White Sands National Monument

The White Sands National Monument [ ˌ waɪt sændz -] ( German White sand ) is a 25 km southwest of Alamogordo (New Mexico) nature reserve located on the northern end of the Chihuahuan Desert. It covers in a wide valley - the Tularosa Basin ( Tularosa Basin ) - the southern part of a 712 km ² gypsum field on which huge dunes have formed.

Tularosa Basin

The gypsum from which the White Sands is, lay at the bottom of a shallow sea that covered this area 250 million years ago. Finally, the plaster was to - enriched with marine deposits - stone, which was raised to around 70 million years ago when the Rocky Mountains formed into a gigantic dome. Prior to around ten million years, the center of this dome began to collapse and formed henceforth the Tularosa Basin. The remaining edges of the sagging dome formation now form the San Andres and Sacramento Mountains.

Genesis

White Sands

The gypsum ( calcium sulfate dihydrogenated ) is a mineral found near the top of the San Andres and Sacramento Mountains. He was resolved over time through snow and rain out of the rocks by the uplift of the mountains. Then he reached into the Tularosa Basin, where he was successively deposited as sediment. This would normally be carried by rivers into the sea, but as there is no drain in the Tularosa Basin, the gypsum and other dissolved sediment is trapped within the valley. After the water evaporated from the sediment, crystallized from the plaster. The crystals were broken in turn into grains that have been piled up by the wind to enormous white, dusty dunes.

One of the lowest points of the valley is a large dry lake, which temporarily fills with water: the Lake Lucero. Once the water evaporates again, dissolved gypsum accumulated on the surface.

During the last ice age there was more gypsum deposits, as a large lake - the Lake Otero - covered most of the valley. He dried off and left a large alkaline level.

Dunes

During wet weather periods when the water evaporates slowly, the gypsum deposited at the bottom of a dry lake in crystalline form from, known as selenite. Along the shoreline of Lake Lucero and Alkali - level cover layers of Selenitkristallen the ground, some up to a meter long. The forces of nature, heat, cold and humidity and dryness finally break the crystals into small sand particles that are light enough to be carried by the wind.

Strong winds blow across the dry lake, take gypsum particles and carry them with you. When the grains of sand dunes to accumulate, they collide against the gently curved, windward side of the dune location and produce small waves on the surface. On the steep crest of the dune, the sand builds up until lets him slip off the force of gravity; thus, the dune moves forward.

In White Sands, there are four different types of dunes:

  • Dome-shaped dunes: the first dunes, the windward form of Lake Lucero, are low sandy hills, which move up to ten meters a year.
  • Barchan dunes: crescent-shaped dunes form in areas of high wind, which brings only limited new sand to.
  • Diagonal dunes: In areas that are sufficiently supplied with sand, is crescent-shaped dunes together and form long chains of mountains of sand.
  • Parabolic dunes: Along the edges of the dune field anchor plants the foothills of the crescent-shaped dunes with each other and return to their shape.

Flora and Fauna

Even plants and animals that are well- equipped for life in the desert, have problems to survive in the changing world of the dunes. A small number of plants has changed in amazing ways and adapted and can prevent to be constantly buried under sand. The Soap Tree Yucca extended their tribe, so that their leaves are always above the sand and grows in this way up to 30 inches per year. Other plants hold a portion of the dune firmly to their roots and can continue to grow on the so- anchored sand base, while continuing to move the dune.

As in other deserts also keep most of the animals that live here during the heat of the day in their burrows under the earth, and only come out at night. In the morning, you can find traces of rodents, rabbits, foxes, coyotes, tree Stach learning and other nocturnal animals in the sand. Lizards, beetles and birds are diurnal and can be observed in the plant areas. A few species such as a pocket mouse, two species of lizards and various insects have developed a white camouflage that protects them from their enemies.

National Monument

Starting from the visitor center at the entrance of the National Monuments leads the Dunes Drive twelve kilometers into the midst of the dunes, from where they can be explored via four marked trails on foot. In summer, guided tours are also offered by the rangers. About once or twice a week, the park is blocked for security reasons, when in the White Sands Missile Range ( White Sands missile base ) surrounding the park missile tests are performed.

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