Artemisia tridentata), pinyon-juniper woodland (Pinus monophylla), subalpine forest (Pinus flexilis), and a bristlecone pine forest (Pinus longaeva).

Twenty-one species or subspecies of plants are endemic to the Monument, and twelve are endemic to the monument and the adjacent areas. Eleven of the former are considered rare: Gilmania luteola, Eriogonum gilmanii, Eriogonum intrafractum, Sibara deserti, Sphaeralcea rusbyi var. eremicola, Petalonyx thurberi ssp. gilmanii, Camissonia kernensis ssp. gilmanii, Mimulus rupicola, Maurandya petrophila, Galium hypotrichium ssp. tomentellum and Enceliopsis covillei, as are four of the latter: Arctomecon merriamii, Mentzelia reflexa, Brickellia knappiana, and Ericameria gilmanii.

A wide variety of animal life has been observed here, including 53 species of mammals, 307 of birds, 36 of reptiles, 3 amphibian and 6 fish. Of note are the bighorn sheep, Ovis canadensis nelsoni, the Panamint alligator lizard, Gerrhonotus panamintinus, and the rare Cottonball Marsh pupfish, Cyprinodon milleri, known only from the marsh.

Integrity: There are roads, recreational and maintenance facilities and some mining. Over 90 percent of the Monument has been proposed for Wilderness classification. Feral burros are competing with the sheep and have devastated portions of the Monument.

Use: Research, educational, observational, present.

Ref: Draft Environmental Statement, Proposed Wilderness Area, Death Valley National Monument. 1974, National Park Service, Denver, Colorado.

March 1980