Mountain
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A mountain is a natural rise of the earth's surface having considerable mass, generally narrow sides, and a height greater than that of 100ft or higher. The height of mountains is measured as distance above sea level. They are formed when rock layers are squeezed from opposite sides when forces within earth push up crust. Mountains also form when some rock blocks move up and others move down. They can be found in both water and land areas. A mountain range is a large group of mountains.
The tallest mountain in the solar system is Olympus Mons (27 km) on Mars. The tallest mountain in the world is Mount Everest (8,848m) in Asia. The tallest mountain in North America is Mount McKinley (6,194m) in Alaska in the USA. The tallest in South America is Aconcagua (6,962m) in Argentina. For Africa, it is Kilimajaro (5,963m) of Tanzania. In Europe, the tallest mountain is in Russia called Elbrus (5,633m). Antarctica's tallest mountain is Vinsin Massiff (5,140m). In Oceania, a mountain called Puncak Jaya (5,030m) is the tallest there. This particular mountain is in Papua New Guinea / Indonesia.
[edit] Mountain types
There are five main types of mountains: volcanic, domed, folded, plateau, and fault-block. Some people say there are five types, as domed mountains can be a plutonic dome or a tectonic dome.
Volcanic mountains are mountains that form when molten rock erupts onto the earth's surface. They can either form on land or in the ocean. The Cascade Range in Washington, Oregon and northern California is composed of volcanic mountains. Some of the largest volcanic mountains are found along divergent boundaries, which form the mid-ocean ridges. The mid-ocean ridges have huge volcanic mountain chains that run through the Atlantic, Pacific and Indian Oceans. The mountains in the mid-ocean ridges can actually grow tall enough to create islands such as Iceland or the Azores.
Other volcanic mountains can form over hot spots, which are pockets of magma beneath the crust that erupt onto earth's surface. The Hawaiian Islands are actually the tops of really high volcanic islands that have formed over a hot spot on the sea floor. The main Hawiian island is actually a volcano that is about 9 km above the ocean floor, with a base that is about 160 km wide. Almost 4 km of this island is above sea level. In fact, a new Hawaiian island is forming right now!
Domed mountains, like those in the Black Hills of South Dakota and the Adirondack Mountains of New York, are an unusual type of mountain that is formed when molten rock rises through the crust and push up the rock layers above it. This creates a circular dome on the earth's surface. The molten rock eventually cools off and forms hardeded rock. When the pushed up rocks are worn away, the hardeded rock exposed. This exposed rock then wears away in places, leaving separate high peaks, or dome mountains.
Folded mountains make up some of the highest mountains in the world. Folded mountains commonly form along converging boundaries, where 2 continents are colliding. They tend to look like an accordion. Some really complex folds can be found in parts of the Alps, Himalayas, Appalachians, and Russia's Ural Mountains. These long mountain chains also show extensive signs of folding.
Plateau mountains are formed similar to folded mountains. They are large areas of flat topped rocks that have been lifted high above the crust by converging continental plates. Most plateaus are found near folded mountains. An example would be, the Tibetan Plateau, which is next to the Himalayan mountains.
Finally, fault block mountains are formed when parts of the earth's crust has been broken off into large blocks. These blocks are then lifted above the crust. Then, faulting tilts these blocks. The Sierra Nevada mountains, in California, are fault block mountains. The desert cities in the U.S., like Nevada, Arizona, western Utah, southern Oregon, southeastern California, and northern New Mexico.fault block mountains are formed when two simultaneous blocks of land rise above or fall down leaving its middle part behnd.
A more Universal classification of Mountain Ranges: 1. 'Volcanic Mountains' - formed behind a subduction zone on the continental crust. 2. 'Domed Mountains' - formed when magma pushes up and forces top layers of rock (elastic) up with it. 3. 'Folded Mountains' - At the collision of two contiental crusts, similar densities force rocks together, and build upwards. 4. 'Fault block' - similar to Domed mountains, although have broken (plasic) and move up as a 'chunk'. 5. 'M.O.R'- Mid Ocean Ridge, the area of sea floor spreading, lines of volcanoes.
A fault block mountain is a mountain or range formed as a horst when it was elevated between parallel normal faults. A horst is the raised fault block bounded by normal faults.
