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Death Valley National Park (USA, California)

Death Valley National Park

Death Valley National Park

Death Valley National Park is located east of the Sierra Nevada in the arid Great Basin of the United States. Parts of the park are in southern Inyo County and northern San Bernardino County in Eastern California, with a small extension into southwestern Nye County and extreme southern Esmeralda County in Nevada. In addition, there is an exclave (Devil’s Hole) in southern Nye County. The park covers 5,262 square miles (13,630 km2), encompassing Saline Valley, a large part of Panamint Valley, almost all of Death Valley, and parts of several mountain ranges. Death Valley National Monument was declared a U.S. National Monument in 1933, placing the area under federal protection. In 1994, the monument was redesignated a national park, as well as being substantially expanded to include Saline and Eureka valleys. It is the hottest and driest of the national parks in the United States. The second-lowest point in the Western Hemisphere is in Badwater Basin, which is 282 feet (86 m) below sea level.

Mining was the primary activity in the area before it was protected. The first documented non-Native Americans to enter Death Valley did so in the winter of 1849, thinking they would save time by taking a shortcut to the gold fields of California. They were stuck for weeks and in the process gave the valley its name, even though only one of their group died there. Several short-lived boom towns sprang up during the late 19th and early 20th centuries to exploit minor local bonanzas of gold. The only long-term profitable ore to be mined, however, was borax, a mineral used to make soap and an important industrial compound. Today, borax is an essential component of high-temperature resistant boro-silicate glass products, for example Pyrex cookware. Twenty-mule teams were used to transport ore out of the valley; helping to make it famous and the subject of books, radio programs, television series, and movies.

The natural environment of the area has been shaped largely by its geology. The valley itself is actually a graben. The oldest rocks are extensively metamorphosed and at least 1.7 billion years old. Ancient warm, shallow seas deposited marine sediments until rifting opened the Pacific Ocean. Additional sedimentation occurred until a subduction zone formed off the coast. This uplifted the region out of the sea and created a line of volcanoes. Later the crust started to pull apart, creating the current Basin and Range landform. Valleys filled with sediment and, during the wet times of glacial periods, with lakes, such as Lake Manly.

There are two major valleys in the park, Death Valley and Panamint Valley. Both of these valleys were formed within the last few million years and both are bounded by north–south-trending mountain ranges. These and adjacent valleys 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 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 the alluvial fans (fan-shaped deposits at the mouth of canyons) there are small and steep compared to the huge alluvial fans coming off the Panamint 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 a slot canyon halfway down, forming a ‘wine glass canyon.’ Sediment is deposited on a small and steep alluvial fan.

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

The exaggerated rainshadow effect for the Death Valley area makes it North America’s driest spot, receiving about 1.5 inches (38 mm) of rainfall annually at Badwater (some years fail to register any measurable rainfall). 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. When rain does arrive it often does so in intense storms that cause flash floods which remodel the landscape and sometimes create very shallow ephemeral lakes.

At 282 feet (86 m) below sea level, Badwater Basin on Death Valley’s floor is the second-lowest point in the Western Hemisphere (behind Laguna del Carbón in Argentina), while Mount Whitney, only 85 miles (137 km) to the west, rises to 14,505 feet (4,421 m). This topographic relief is the greatest elevation gradient in the contiguous United States and is the terminus point of the Great Basin’s southwestern drainage. 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 the salt pans in Death Valley are among the largest in the world and are rich in minerals, such as borax and various salts and hydrates. The largest salt pan in the park extends 40 miles (64 km) from the Ashford Mill Site to the Salt Creek Hills, covering some 200 square miles (520 km2) of the valley floor. The best known playa in the park is the Racetrack, known for its moving rocks.

On July 10, 1913, a record 134 °F (56.7 °C) was measured at the Weather Bureau’s observation station at Greenland Ranch (now the site for the Furnace Creek Inn), the highest temperature ever recorded on that continent as of 2007. Several of the larger Death Valley springs derive their water from a regional aquifer, which extends as far east as southern Nevada and Utah. Much of the water in this aquifer has been there for many thousands of years, since the Pleistocene ice ages, when the climate 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.

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 area, resulting in “skeletonized” ranges (mountains with very little soil on them). Sand dunes in the park, while famous, are not nearly as numerous as their fame or the dryness of the area may suggest. One of the main dune fields is near Stovepipe Wells in the north-central part of the valley and is primarily made of quartz sand. Another dune field is just 10 miles (16 km) to the north but is instead mostly composed of travertine sand.

Four Native American cultures are known to have lived in the area during the last 10,000 years or so. The first known group, the Nevares Spring People, were hunters and gatherers who arrived in the area perhaps 9,000 years ago (7000 BCE) when there were still small lakes in Death Valley and neighboring Panamint Valley. A much milder climate persisted at that time, and large game animals were still plentiful. By 5,000 years ago (3000 BCE) the Mesquite Flat People displaced the Nevares Spring People. Around 2,000 years ago the Saratoga Spring People moved into the area, which by then was probably already a hot, dry desert. 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 nomadic Timbisha (formerly called Shoshone and also known as Panamint or Koso) moved into the area and hunted game and gathered mesquite beans along with pinyon pine nuts. 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. 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.

The California Gold Rush brought the first people of European descent known to visit the immediate area. In December 1849 two groups of California Gold Country-bound white travelers with perhaps 100 wagons total stumbled into Death Valley after getting lost on what they thought was a shortcut off the Old Spanish Trail. Called the Bennett-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 “Burned Wagons Camp” and is located near the sand dunes.

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 they endured its name. Included in the party was William Lewis Manly whose autobiographical book Death Valley in ’49 detailed this trek and popularized the area (geologists later named the prehistoric lake that once filled the valley after him).

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