Redirected from Death Valley
Death Valley National Monument was created in 1933. In 1994, the Monument was promoted to the status of National Park, as well as being substantially expanded. In addition to the main body of the park, there is a small portion, called Devil's Hole[?] located farther east in Nevada, near the Ash Meadows National Wildlife Preserve[?].
Within the park there are two major valleys; Death Valley and Panamint Valley - both of which where formed within the last few million years. Death Valley is five mountain ranges removed from the Pacific Ocean so due the rainshadow effect[?] the originally water-laden air mass arrive in Death Valley in a fairy dry state.
The floor of Death Valley is rich in minerals, such as borax. For many years, a mining and smelting company operated here, producing borax for use in soap. The end product was shipped out of the valley in wagons pulled by teams of 18 mules and 2 horses each, hence the brand name 20-Mule Team.
Bighorn sheep[?] live in and around the park. They are a rare species of mountain sheep[?] that exist in isolated bands in the Sierra and in Death Valley. These are highly adaptable animals and can eat almost any plant. They have no known predators, but humans and borros[?] compete for habitat.
Geology The park has a diverse geologic history. Since its formation, the area that comprises the park has experienced at least four major periods of extensive volcanism, three or four periods of major sedimentation[?], several intervals of major tectonic deformation and there has also been at least two periods of glaciation.
Death and Panamint valleys both follow the general trend of basin and range topography with one modification: there are parallel strike-slip faults[?] that perpendicularly bound the central extent of Death Valley. The result of this shearing action is additional extension in the central part of Death Valley which causes a slight widening and additional subsidence there.
Also in many places the mountain ranges are actively uplifting. In Death Valley both the Panamints and especially the Black Mountains are uplifting. The uplift on the Black Mountains is so fast that the alluvial fans there are relatively small and steep compared to the huge alluvial fans coming from valley washes off of the Paramount Mountains. In many places so-called "wine glass canyons" are formed as a result. This type of canyon results from the relatively fast uplift on this mountain range which doesn't allow the canyons cut into the range time enough to form a classic v-shape all the way down to the stream bed. Instead a v-shape grading down to a slot canyon is the result along with a relatively small and steep alluvial fan for the stream sediments to collect on. These particular features form what looks like a [[wine glass]] from a distance.
Further complicating this picture is the fact that Death Valley is also twisting which forms lateral strike-slip faults[?] and this is a major reason why Badwater Basin is so low.
Geologists call all the manifestations of this body of water Lake Manly[?] and at its height during the Great Ice Age[?] 15,000 years ago water from three rivers and many streams fed this lake forming a water body 500-600 feet deep, about 8-10 miles wide and 100 miles long. But the saltpans[?] seen on the valley floor are from the 30 feet deep Recent Lake which dried-up only a few thousand years ago.
Shoreline Butte has easy to see weak shorelines on it called strandlines that were formed by wave action from Lake Many. These features were created by different stands of the lake - an ancient lake that never had an outlet and therefore its depth would often change with time and slight changes in climate. The conditions under which this lake existed are called 'pluvial[?]' by geologists instead of glacial because glaciers did not directly touch Death Valley - but the meltwater from the glaciers and the cooler and wetter temperatures of the time did effect the valley.
Places of Interest in Death Valley National Park
Pinion Pine and Juniper trees dominate the landscape here with bushes of Mormon Tea[?] in between.
The mountain that Dante's View is on is part of the Black Mountains[?] which along with the parallel Panamint Mountains[?] across the valley form what geologists call a horst[?] and the valley that is called a graben[?].
These structures are created when the surface of the earth is under extensional, or a pulling force. The crust responds to this force by sending a large and long roughly v-shaped block of crust down which forms the bedrock of the valley floor (see basin and range).
In between many of the dunes are stands of creosotebush[?] and some mesquite[?] on the sand and on dried mud, which used to cover this part of the valley before the dunes intruded (mesquite was the dominant plant here before the sand dunes but creosote does much better in the sand dune conditions).
The petroglyphs here are made possible because many of the rocks in these arid conditions have desert varnish on them. This particular form of desert varnish takes 10,000 years to make 1/100th of an inch of varnish and is deposited by a certain type of bacteria that collects the iron, manganese and clay needed to make the varnish.
Also, since varnish is created at a predictable rate, it is possible to date petroglyphs based on the amount of re-varnishing that has taken place since the marks were made. Varnish does not normally form on carbonate rocks because their surfaces weather too easily.
In a wash near some of the petroglyphs there is a fault scarp[?] that exposes some fanglomerate which is a type of sedimentary rock which looks like concrete with large rocks intermixed. In fact it is lithified alluvial sediment.
The dominant rock-type here is dolomite which is a type of carbonate rock that formed in a warm shallow sea that covered the area of Death Valley 750 million years ago. This particular formation is called the Noonday Dolomite[?] and has been tilted from uplift.
Native Americans who wrote petroglyphs on some of the rock faces - especially at springs or other points of interest.
Leadfield is a ghost town near Titus Canyon where in the 1920s prospectors mined for ore after hearing exaggerated claims that ore would be easy to find and the living conditions in the area would be easy to endure.
At one of the bends in the canyon mega breccia can be seen and several different types of flowers including the sacred detura[?] inhabit the area.
As can be seen in the picture there is a series of gray layers near the rim of the crater and lighter-colored sediments further down. The gray layers are from the phreatic eruptions that have recently occurred in this area but the lighter-colored rock is derived from ocean sediment. There is also a difference in color between these seabed sediments: On the left these sediments are yellowish in hue while on the right they are orange. The reason is due to a fault that separates the two different sedimentary units; over time movement along this fault has resulted in the abutment of these two different sedimentary units.
Winds at the rim of the crater are very strong and often gust above 50 MPH.
Winds on this ridge are concentrated and compressed at the top of the hill and are very fast as a result. These strong winds pick-up dust and sand, which literally sand-blasts their surfaces.
Search Encyclopedia
|
Featured Article
|