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Death Valley National Park

Coordinates:36°14′31″N116°49′33″W / 36.24194°N 116.82583°W /36.24194; -116.82583
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From Wikipedia, the free encyclopedia
National park in California and Nevada, United States

Death Valley National Park
Sand dunes in Death Valley National Park
Map
LocationCalifornia andNevada, United States
Nearest cityLone Pine, California
Beatty, Nevada
Coordinates36°14′31″N116°49′33″W / 36.24194°N 116.82583°W /36.24194; -116.82583
Area3,422,024 acres (13,848.44 km2)[2]
EstablishedFebruary 11, 1933 (1933-02-11) as a national monument
October 31, 1994 (1994-10-31) as a national park[3]
Visitors1,128,862 (in 2022)[4]
Governing bodyNational Park Service
Websitenps.gov/deva

Death Valley National Park is anational park of the United States that straddles theCaliforniaNevada border, east of theSierra Nevada. The park boundaries includeDeath Valley, the northern section ofPanamint Valley, the southern section ofEureka Valley and most ofSaline Valley.

The park occupies an interface zone between the aridGreat Basin andMojave deserts, protecting the northwest corner of the Mojave Desert and its diverse environment ofsalt-flats, sanddunes,badlands, valleys, canyons and mountains.

Death Valley is the largest national park in thecontiguous United States, as well as the hottest, driest and lowest of all the national parks in the United States.[5] It containsBadwater Basin, the second-lowest point in the Western Hemisphere and lowest inNorth America at 282 feet (86 m) below sea level. More than 93% of the park is a designatedwilderness area.[6]

The park is home to many species of plants and animals which have adapted to the harshdesert environment includingcreosote bush,Joshua tree,bighorn sheep,coyote, and the endangeredDeath Valley pupfish, a survivor from much wetter times.UNESCO included Death Valley as the principal feature of itsMojave and Colorado Deserts Biosphere Reserve in 1984.[7]

A series ofNative American groups inhabited the area from as early as 7000 BC, most recently theTimbisha around 1000 AD who migrated between winter camps in the valleys and summer grounds in the mountains. A group of European-Americans, lost in the valley in 1849 while looking for a shortcut to thegold fields of California, gave this valley its grim name, even though only one of their group died there.[8]

Several short-livedboom towns sprang up during the late 19th and early 20th centuries to mine gold and silver. The only long-term profitableore to be mined wasborax, which was transported out of the valley withtwenty-mule teams. The valley later became the subject of books, radio programs, television series, and movies. Tourism expanded in the 1920s when resorts were built aroundStovepipe Wells andFurnace Creek. Death Valley National Monument was declared in 1933 and the park was substantially expanded and became a national park in 1994.[3]

The natural environment of the area has been shaped largely by its geology. The valley is actually agraben with the oldestrocks being extensivelymetamorphosed and at least 1.7 billion years old.[9] Ancient, warm, shallow seas deposited marine sediments untilrifting opened thePacific Ocean. Additional sedimentation occurred until asubduction zone formed off the coast. The subductionuplifted the region out of the sea and created a line ofvolcanoes. Later thecrust started to pull apart, creating the currentBasin and Range landform. Valleys filled with sediment and, during the wet times ofglacial periods, with lakes, such asLake Manly.

Death Valley is the fifth-largest American national park and the largest in the contiguous United States. It is also larger than the states ofRhode Island andDelaware combined, and nearly as large asPuerto Rico.[10] In 2013, Death Valley National Park was designated as adark sky park by theInternational Dark-Sky Association.[11]

Geographic setting

[edit]

There are two major valleys in the park,Death Valley andPanamint Valley. Both of these valleys were formed within the last few million years and both are bounded by north–south-trendingmountain ranges.[12] These and adjacent valleys follow the general trend ofBasin and Range topography with one modification: there are parallelstrike-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 more subsidence there.

Uplift of surrounding mountain ranges and subsidence of the valley floor are both occurring. The uplift on the Black Mountains is so fast that thealluvial fans (fan-shaped deposits at the mouth of canyons) there are small and steep compared to the huge alluvial fans coming off thePanamint Range. Fast uplift of a mountain range in an arid environment often does not allow its canyons enough time to cut a classic V-shape all the way down to the stream bed. Instead, a V-shape ends at aslot canyon halfway down, forming a 'wine glass canyon.' Sediment is deposited on a small and steep alluvial fan.

At 282 feet (86 m) belowsea level at its lowest point,[13] Badwater Basin on Death Valley's floor is the second-lowest depression in the Western Hemisphere (behindLaguna del Carbón inArgentina), whileMount Whitney, only 85 miles (137 km) to the west, rises to 14,505 feet (4,421 m) and is the tallest mountain in thecontiguous United States.[12] This topographic relief is the greatest elevation gradient in thecontiguous United States and is the terminus point of theGreat Basin's southwestern drainage.[9] Although the extreme lack of water in the Great Basin makes this distinction of little current practical use, it does mean that in wetter times the lake that once filled Death Valley (Lake Manly) was the last stop for water flowing in the region, meaning the water there was saturated in dissolved materials. Thus, thesalt pans in Death Valley are among the largest in the world and are rich in minerals, such asborax and various salts andhydrates.[14] The largest salt pan in the park extends 40 miles (64 km) from theAshford Mill Site to the Salt Creek Hills, covering some 200 square miles (520 km2) of the valley floor.[14][note 1] The best knownplaya in the park is theRacetrack, known for its moving rocks.

