Zion National park

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(Texts copied from the Zion National Park Wikipedia article)

Zion National Park is a United States National Park located in the Southwestern United States, near Springdale, Utah. A prominent feature of the 229-square-mile (593 km²) park is Zion Canyon, 15 miles (24 km) long and up to half a mile (800 m) deep, cut through the reddish and tan-colored Navajo Sandstone by the North Fork of the Virgin River. Located at the junction of the Colorado Plateau, Great Basin, and Mojave Desert regions, this unique geography and variety of life zones allow for unusual plant and animal diversity. A total of 289 bird species, 75 mammals (including 19 species of bat), 32 reptiles and numerous plant species inhabit the park's four life zones: desert, riparian, woodland, and coniferous forest. Notable megafauna include Mountain Lions, Mule Deer and Golden Eagles, along with reintroduced California Condors and Bighorn Sheep. Common plant species include Cottonwood, Cactus, Datura, Juniper, Pine, Boxelder, Sagebrush and various willows. Human habitation of the area started about 8,000 years ago with small family groups of Native Americans; the semi-nomadic Basketmaker Anasazi (300 CE) stem from one of these groups. In turn, the Virgin Anasazi culture (500 CE) developed as the Basketmakers settled in permanent communities. A different group, the Parowan Fremont, lived in the area as well. Both groups moved away by 1300 and were replaced by the Parrusits and several other Southern Paiute subtribes. The canyon was discovered by Mormons in 1858 and was settled by that same group in the early 1860s. Mukuntuweap National Monument was established in 1909 to protect the canyon, and by 1919 the monument was expanded to become Zion National Park (Zion is an ancient Hebrew word meaning a place of refuge or sanctuary). The Kolob section was proclaimed a separate Zion National Monument in 1937, but was incorporated into the park in 1956. The geology of the Zion and Kolob canyons area includes nine formations that together represent 150 million years of mostly Mesozoic-aged sedimentation. At various periods in that time, warm, shallow seas, streams, ponds and lakes, vast deserts and dry near-shore environments covered the area. Uplift associated with the creation of the Colorado Plateaus lifted the region 10,000 feet (3000 m) starting 13 million years ago.

Geography and Climate

The park is located in southwestern Utah in Washington, Iron, and Kane counties. Geomorphically, it is located on the Markagunt and Kolob plateaus, at the intersection of three North American geographic provinces: The Colorado Plateaus, the Great Basin, and the Mojave Desert. The northern part of the park is known as the Kolob Canyons section and is accessible from Interstate 15, exit 40. The 8,726 foot (2660 m) summit of Horse Ranch Mountain (photo) is the highest point in the park; the lowest point is the 3,666 foot (1117 m) elevation of Coal Pits Wash, creating a relief of about 5,100 feet (1500 m). Streams in the area follow rectangular paths because they follow jointing planes in the rocks. The headwaters of the Virgin River are at about 9,000 feet (2700 m) and the river empties into Lake Mead 200 miles (320 km) southeast after flowing 8,000 feet (2400 m) downward. This gives the Virgin a stream gradient that ranges from 50 to 80 feet per mile (0.9–1.5%)—one of the steepest stream gradients in North America. The road into Zion Canyon is 6 miles long, ending at the Temple of Sinawava ("Sinawava" refers to the Coyote God of the Paiute Indians[1][2]). At the Temple, the canyon narrows and a foot-trail continues to the mouth of the Zion Narrows, a spectacular gorge with walls 40–100 feet (12–30 meters) wide and 1000 feet (300 m) tall. The Zion Canyon road is served by a free shuttle bus from early April to late October and by private vehicles the other months of the year. Other roads in Zion are open to private vehicles year-round. Other areas of the park also offer outstanding scenery. The east side of the park is served by the Zion-Mount Carmel Highway which passes through the Zion-Mount Carmel Tunnel and ends at Mt. Carmel Junction. On the east side of the park notable park features include Checkerboard Mesa and the East Temple and one of the more popular hikes, the Canyon Overlook Trail. West of Zion Canyon, the Kolob Terrace area features The Subway, a famous slot canyon hike, and Lava Point, with a spectacular view of the entire area. The Kolob Canyons section, further west near Cedar City, features one of the world's longest arches, Kolob Arch.

Spring weather is unpredictable, with stormy, wet days being common, mixed with occasional warm, sunny weather. Precipitation is heaviest in March. Spring wildflowers bloom from April through June, peaking in May. Fall days are usually clear and mild; nights are often cool. Summer days are hot (95 °F to 110 °F; 35 °C to 43 °C), but overnight lows are usually comfortable (65 °F to 70 °F; 18 °C to 21 °C). Afternoon thunderstorms are common from mid-July through mid-September. Storms may produce waterfalls as well as flash floods. Autumn tree-color displays begin in September in the high country; inside Zion Canyon, autumn colors usually peak in late October. Winter in Zion Canyon is fairly mild. Winter storms bring rain or light snow to Zion Canyon and heavier snow to the higher elevations. Clear days may become quite warm, reaching 60 °F (16 °C); nights are often 20 °F to 40 °F (−7 °C to 4 °C). Winter storms can last several days and make roads icy. Zion roads are plowed, except the Kolob Terrace Road and the Kolob Canyons Road, which are closed when covered with snow. Winter driving conditions persist from November through March.

Geology

The nine known exposed formations visible in Zion National Park are part of a super-sequence of rock units called the Grand Staircase; they represent about 150 million years of mostly Mesozoic-aged sedimentation in that part of North America. The formations exposed in the Zion area were deposited as sediment in very different environments: • The warm, shallow (sometimes advancing or retreating) sea of the Kaibab and Moenkopi formations; • Streams, ponds, and lakes of the Chinle, Moenave, and Kayenta formations; • The vast desert of the Navajo and Temple Cap formations; and • The dry near-shore environment of the Carmel Formation. Uplift affected the entire region, known as the Colorado Plateaus, by slowly raising these formations more than 10,000 feet (3,000 m) higher than where they were deposited. This steepened the stream gradient of the ancestral Virgin and other rivers on the plateau.

The fast-moving streams took advantage of uplift-created joints in the rocks to remove all Cenozoic-aged formations and cut gorges into the plateaus. Zion Canyon was cut by the North Fork of the Virgin River in this way. During the later part of this process, lava flows and cinder cones covered parts of the area. High water volume in wet seasons does most of the downcutting in the main canyon and carries much of the 3 million tons of rock and sediment that the Virgin River transports yearly. The Virgin cuts away its canyon faster than its tributaries can cut away their own streambeds, so tributaries end in waterfalls from hanging valleys where they meet the Virgin. The valley between the peaks of the Twin Brothers is a notable example of a hanging valley in the canyon.