How are Mountains Formed

Mountains are a type of landform that are characterized by a higher elevation, in comparison to the surrounding areas. They are higher than 600 meters, and taller and steeper than the hills. The world's tallest mountains are located in Asia and the largest range of mountains is present in the Atlantic ocean. Some of the highest mountain peaks are located in the oceans.

Mountains represent varying climatic conditions based on their height (elevation). For example, in case of a tall mountain, the conditions at the base differ from the top of the mountain. In comparison to the mountain base, the top portion is more cold (presence of snow cover) and there is less oxygen and less protection from the sun's rays. Accordingly, the flora and fauna inhabiting the different zones vary. Forests present on the sides of the mountains are called alpine forests.

It is estimated that half of the world population depends on mountains for water. In fact, the major rivers of the world are fed by mountains. Many mountains have glacial lakes that are formed due to melting of the glaciers. Let's take a look at the formation of mountains.

How are Mountains Formed

Mountains are made up of earth and rock materials. The outermost layer of the Earth or the Earth's crust is composed of six plates. When two plates move or collide each other, vast land areas are uplifted, resulting in the formation of mountains. Depending upon the geological process, as to how the mountains are formed and the mountain characteristics, there are five major types of mountains.

Fold Mountains: Fold mountains are the most common type of mountains. Examples of fold mountains are the Himalayas (Asia), the Alps (Europe). They are formed due to collision of two plates, causing folding of the Earth's crust. The fold that descends on both sides is called anticline; whereas, the fold that ascends from a common low point (on both sides) is called syncline.

Fault-Block Mountains: As the name suggests, fault mountains or fault-block mountains are formed when blocks of rock materials slide along faults in the Earth's crust. There are two types of block mountains, namely the lifted and tilted. In the former type, the mountain has two steep sides; whereas, the tilted type has one steep side and gentle sloping side. Example of fault-block mountain is the Sierra Nevada mountains (North America).

Volcanic Mountains: Volcanic mountains are formed due to volcanic eruptions, for e.g. Mount Fuji (Japan). They are formed when volcanic magma erupts and piles up on the surface of the Earth.

Dome Mountains: Dome mountains are formed when the hot magma rises from the mantle and uplifts the overlying sedimentary layer of the Earth's crust. In the process, the magma is not erupted, but it cools down and forms the core of the mountain. Example of dome mountain is the Navajo Mountain in Utah. They are called dome mountains due to their appearance that resembles dome shape.

Plateau Mountains: Plateau mountains are pseudo mountains that are formed because of erosion. An example of plateau mountain is the Catskill Mountains (New York). They usually occur near the fold mountain ranges.

There are also some mountains that are formed as a result of many forces of the Earth. Though the Rockies in North America is formed due to folding, there are mountains in the same range that are formed by faulting and doming. In nature, there is a continuous process of glaciation, soil erosion, and mechanical and chemical weathering, which altogether play a major role in altering the shape and characteristics of mountains.