Climate

[edit]
A cross section through the highest and lowest points in Death Valley National Park

According to theKöppen climate classification system, Death Valley National Park has a hot desert climate (BWh). Theplant hardiness zone at Badwater Basin is 9b with an average annual extreme minimum temperature of 28.0 °F (−2.2 °C).[15]

Death Valley is the hottest and driest place in North America due to its lack of surface water and low relief. It is so frequently the hottest spot in the United States that many tabulations of the highest daily temperatures in the country omit Death Valley as a matter of course.[16][17]

On the afternoon of July 10, 1913, theUnited States Weather Bureau recorded a high temperature of 134 °F (57 °C) atGreenland Ranch (nowFurnace Creek) in Death Valley.[18] This temperature stands as the highest ambient air temperature ever recorded at the surface of the Earth. (A report of a temperature of 58 °C (136 °F) recorded in Libya in 1922 was later determined to be inaccurate.)[19] Daily summer temperatures of 120 °F (49 °C) or greater are common, as well as below freezing nightly temperatures in the winter.[9] July is the hottest month, with an average high of 117 °F (47 °C) and an average low of 91 °F (33 °C). December is the coldest month, with an average high of 66 °F (19 °C) and an average low of 41 °F (5 °C). The record low is 15 °F (−9.4 °C). There are an average of 197.3 days annually with highs of 90 °F (32.2 °C) or higher and 146.9 days annually with highs of 100 °F (37.8 °C) or higher. Freezing temperatures of 32 °F (0 °C) or lower occur on an average of 8.6 days annually.

Several of the larger Death Valley springs derive their water from a regionalaquifer, which extends as far east as southernNevada andUtah. Much of the water in this aquifer has been there for many thousands of years, since thePleistocene ice ages, when theclimate was cooler and wetter. Today's drier climate does not provide enough precipitation to recharge the aquifer at the rate at which water is being withdrawn.[20]

Telescope Peak

The highest range within the park is the Panamint Range, withTelescope Peak being its highest point at 11,049 feet (3,368 m).[9] The Death Valley region is a transitional zone in the northernmost part of theMojave Desert and consists of five mountain ranges removed from the Pacific Ocean. Three of these are significant barriers: theSierra Nevada, theArgus Range, and the Panamint Range. Air masses tend to lose moisture as they are forced up over mountain ranges, in what climatologists call arainshadow effect.

The exaggeratedrain shadow effect for the Death Valley area makes itNorth America's driest spot, receiving about 1.5 inches (38 mm) of rainfall annually at Badwater, and some years fail to register any measurable rainfall.[21] Annual average precipitation varies from 1.92 inches (49 mm) overall below sea level to over 15 inches (380 mm) in the higher mountains that surround the valley.[22] When rain does arrive it often does so in intense storms that causeflash floods which remodel the landscape and sometimes create very shallow ephemeral lakes.[23]

Lake Badwater, March 2005

The hot, dry climate makes it difficult for soil to form.Mass wasting, the down-slope movement of loose rock, is therefore the dominant erosive force in mountainous areas, resulting in "skeletonized" ranges (mountains with very little soil on them).Sand dunes in the park, while famous, are not nearly as widespread as their fame or the dryness of the area may suggest. The Mesquite Flat dune field is the most easily accessible from the paved road just east of Stovepipe Wells in the north-central part of the valley and is primarily made ofquartz sand. Another dune field is just 10 miles (16 km) to the north but is instead mostly composed oftravertine sand.[24] The highest dunes in the park, and some of the highest in North America, are located in theEureka Valley about 50 miles (80 km) to the north of Stovepipe Wells, while thePanamint Valley dunes and theSaline Valley dunes are located west and northwest of the town, respectively. The Ibex dune field is near the seldom-visited Ibex Hill in the southernmost part of the park, just south of the Saratoga Springs marshland. All the latter four dune fields are accessible only via unpaved roads. Prevailing winds in the winter come from the north, and prevailing winds in the summer come from the south. Thus, the overall position of the dune fields remains more or less fixed.

There are rare exceptions to the dry nature of the area. In 2005, an unusually wet winter created a 'lake' in the Badwater Basin and led to the greatest wildflower season in the park's history.[25] In October 2015, a "1000 year flood event" with over three inches of rain caused major damage in Death Valley National Park.[26] A similar widespread storm in August 2022 damaged pavement and deposited debris on nearly every road, trapping 1,000 residents and visitors overnight.[27]

