How Are Mountains Formed?

By Joyce Chepkemoi on April 25 2017 in Environment

Mount Everest.
Mount Everest.

How Are Mountains Formed?

Some geological processes like folding, volcanic activity, faulting, metamorphism, etc., can lead to the formation of mountains. Mountains are landforms which rise for over 600 meters than the surrounding land area. Mountains stand as one of the most remarkable geological landforms in the world and often characterize the region in which they are located. The landforms have social, ecological, historical, political, and religious significance depending on the environment. In medieval times, before the advancement of modern geology, some communities regarded mountains as the home of God and subsequently as places to get closer to God. The mountains’ formation takes place over centuries, and geologists have undertaken extensive research in the processes leading to the landforms.

The Process Of Mountain Formation

Mountains are an outcome of the movements of the Earth’s crust, which is the Earth’s outer layer. The Earth’s crust consists of six massive slabs referred to as tectonic plates, which are always moving a few centimeters annually. Two tectonic plates moving against each other cause the thickening and deformation of the crust and land mass is forced upwards to form mountains. Over time, mountains are subjected to erosion from elements such as the wind, ice, and rain, causing their surfaces to be younger than the rocks which initially formed them. Depending on the tectonic forces at work, different types of mountains are formed.

Fold Mountains

This kind of mountain is the world’s most common of the landform. During their formation, two tectonic plates crash into each other at a convergent plate boundary and buckle and fold. This movement can be illustrated by pushing a paper together. This process often leads to the formation of mountains which stretch as far as thousands of kilometers. The Himalayan Mountain Ranges, one of the most spectacular mountain ranges, formed after the Eurasian and Indian Plates collided. The ranges are continuously rising since the plates continue to move towards each other, a process which sometimes triggers earthquakes in the region. The Andes Mountains of South America were similarly formed after the Nazca Plate subducted under the South American Plate, a geological process which is still ongoing. The Andes Mountains stretch across six countries for more than 7,000 km. Other examples of Fold Mountains include the Alps in Europe, the Rockies in North America, and the Urals in Russia. Fold Mountains are often characterized by distinct microclimates, glaciated valleys, and fast-flowing rivers.

Volcanic Mountains

The term volcanic mountains suggest that they are formed by volcanoes. When a tectonic plate subducts beneath another, magma is pushed to the surface. Once on the surface, what is now called lava gradually builds into a mountain. The mountain is made up of lava and piles of rock. A volcanic mountain can either be a shield volcano or a stratovolcano. Stratovolcanoes have steep rising cones since the emitted materials during their formation have higher viscosity and therefore cool fast before spreading far. These volcanoes erupt less but more violently than those of shield volcanoes. A shield volcano is marked by a gently sloping cone since basalt, and other low-viscosity materials are emitted during their formation. The Muna Loa (Hawaii), Nyamuragira (DRC Congo), and Alcedo Volcano (Ecuador) Mountains are examples of shield volcanoes. Examples of stratovolcanoes are Mount Kenya (Kenya), Mount Boucherie (Canada), and Mount Churchill (Alaska). In some cases, magma pushes under the surface of the earth’s crust and causes the overlying rock to rise. The magma eventually cools to form hardened rock leaving an uplifted area referred to as a dome mountain. The mountain is named for its shape resembling the top half of a sphere. Examples of these mountains include the Enchanted Rock and Navajo Mountain in the US.

Block Mountains

Block Mountains or fault-block mountains arise as a result of faults in the crust. The faults enable rocks to move past one another, a process known as rifting. Rocks on one side rise higher in comparison to the others, and they form Block Mountains (horsts) while the other blocks of rocks drop to form depressed regions (graben). The graben can in some cases form rift valley systems. The Block Mountains, on the other hand, break up into chunks which either move up or down or end up getting stacked on one another. The mountains are characterized by a steep front side which is in contrast to the sloping back side. A notable example of Block Mountains is the Sierra Nevada, a block stretching 80 km wide and 650 km long. The East African Rift consists of numerous active volcanoes from Mozambique all the way to Eritrea. Other examples of Block Mountains include the Harz Mountains in Germany and the Grand Tetons in the US.

Plateau Mountains

Plateau Mountains form in proximity to fold mountains, and unlike other mountains, they arise as a result of erosion. Plateaus are large flat regions which have been raised above sea level by forces on the earth. Over time, rivers and streams cut across the plateau causing erosion and forming mountains in the process. Continued erosional processes may erode the mountain entirely over centuries. Examples of these mountains include the Catskill Mountains (US) and the mountains of New Zealand.

Significance Of Mountains

Mountains have numerous benefits as well as far-reaching significance. Mountains in different parts of the world are revered areas for spiritual reasons for instance Mount Ararat, Mount Zion, Mount Olympus, Mount Zion, Mount Kailash, Mount Taranaki, and Mount Meru. These mountains are at the center of particular religions, religious practices, as well as myths and legends. Mountains are home to varieties of flora and fauna, and they are recognized as biological hotspots especially in areas where they remain undisturbed. In different regions of the world, mountains are protected in reserves and parks to protect their biological and ecological diversity.

Other mountains are recognized for their role in history such as the Blue and John Crow Mountains in Jamaica which served as havens for escaped slaves. In other areas, mountains have been integral to the culture of the inhabiting communities. Mountains also promote favorite recreational activities including rock-climbing, hiking, sight-seeing, photography, ice climbing, snowboarding, and mountaineering. Mining, grazing, and logging are some of the economic activities supported by mountains. In recent years, mountains have harbored rebels such as the Nafusa Mountains in Libya. Mountains also affect the climate and weather patterns in different part of the world. The block wind and receive more rainfall compared to other low laying surrounding areas. When air move over the mountain it is forced up the mountain therefore cooling and condenses and fall as rain. The higher the mountain is above the sea level the cooler it becomes at the top.

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