Yellowstone national park

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  • Přidal/a: anonymous
  • Datum přidání: 23. července 2006
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Yellowstone national park

Yellowstone National Park is the most famous national park in the United States. It is situated in northwestern Wyoming and partly in southern Montana and eastern Idaho. It was established in 1872 as the first national park of United States. With its 898 315 hectares' area is Yellowstone the largest national park of the country. It lies mostly on volcanic plateaus at 2300 to 2700 m above sea level, surrounded by Custer, Shoshone, Teton, Targhee, Beaverhead, and Gallatin national forests. It has more than 800 km of roads and more than 1600 km of trails. The John D. Rockefeller, Jr., Memorial Parkway, an 130-kilometre scenic roadway established in 1972 connects Yellowstone with Grand Teton National Park.

Yellowstone has many notable features, including rugged mountains, fossil forests, eroded lava flows, a black obsidian (volcanic-glass) mountain, and other geological formations, but biggest attractions are its 10 000 geysers, Mammoth Hot Springs, mud volcanoes, and lesser thermal phenomena. Many of the geysers erupt to heights of 30 meters or more.

Probably the most famous geyser of Yellowstone is "Old Faithful". It lies at the head of the Upper Geyser Basin in Yellowstone. It was so named in 1870 by the Washburn-Langford-Doane Expedition because it seemed to erupt "faithfully" every 65 to 70 minutes. Under a continuous observation, however it has been found that the eruptions occur quite irregularly with intervals from 33 to 148 minutes. These are understandably the extremes, on the average the Old Faithful erupts every 60 minutes. In every eruption there are about 45 000 l of hot water plus billowing steam ejected to height of about 52 m and the column stands for approximately 4 minutes. Geologists place the age of the geyser at 200-300 years.

I will explain now, what a mud volcano is. A mud volcano is a mound of mud heaved up through overlying sediments. The craters are usually shallow and may intermittently erupt mud. These eruptions continuously rebuild the cones, which are eroded relatively easily.

There are two types of mud volcanoes.

Some mud volcanoes are created by hotspring activity, where large amounts of gas and small amounts of water react chemically with surrounding rocks and form boiling mud.

Other mud volcanoes entirely of nonigneous origin occur only in oil-field regions that are relatively young and have soft, unconsolidated formations.

Under compactional stress, methane and related hydrocarbon gases mixed with mud force their way upward and burst through to the surface, spewing mud into a conelike shape. Because of the compactional stress and the depth from which the mixture comes, the mud is often hot and may have an accompanying steam cloud.

Yellowstone is also known for its lakes and rivers, which are stock with fish; especially trout is very popular with anglers. Among these are Yellowstone Lake, Shoshon Lake, and from rivers for example the Snake River, and the Yellowstone River.

Yellowstone Lake has 360 km2 of surface area, maximum depth of 90 m , is 32 km long, and 23 km wide and it lies at 2 356 m above sea level. It is the largest water body in North America at so high an altitude. It is fed and drained by the Yellowstone River. Yellowstone Lake has a shoreline of 175 km and is a really haven for rare species of water birds, for example trumpeter swans or Canadian geese and is prized for trout fishing.

Yellowstone River is well known for its scenic beauty. It rises in Yount Peak in Wyoming. It feeds into Yellowstone Lake below which it plunges 129 m in two spectacular waterfalls and then enters the Grand Canyon of the Yellowstone. The river was first explored in 1806 by Lieutenant William Clark, who sailed it down on his return journey from the Pacific. The firs trading post on the Yellowstone river wax established by Manuel Lisa, an indian trader, at the mouth of the Bighorn River in 1807.

Most of the park is forested, characteric tree is lodgepole pine. In valleys grow sagebrush and rabbit brush, and in warm months you can see wildflowers blossoms in Yellowstone. Unfortunately there was a disastrous series of forest fires in 1988 and large areas of park are burnt out now.

Animal life in Yellowstone is typical of the Rocky Mountains and includes buffalo, elk, deer, moose, bears, and coyotes. Rodents and other small mammals are also common. There are hundreds of different birds' species in the park, among them many waterfowl.

The Yellowstone is a nice place, like mostly all national parks are, but I'm afraid that has no importance. What is the meaning of national parks which cover hardly few per cent of Earth's surface, when the rest of the Earth is continuously destroyed by humans? That could be a good joke. I think that national parks are established mostly for conscience. What will be the meaning of few oases of life amid a destroyed Earth? What I'm really looking forward is the day, when there will be no need for national parks or any other parks, because people will respect and value the nature.

That will probably not be in my life, but it must happen one day or people will die with the Earth. We must recognize that this is the only Earth we have and when we destroy the Earth, we destroy us as well.



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