Climate data for Death Valley National Park, California, 1991–2020 normals,[a] extremes 1911–present
MonthJanFebMarAprMayJunJulAugSepOctNovDecYear
Record high °F (°C)90
(32)
97
(36)
103
(39)
113
(45)
122
(50)
129
(54)
134
(57)
130
(54)
127
(53)
114
(46)
98
(37)
89
(32)
134
(57)
Mean maximum °F (°C)78.4
(25.8)
85.1
(29.5)
95.4
(35.2)
106.0
(41.1)
113.6
(45.3)
122.0
(50.0)
125.9
(52.2)
123.4
(50.8)
118.1
(47.8)
106.2
(41.2)
90.0
(32.2)
77.8
(25.4)
126.7
(52.6)
Mean daily maximum °F (°C)67.2
(19.6)
73.7
(23.2)
82.6
(28.1)
91.0
(32.8)
100.7
(38.2)
111.1
(43.9)
117.4
(47.4)
115.9
(46.6)
107.7
(42.1)
93.3
(34.1)
77.4
(25.2)
65.6
(18.7)
92.0
(33.3)
Daily mean °F (°C)54.9
(12.7)
61.3
(16.3)
69.8
(21.0)
77.9
(25.5)
87.8
(31.0)
97.5
(36.4)
104.2
(40.1)
102.3
(39.1)
93.4
(34.1)
78.9
(26.1)
64.0
(17.8)
53.4
(11.9)
78.8
(26.0)
Mean daily minimum °F (°C)42.5
(5.8)
49.0
(9.4)
57.1
(13.9)
64.8
(18.2)
75.0
(23.9)
84.0
(28.9)
91.0
(32.8)
88.7
(31.5)
79.1
(26.2)
64.4
(18.0)
50.5
(10.3)
41.1
(5.1)
65.6
(18.7)
Mean minimum °F (°C)30.5
(−0.8)
36.1
(2.3)
42.8
(6.0)
49.8
(9.9)
58.5
(14.7)
67.9
(19.9)
78.3
(25.7)
75.3
(24.1)
65.4
(18.6)
49.5
(9.7)
35.9
(2.2)
29.0
(−1.7)
28.0
(−2.2)
Record low °F (°C)15
(−9)
20
(−7)
26
(−3)
35
(2)
42
(6)
49
(9)
62
(17)
65
(18)
41
(5)
32
(0)
24
(−4)
19
(−7)
15
(−9)
Averageprecipitation inches (mm)0.37
(9.4)
0.52
(13)
0.25
(6.4)
0.10
(2.5)
0.03
(0.76)
0.05
(1.3)
0.10
(2.5)
0.10
(2.5)
0.20
(5.1)
0.12
(3.0)
0.10
(2.5)
0.26
(6.6)
2.20
(56)
Average precipitation days(≥ 0.01 in)2.42.92.01.10.90.31.10.90.81.10.91.616.0
Source: NOAA[28][29]
Climate data for Death Valley (Cow Creek Station)
MonthJanFebMarAprMayJunJulAugSepOctNovDecYear
Record high °F (°C)84
(29)
89
(32)
100
(38)
110
(43)
120
(49)
125
(52)
126
(52)
125
(52)
123
(51)
111
(44)
95
(35)
84
(29)
126
(52)
Mean daily maximum °F (°C)64.4
(18.0)
71.6
(22.0)
80.6
(27.0)
90.9
(32.7)
100.0
(37.8)
109.3
(42.9)
116.0
(46.7)
113.8
(45.4)
106.9
(41.6)
92.1
(33.4)
75.4
(24.1)
65.9
(18.8)
90.6
(32.6)
Daily mean °F (°C)52.5
(11.4)
59.1
(15.1)
67.4
(19.7)
77.5
(25.3)
86.4
(30.2)
95.3
(35.2)
102.1
(38.9)
99.9
(37.7)
92.1
(33.4)
78.1
(25.6)
62.3
(16.8)
54.1
(12.3)
77.2
(25.1)
Mean daily minimum °F (°C)40.6
(4.8)
46.6
(8.1)
54.3
(12.4)
64.1
(17.8)
72.7
(22.6)
81.2
(27.3)
88.4
(31.3)
86.0
(30.0)
77.4
(25.2)
64.0
(17.8)
49.3
(9.6)
42.4
(5.8)
63.9
(17.7)
Record low °F (°C)19
(−7)
30
(−1)
33
(1)
45
(7)
52
(11)
54
(12)
69
(21)
69
(21)
57
(14)
40
(4)
32
(0)
27
(−3)
19
(−7)
Averageprecipitation inches (mm)0.24
(6.1)
0.32
(8.1)
0.20
(5.1)
0.20
(5.1)
0.10
(2.5)
0.02
(0.51)
0.10
(2.5)
0.11
(2.8)
0.12
(3.0)
0.11
(2.8)
0.20
(5.1)
0.29
(7.4)
2.00
(51)
Source:http://www.wrcc.dri.edu[30]

Human history

[edit]
Petroglyphs above Mesquite Springs

Early inhabitants and transient populations

[edit]

FourNative American cultures are known to have lived in the area during the last 10,000 years.[9] The first known group, theNevares Spring People, werehunters and gatherers who arrived in the area perhaps 9,000 years ago (7000 BC) when there were still small lakes in Death Valley and neighboring Panamint Valley.[31] A much milder climate persisted at that time, and large game animals were still plentiful. By 5,000 years ago (3000 BC) theMesquite Flat People displaced the Nevares Spring People.[31] Around 2,000 years ago theSaratoga Spring People moved into the area, which by then was probably already a hot, dry desert.[31][note 2] This culture was more advanced at hunting and gathering and was skillful at handcrafts. They also left mysterious stone patterns in the valley.

One thousand years ago, the nomadicTimbisha (formerly called Shoshone and also known as Panamint or Koso) moved into the area and hunted game and gatheredmesquite beans along withpinyon pine nuts.[9][31] Because of the wide altitude differential between the valley bottom and the mountain ridges, especially on the west, the Timbisha practiced a vertical migration pattern.[9] Their winter camps were located near water sources in the valley bottoms. As the spring and summer progressed and the weather warmed, grasses and other plant food sources ripened at progressively higher altitudes. November found them at the very top of the mountain ridges where they harvested pine nuts before moving back to the valley bottom for winter.

TheCalifornia Gold Rush brought the first people of European descent known to visit the immediate area. In December 1849 two groups ofCalifornia Gold Country-bound travelers with perhaps 100 wagons total stumbled into Death Valley after getting lost on what they thought was a shortcut off theOld Spanish Trail.[32] Called theBennett-Arcane Party, they were unable to find a pass out of the valley for weeks; they were able to find fresh water at various springs in the area, but were forced to eat several of their oxen to survive. They used the wood of their wagons to cook the meat and make jerky. The place where they did this is today referred to as "Burnt Wagons Camp" and is located near Stovepipe Wells.

After abandoning their wagons, they eventually were able to hike out of the valley. Just after leaving the valley, one of the women in the group turned and said, "Goodbye Death Valley," giving the valley its name.[32] Included in the party wasWilliam Lewis Manly whose autobiographical bookDeath Valley in '49 detailed this trek and popularized the area (geologists later named the prehistoric lake that once filled the valley after him).

Boom and bust

[edit]
Historical locomotive for transportingborax in Death Valley

The ores that are most famously associated with the area were also the easiest to collect and the most profitable: evaporite deposits such as salts,borate, andtalc. Borax was found by Rosie and Aaron Winters nearThe Ranch at Death Valley (then called Greenland) in 1881.[33] Later that same year, theEagle Borax Works became Death Valley's first commercial borax operation.William Tell Coleman built theHarmony Borax Works plant and began to process ore in late 1883 or early 1884, continuing until 1888.[34] This mining and smelting company produced borax to makesoap and for industrial uses.[35] The end product was shipped out of the valley 165 miles (266 km) to theMojave railhead in 10-ton-capacity wagons pulled by "twenty-mule teams" that were actually teams of 18 mules and two horses each.[35]

A twenty-mule team in Death Valley

The teams averaged two miles (3.2 km) an hour and required about 30 days to complete a round trip.[33] The trade name20-Mule Team Borax was established byFrancis Marion Smith'sPacific Coast Borax Company after Smith acquired Coleman's borax holdings in 1890. A memorable advertising campaign used the wagon's image to promote theBoraxo brand of granular hand soap and theDeath Valley Days radio and television programs. In 1914, theDeath Valley Railroad was built to serve mining operations on the east side of the valley. Mining continued after the collapse of Coleman's empire, and by the late 1920s the area was the world's number one source of borax.[9] Some four to six million years old, the Furnace Creek Formation is the primary source of borate minerals gathered from Death Valley's playas.[33]

Other visitors stayed to prospect for and mine deposits ofcopper,gold,lead, andsilver.[9] These sporadic mining ventures were hampered by their remote location and the harsh desert environment. In December 1903, two men from Ballarat were prospecting for silver.[36] One was an out-of-work Irish miner named Jack Keane and the other was a one-eyed Basque butcher named Domingo Etcharren. Quite by accident, Keane discovered an immense ledge of free-milling gold by the duo's work site and named the claim theKeane Wonder Mine. This started a minor and short-livedgold rush into the area.[36] The Keane Wonder Mine, along with mines atRhyolite,Skidoo andHarrisburg, were the only ones to extract enough metal ore to make them worthwhile. Outright shams such asLeadfield also occurred, but most ventures quickly ended after a short series of prospecting mines failed to yield evidence of significant ore (these mines now dot the entire area and are a significant hazard to anyone who enters them). The boom towns which sprang up around these mines flourished during the first decade of the 1900s, but soon declined after thePanic of 1907.[34]

Early tourism

[edit]

The first documented tourist facilities in Death Valley were a set of tent houses built in the 1920s where Stovepipe Wells is now located. People flocked to resorts built around natural springs thought to have curative and restorative properties. In 1927, Pacific Coast Borax turned the crew quarters of its Furnace Creek Ranch into a resort, creating theFurnace Creek Inn and resort.[37] The spring at Furnace Creek was harnessed to develop the resort, and as the water was diverted, the surroundingmarshes andwetlands started to shrink.[20]

Scotty's Castle under construction

Soon the valley was a popular winter destination. Other facilities started off as private getaways but were later opened to the public. Most notable among these was Death Valley Ranch, better known asScotty's Castle. This large ranch home built in theSpanish Revival style became a hotel in the late 1930s and, largely because of the fame ofDeath Valley Scotty, a tourist attraction. Death Valley Scotty, whose real name was Walter Scott, was a gold miner who pretended to be the owner of "his castle", which he claimed to have built with profits from his gold mine. Neither claim was true, but the real owner,Chicago millionaireAlbert Mussey Johnson, encouraged the myth. When asked by reporters what his connection was to Walter Scott's castle, Johnson replied that he was Mr. Scott's banker.[38]

Protection and later history

[edit]

PresidentHerbert Hoover proclaimed anational monument in and around Death Valley on February 11, 1933, setting aside almost two million acres (8,100 km2) of southeastern California and small parts of Nevada.[39]

Civilian Conservation Corps workers in Death Valley

TheCivilian Conservation Corps (CCC) developed infrastructure in Death Valley National Monument during theGreat Depression and on into the early 1940s. The CCC built barracks, graded 500 miles (800 km) of roads, installed water and telephone lines, and a total of 76 buildings. Trails in the Panamint Range were built to points of scenic interest, and anadobe village, laundry and trading post were constructed for theTimbisha Shoshone Tribe. Five campgrounds, restrooms, an airplane landing field and picnic facilities were also built.[40]

The creation of the monument resulted in a temporary closing of the lands to prospecting and mining. However, Death Valley was quickly reopened to mining byCongressional action in June 1933. As improvements in mining technology allowed lower grades of ore to be processed, and new heavy equipment allowed greater amounts of rock to be moved, mining in Death Valley changed. Gone were the days of the "single-blanket, jackass prospector" long associated with the romantic west.Open pit andstrip mines scarred the landscape as international mining corporations bought claims in highly visible areas of the national monument. The public outcry that ensued led to greater protection for all national park and monument areas in the United States.[34] In 1976, Congress passed the Mining in the Parks Act, which closed Death Valley National Monument to the filing of new mining claims, banned open-pit mining and required theNational Park Service to examine the validity of tens of thousands of pre-1976 mining claims. Mining was allowed to resume on a limited basis in 1980 with stricter environmental standards.[34] The last mine in the park, Billie Mine, closed in 2005.[41]

In 1952 President Harry Truman added theDevils Hole to Death Valley National Monument; it is the only habitat of theDevils Hole pupfish.[42][43]

Death Valley National Monument was designated abiosphere reserve in 1984.[3] On October 31, 1994, the monument was expanded by 1.3 million acres (5,300 km2) and re-designated as anational park, via congressional passage of theCalifornia Desert Protection Act (Public Law 103–433).[3] Consequently, the elevated status for Death Valley made it the largest national park in thecontiguous United States. On March 12, 2019, theJohn D. Dingell, Jr. Conservation, Management, and Recreation Act added 35,292 acres (55 sq mi; 143 km2) to the park.[44]

Many of the larger cities and towns within the boundary of the regionalgroundwater flow system that the park and its plants and animals rely upon are experiencing some of the fastest growth rates of any place in the United States. Notable examples within a 100-mile (160 km) radius of Death Valley National Park includeLas Vegas andPahrump, Nevada. In the case of Las Vegas, the local Chamber of Commerce estimates that 6,000 people are moving to the city every month. Between 1985 and 1995, the population of the Las Vegas Valley increased from 550,700 to 1,138,800.[20]

In 1977, parts of Death Valley were used by directorGeorge Lucas as afilming location forStar Wars, providing the setting for the fictional planetTatooine.[45][46]

Telescope and Wildrose Peaks from Emigrant Canyon Road

Geologic history

[edit]
EraRock Units/FormationsPrincipal Geologic Events
CenozoicAlluvial fans, stream, and playa deposits, dunes, numerous sedimentary, volcanic, and plutonic units in separate and interconnected basins and igneous fields (includes Artist Drive, Furnace Creek, Funeral, and Nova Formations).Major unconformity, continued deposition in modern Death Valley, opening of modern Death Valley, continuing development of present ranges and basins, onset of major extension.
MesozoicGranitic plutons, Butte ValleyThrust faulting and intrusion of plutons related to Sierra Nevada batholith; shallow marine deposition; unconformity.
PaleozoicResting spring Shale, Tin Mountain Limestone, Lost Burro,Hidden Valley Dolomite, Eureka Quartzite, Nopah, Bonanza King, Carrara, Zabriskie Quartzite, Wood Canyon.Development of a long-continuing carbonate bank on a passive continental margin; numerous intervals of emergence, interrupted by deposition of a blanket of sandstone in Middle Ordovician time. Deposition of a wedge of silliciclastic sediment during and immediately following the rifting along a new continental margin.
ProterozoicCrystalline basement, Pahrump, Stirling Quartzite, Johnnie, Ibex, Noonday Dolomite, Kingston Peak, Beck Spring, Crystal Spring.Regional metamorphism, Major unconformity, rapid uplift and erosion, shallow marine deposition, glacio-marine deposition, unconformity. Shallow to deep marine deposition along an incipient continental margin.
The Death Valley basin is filled with sediment (light yellow) eroded from the surrounding mountains. Black lines show some of the major faults that created the valley.
Main article:Geology of the Death Valley area

The park has a diverse and complex geologic history. Since its formation, the area that comprises the park has experienced at least four major periods of extensivevolcanism, three or four periods of majorsedimentation, and several intervals of majortectonic deformation where the crust has been reshaped. Two periods ofglaciation (a series of ice ages) have also had effects on the area, although noglaciers ever existed in the ranges now in the park.[47]

Basement and Pahrump Group

[edit]

Little is known about the history of the oldest exposedrocks in the area due to extensivemetamorphism (alteration of rock by heat and pressure).Radiometric dating gives an age of 1,700 million years for the metamorphism during theProterozoic.[9] About 1,400 million years ago a mass ofgranite now in the Panamint Range intruded this complex.[48] Uplift later exposed these rocks to nearly 500 million years of erosion.[48]

The Proterozoic sedimentaryformations of thePahrump Group were deposited on these basement rocks. This occurred following uplift and erosion of any earlier sediments from the Proterozoic basement rocks. The Pahrump is composed of arkoseconglomerate (quartz clasts in a concrete-like matrix) andmudstone in its lower part, followed bydolomite fromcarbonate banks topped byalgal mats asstromatolites, and finished with basin-filling sediment derived from the above, including possibleglacial till from the hypothesizedSnowball Earth glaciation.[49] The very youngest rocks in the Pahrump Group arebasaltic lava flows.

Rifting and deposition

[edit]
The Noonday Dolomite was formed as a carbonate shelf after the break-up ofRodinia.

Arift opened and subsequently flooded the region as part of the breakup of the supercontinentRodinia in theNeoproterozoic (by about 755 million years ago) and the creation of thePacific Ocean. A shoreline similar to the presentAtlantic Ocean margin of the United States lay to the east. Analgal mat-covered carbonate bank was deposited, forming the Noonday Dolomite.[50] Subsidence of the region occurred as thecontinental crust thinned and the newly formed Pacific widened, forming the Ibex Formation. An angularunconformity (an uneven gap in the geologic record) followed.

A trueocean basin developed to the west, breaking all the earlier formations along a steep front. A wedge of clastic sediment then began to accumulate at the base of the two underwater precipices, starting the formation of opposingcontinental shelves.[51] Three formations developed from sediment that accumulated on the wedge. The region's first knownfossils of complex life are found in the resulting formations.[51] Notable among these are theEdiacara fauna andtrilobites, the evolution of the latter being part of theCambrian Explosion of life.

The sandy mudflats gave way about 550 million years ago to a carbonate platform (similar to the one around the present-dayBahamas), which lasted for the next 300 million years ofPaleozoic time (refer to the middle of thetimescale image). Death Valley's position was then within ten or twenty degrees of the Paleozoicequator. Thick beds of carbonate-rich sediments were periodically interrupted by periods of emergence. Although details of geography varied during this immense interval of time, a north-northeastern coastline trend generally ran fromArizona up throughUtah. The resulting eight formations and one group are 20,000 feet (6 km) thick and underlay much of the Cottonwood, Funeral, Grapevine, and Panamint ranges.[51]

Compression and uplift

[edit]
TheLake Manly lake system as it might have looked during its last maximum extent 22,000 years ago[52] (USGS image)

In the early-to-mid-Mesozoic the western edge of the North American continent was pushed against the oceanic plate under the Pacific Ocean, creating asubduction zone.[51] A subduction zone is a type of contact between different crustal plates where heavier crust slides below lighter crust. Erupting volcanoes and uplifting mountains were created as a result, and the coastline was pushed to the west. TheSierran Arc started to form to the northwest from heat and pressure generated from subduction, and compressive forces causedthrust faults to develop.[53]

A long period of uplift and erosion was concurrent with and followed the above events, creating a major unconformity, which is a large gap in the geologic record. Sediments worn off the Death Valley region were carried both east and west by wind and water.[54] No Jurassic- toEocene-aged sedimentary formations exist in the area, except for some possibly Jurassic-agevolcanic rocks (see the top of thetimescale image).[54]

Stretching and lakes

[edit]
During very wet periods, theAmargosa River can flow at the surface, as it did in February 2005.

Basin and Range-associated stretching of large parts of crust below southwestern United States and northwestern Mexico started around 16 million years ago and the region is still spreading.[9] This stretching began to affect the Death and Panamint valleys area by 3 million years ago.[55] Before this, rocks now in the Panamint Range were on top of rocks that would become the Black Mountains and the Cottonwood Mountains. Lateral and vertical transport of these blocks was accomplished by movement on normalfaults. Right-lateral movement along strike-slip faults that run parallel to and at the base of the ranges also helped to develop the area.[56] Torsional forces, probably associated with northwesterly movement of thePacific plate along theSan Andreas Fault (west of the region), is responsible for the lateral movement.[55]

Igneous activity associated with this stretching occurred from 12 million to 4 million years ago.[56] Sedimentation is concentrated in valleys (basins) from material eroded from adjacent ranges. The amount of sediment deposited has roughly kept up with this subsidence, resulting in the retention of more or less the same valley floor elevation over time.[57]

Pleistocene ice ages started 2 million years ago, and melt from alpineglaciers on the nearby Sierra Nevada Mountains fed a series of lakes that filled Death andPanamint valleys and surrounding basins (see the top of thetimescale image). The lake that filled Death Valley was the last of a chain of lakes fed by theAmargosa andMojave Rivers, and possibly also theOwens River. The large lake that covered much of Death Valley's floor, which geologists callLake Manly, started to dry up 10,500 years ago.[58]Salt pans andplayas were created as ice age glaciers retreated, thus drastically reducing the lakes' water source. Only faint shorelines are left.

Biology

[edit]
Sphinx moth on arock nettle in Mosaic Canyon

Habitat varies fromsalt pan at 282 feet (86 m) below sea level to the sub-alpine conditions found on the summit of Telescope Peak, which rises to 11,049 feet (3,368 m).[59] Vegetation zones includecreosote bush,desert holly, andmesquite at the lower elevations andsage up throughshadscale,blackbrush,Joshua tree,pinyon-juniper, tolimber pine andbristlecone pine woodlands.[59] The salt pan is devoid of vegetation, and the rest of the valley floor and lower slopes have sparse cover, although where water is available, an abundance of vegetation is usually present.These zones and the adjacent desert support a variety of wildlifespecies, including 51 species of nativemammals, 307 species ofbirds, 36 species ofreptiles, 3 species ofamphibians, and 2 species of nativefish.[60]

Small mammals are more numerous than large mammals, such asbighorn sheep,coyotes,bobcats,kit foxes,cougars, andmule deer.[60] Mule deer are present in the pinyon/juniper associations of the Grapevine, Cottonwood, and Panamint ranges.[60] Bighorn sheep are a rare species of mountain-dwelling 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 andburros compete for habitat.

Death Valley pupfish spawning in Salt Creek

The ancestors of theDeath Valley pupfish swam to the area from theColorado River via a long-since dried-up system of rivers and lakes (seeLake Manly). They now live in two separate populations: one in Salt Creek and another in Cottonball Marsh. Death Valley is one of the hottest and driest places in North America, yet it is home to over 1,000 species ofplants; 23 of which, including the very rare rock lady (Holmgrenanthe), are not found anywhere else.[59]

Adaptation to the dry environment is key. For example, creosote bush and mesquite have tap-root systems that can extend 50 feet (15 m) down in order to take advantage of a year-round supply ofground water. The diversity of Death Valley's plant communities results partly from the region's location in a transition zone between theMojave Desert, theGreat Basin Desert and theSonoran Desert. This location, combined with the great relief found within the park, supports vegetation typical of three bioticlife zones: the lower Sonoran, the Canadian, and the arctic/alpine in portions of the Panamint Range. Based on the Munz and Keck (1968) classifications, seven plant communities can be categorized within these life zones, each characterized by dominant vegetation and representative of three vegetation types: scrub, desert woodland, and coniferous forest. Microhabitats further subdivide some communities into zones, especially on the valley floor.[61]

Unlike more typical locations across the Mojave Desert, many of the water-dependent Death Valley habitats possess a diversity of plant and animal species that are not found anywhere else in the world.[20] The existence of these species is due largely to a unique geologic history and the process ofevolution that has progressed in habitats that have been isolated from one another since thePleistocene epoch.[62]

Activities

[edit]
See also:Places of interest in the Death Valley area

Sightseeing is available by personal automobile,four-wheel drive, motorcycle,[63] bicycle,mountain bike (on established roadways only), andhiking.[64]State Route 190, the Badwater Road, the Scotty's Castle Road, and paved roads toDante's View and Wildrose provide access to the major scenic viewpoints and historic points of interest. More than 350 miles (560 km) of unpaved and four-wheel-drive roads provide access to wilderness hiking, camping, and historical sites.[65] Unlike many othernational parks in the U.S. there are no formal entrance stations, and instead entry fees can be paid at the visitor centers, ranger stations, or various fee machines around the park.[66] There are hiking trails of varying lengths and difficulties, but most backcountry areas are accessible only by cross-country hiking. The peak season for visiting the park is from October to May, avoiding summer extreme temperatures. Costumed living history tours of the historicScotty's Castle were suspended in October 2015 due to extensive flood damage to the buildings and grounds. It remains closed to the public.[67][27]

A tourist sliding down Star Dune in the Mesquite Flat dune field

There are nine designated campgrounds within the park, and overnight backcountry camping permits are available at the visitor center.[68]Xanterra Parks & Resorts owns and operates a private resort, the Oasis at Death Valley,[39] which comprises two separate and distinct hotels: the Inn at Death Valley is a four-star historic hotel, and the Ranch at Death Valley is a three-star ranch-style property reminiscent of the mining and prospecting days.Panamint Springs Resort is in the western part of the park. Death Valley Lodging Company operates theStovepipe Wells Resort under a concession permit. There are a few motels near entrances to the park, inShoshone,Death Valley Junction,Beatty, andPahrump.

Furnace Creek Visitor Center is located on CA-190 and includes exhibits and a film about the park's geology, climate, wildlife and natural history, as well as human history and pioneer experience.[69] During the winter season—November through April—rangers offer interpretive tours and a variety of walks, talks, and presentations about Death Valley cultural and natural history. TheDeath Valley Natural History Association [Wikidata] maintains a bookstore.

The northeast corner ofSaline Valley has several developedhot spring pools accessible by several hours' drive on unpaved roads or by flying apersonal aircraft to theChicken Strip—an unchartedairstrip a short walk from the springs.[70]

Death Valley National Park is a popular location forstargazing as it has one of the darkest night skies in the United States. Despite its remote location, air quality and night visibility are threatened by civilization. In particular,light pollution is introduced by nearbyLas Vegas.[71] The darkest skies are located in the northwest of the park;[72]Ubehebe Crater is aBortle class 1 or "excellent dark sky" site.[73] TheAndromeda Galaxy and theTriangulum Galaxy are visible to the unaided eye under these conditions, and the Milky Way casts shadows; optical phenomena such as zodiacal light or "false dawn" and gegenschein are also visible to the unaided eye under these conditions.[74][75] Most southern regions of the park are Bortle class 2 or "average dark sky" sites.[76]

A 360-degree panorama ofRacetrack Playa at night. TheMilky Way is visible as an arc in the center.

See also

[edit]

Notes

[edit]
  1. ^Mean maxima and minima (i.e. the highest and lowest temperature readings during an entire month or year) calculated based on data at said location from 1991 to 2020.

References

[edit]

Explanatory notes

[edit]
  1. ^Badwater, the Devils Golf Course, and Salt Creek are all part of the Death Valley Saltpan.
  2. ^The last known lake to exist in Death Valley likely dried up 3,000 years ago.

Citations

[edit]
  1. ^"Death Valley".protectedplanet.net. Protected Planet. RetrievedMay 29, 2020.
  2. ^"Listing of acreage – December 31, 2012"(XLSX). Land Resource Division, National Park Service. RetrievedMarch 16, 2014. (National Park Service Acreage Reports)
  3. ^abcdNational Park Index (2001–2003), p. 26
  4. ^"NPS Annual Recreation Visits Report". National Park Service. RetrievedJuly 25, 2023.
  5. ^"Death Valley National Park (U.S. National Park Service)". National Park Service.Archived from the original on January 26, 2017. RetrievedJanuary 26, 2017.
  6. ^"Backcountry Roads – Death Valley National Park". National Park Service. August 25, 2019.Archived from the original on November 12, 2020. RetrievedDecember 7, 2020.
  7. ^"Biosphere Reserve Information – United States of America – Mojave and Colorado Deserts".unesco.org.UNESCO. November 3, 2005. Retrieved June 22, 2018.
  8. ^Dotson, Danny."Research Guides: National Parks: Death Valley National Park".guides.osu.edu. RetrievedJune 3, 2024.
  9. ^abcdefghijkWright and Miller 1997, p. 611
  10. ^"National Park Service Acreage Reports". National Park Service. December 31, 2021. RetrievedFebruary 28, 2022.Acreage report for calendar year ending December 31, 2021. The leftmost column titled "Gross Area Acres" under the "Listing of Acreage" tab was utilized as the source.
  11. ^"Death Valley National Park (U.S.)".darksky.org. International Dark-Sky Association. n.d.Archived from the original on October 27, 2020. RetrievedDecember 7, 2020.
  12. ^abSharp 1997, p. 1
  13. ^"USGS National Elevation Dataset (NED) 1 meter Downloadable Data Collection from The National Map 3D Elevation Program (3DEP)". United States Geological Survey. September 21, 2015. Archived fromthe original on March 25, 2019. RetrievedSeptember 22, 2015.
  14. ^abWright and Miller 1997, p. 625
  15. ^"USDA Interactive Plant Hardiness Map".United States Department of Agriculture. Archived fromthe original on July 4, 2019. RetrievedJuly 3, 2019.
  16. ^Hickcox, David H., "Temperature extremes. (United States) (1996 Weather)",Weatherwise, February 1, 1997. Abstracthere
  17. ^Hickcox, David, "Temperature extremes. (daily maximum and minimum temperatures in the US)",Weatherwise, March 1, 1999; abstract atEncyclopedia.com
  18. ^"World Meteorological Organization World Weather/Climate Extremes Archive". Archived fromthe original on January 4, 2013. RetrievedJanuary 10, 2013.
  19. ^El Fadli, KI; et al. (September 2012)."World Meteorological Organization Assessment of the Purported World Record 58°C Temperature Extreme at El Azizia, Libya (13 September 1922)".Bulletin of the American Meteorological Society.94 (2): 199.Bibcode:2013BAMS...94..199E.doi:10.1175/BAMS-D-12-00093.1.
  20. ^abcdUSGS 2004, p. "Furnace Creek"
  21. ^Wright and Miller 1997, pp. 610–611
  22. ^USGS weather
  23. ^"Flash Floods of 2015 – Death Valley National Park (U.S. National Park Service)". National Park Service. RetrievedFebruary 3, 2018.
  24. ^Kiver 1999, p. 283
  25. ^"Death Valles Alive with Wildflowers". NBC News. Associated Press. March 14, 2005. RetrievedJuly 31, 2019.
  26. ^"After historic flooding, Death Valley gears up for 'a long, hard recovery'".Los Angeles Times. November 10, 2015. RetrievedMay 11, 2016.
  27. ^abWigglesworth, Alex; Ryan, Harriet (August 7, 2022)."Destructive rain in Death Valley and flooded Vegas casinos mark a summer of extreme weather".Los Angeles Times. RetrievedAugust 7, 2022.
  28. ^"NOWData – NOAA Online Weather Data".National Oceanic and Atmospheric Administration. RetrievedJune 12, 2021.
  29. ^"Summary of Monthly Normals 1991–2020".National Oceanic and Atmospheric Administration. RetrievedJune 12, 2021.
  30. ^WRCC."Western U.S. Climate Historical Summaries Weather". Desert Research Institute. RetrievedJune 3, 2009.
  31. ^abcdWallace 1978
  32. ^abKiver 1999, p. 277
  33. ^abcUSGS 2004, p. "Harmony Borax Works"
  34. ^abcdNPS website, "Mining"
  35. ^abNPS website, "Twenty Mule Teams"
  36. ^abNPS website, "People"
  37. ^NPS website, "Furnace Creek Inn"
  38. ^NPS website, "Johnson and Scotty Build a Castle"
  39. ^abNPS Visitor Guide
  40. ^NPS website, "Civilian Conservation Corps"
  41. ^"Mining in Death Valley – Death Valley National Park". National Park Service.Archived from the original on March 6, 2015. RetrievedOctober 29, 2021.
  42. ^Rivard, Katherine."The Extraordinary Lives of Death Valley's Endangered Devils Hole Pupfish".National Park Foundation. RetrievedSeptember 25, 2024.
  43. ^"Devils Hole – Death Valley National Park". National Park Service. RetrievedSeptember 25, 2024.
  44. ^"S.47 – John D. Dingell, Jr. Conservation, Management, and Recreation Act; Part III—National Park System additions; Sec. 1431. Death Valley National Park boundary revision".congress.gov. Retrieved June 16, 2019.
  45. ^Hearn, Marcus (2005).The Cinema of George Lucas. Foreword by Ron Howard. New York: Abrams. p. 109.ISBN 0-8109-4968-7.
  46. ^"Star Wars trek: Death Valley – April 2001".Star Wars Locations. RetrievedMarch 28, 2012.
  47. ^"USGS Changing Climates and Ancient Lakes".USGS Western Region Geology and Geophysics Science Center. December 18, 2009. RetrievedNovember 15, 2023.
  48. ^abWright and Miller 1997, p. 631
  49. ^Wright and Miller 1997, pp. 631–632
  50. ^Wright and Miller 1997, p. 632
  51. ^abcdWright and Miller 1997, p. 634
  52. ^Kiver 1999, p. 281
  53. ^Barth, A.P. (August 1, 2011)."Birth of the Sierra Nevada magmatic arc: Early Mesozoic plutonism and volcanism in the east-central Sierra Nevada of California".Geological Society of America. 7 (4) (2011):877–897 – via Geoscience World.
  54. ^abWright and Miller 1997, p. 635
  55. ^abKiver 1999, p. 278
  56. ^abWright and Miller 1997, p. 616
  57. ^"Death Valley Geology". National Park Service. January 9, 2022. RetrievedNovember 15, 2023.
  58. ^Sharp 1997, p. 41
  59. ^abcNPS website, "Plants"
  60. ^abcNPS website, "Animals"
  61. ^"NPS Death Valley General Management Plan". National Park Service. November 15, 2023. RetrievedNovember 15, 2023.
  62. ^"National Park Service Death Valley Geologic Formations". National Park Service. September 29, 2021. RetrievedNovember 15, 2023.
  63. ^Joe Berk (September–October 2008)."Death Valley by motorcycle". Motorcycle Classics. RetrievedAugust 6, 2009.
  64. ^"Outdoor Activities". National Park Service. April 21, 2019. RetrievedFebruary 14, 2020.
  65. ^NPS 2002, p. 55
  66. ^"Death Valley National Park Fees & Passes". National Park Service. RetrievedDecember 31, 2021.
  67. ^Death Valley National Park – Flash Floods of 2015,National Park Service
  68. ^NPS website, "Campgrounds"
  69. ^NPS website, "Ranger Programs"
  70. ^"Chicken Strip Reopens | Recreational Aviation Foundation".theraf.org. Archived fromthe original on February 4, 2016. RetrievedApril 19, 2018.
  71. ^NPS website, "Lightscape / Night Sky"
  72. ^"Death Valley". caglow.com. Archived fromthe original on June 12, 2020. RetrievedJanuary 4, 2011.
  73. ^"Light pollution map".lightpollutionmap.info. RetrievedJuly 13, 2018.
  74. ^"bortle dark sky scale".handprint.com. RetrievedJuly 13, 2018.
  75. ^"A Challenge in Visual Athletics: Hunting the Gegenschein – Universe Today".Universe Today. February 3, 2016. RetrievedJuly 13, 2018.
  76. ^"Light pollution map".lightpollutionmap.info. RetrievedJuly 13, 2018.

Bibliography

[edit]

Public Domain This article incorporatespublic domain material from websites or documents of theNational Park Service.
Public Domain This article incorporatespublic domain material from websites or documents of theUnited States Geological Survey.

  • Kiver, Eugene P.; David V. Harris (1999).Geology of U.S. Parklands (Fifth ed.). New York: John Wiley & Sons.ISBN 978-0-471-33218-3.
  • National Park Service (2001–2003).The National Parks Index(PDF). Washington, D.C.: U.S. Department of the Interior. Archived fromthe original(PDF) on July 13, 2007. RetrievedOctober 5, 2008.
  • National Park Service (April 2002).Death Valley General Management Plan(PDF). Washington, D.C.: U.S. Department of the Interior. RetrievedSeptember 28, 2008.
  • National Park Service.Death Valley National Park Visitor Guide 2008/2009(PDF). U.S. Department of the Interior. RetrievedSeptember 28, 2008.
  • National Park Service."Death Valley National Park website". U.S. Department of the Interior. RetrievedSeptember 17, 2008. (adapted public domain text)
  • Rothman, Hal K., and Char Miller.Death Valley National Park: A History (University of Nevada Press; 2013) 216 pages; an environmental and human history
  • Sharp, Robert P.; Allen F. Glazner (1997).Geology Underfoot in Death Valley and Owens Valley. Missoula, Montana: Mountain Press Publishing Company.ISBN 978-0-87842-362-0.
  • "Death Valley National Park Virtual Geology Field Trip". United States Geological Survey. January 13, 2004. Archived fromthe original on September 22, 2008. RetrievedSeptember 16, 2008. (adapted public domain text)
  • "Death Valley's Incredible Weather". United States Geological Survey. January 13, 2004. Archived fromthe original on June 1, 2008. RetrievedOctober 5, 2008.
  • Wallace, William James; Edith Wallace (1978).Ancient Peoples and Cultures of Death Valley National Monument. Ramona, CA: Acoma Books.ISBN 978-0-916552-12-1.
  • Wright, Laureen A.; Miller, Martin G. (1997). "Chapter 46: Death Valley National Park, Eastern California and southwestern Nevada". In Ann G. Harris (ed.).Geology of National Parks (Fifth ed.). Dubuque, IA: Kendall/Hunt Publishing. pp. 610–637.ISBN 978-0-7872-1065-6.

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