On the basis of mode of origin, mountains can be broadly classified into two categories – Original/ Tectonic Mountains and Circum-erosional/ Relict/ Residual Mountains.  A mountain is a landform that rises dramatically above its surroundings, with steep slopes, a small peak area, and significant local relief. This article will explain to you about Classification of Mountains on the Basis of Mode of Origin which will be helpful in Geography preparation for the UPSC Civil Service exam.

What is a Mountain?

• Any natural elevation of the earth's surface is referred to as a mountain.
• The mountains could have a narrow peak and a large base. It is much higher than the surrounding areas. Some mountains tower above the clouds.
• The climate becomes cooler as you ascend.
• Some mountains have ice rivers that are permanently frozen. They are known as glaciers.
• Some mountains are hidden beneath the water and cannot be seen.
• Mountain places have fewer population because of the tough climate.
• Because the hills are steep, there is less ground suitable for agricultural.
• Mountains can be grouped in a straight line known as a range.
• Many mountain systems are composed of hundreds of kilometers of parallel ranges. The Himalayas, Alps, and Andes are Asian, European, and South American mountain ranges, respectively.

Classification of Mountains on the Basis of Mode of Origin

Original/ Tectonic Mountains

• These mountains are formed due to large-scale movements in the tectonic plates and the resulting collision and folding of plates.
• These mountains are further classified into Block mountains, Fold Mountains, Dome Mountains, Mountains of Accumulations and Circum-erosional/ Relict Mountains.

Fold Mountains

• Fold mountains are formed due to large-scale collision of tectonic plates which results in subduction and folding.
• The Himalayas, Rockies, Andes, Balkan Mountains, Jura, and Zagros mountains are some examples.
• The majority of fold mountains are made up of sedimentary and metamorphic rocks that originated under high pressure and at low temperatures.
• When an underlying layer of ductile minerals, such as salt, is present, many fold mountains occur.
• The Himalayas, Andes, and Alps are among the well-known fold mountains.

Block Mountains

• Block Mountains are formed when a fault block is raised or tilted.
• Higher blocks are called horsts and troughs are called grabens
• Examples include the Vindhya Range, Satpura Range, Sierra Nevada Range, Rhila Rhodope mountain range, etc.

Dome Mountains

• These mountains form when a large amount of molten rock (magma) pushes its way up beneath the Earth's crust but doesn't actually erupt onto the surface.
• Over time, the magma cools and solidifies, creating a dome-like structure. Erosion can then expose the dome.
• Examples: The Black Hills in South Dakota, USA, is an example of dome mountains.

Mountains of Accumulations (Volcanic Mountains)

• Volcanic Mountains, also known as Mountains of Accumulations, are generated by the buildup of volcanic debris.
• The volcanic debris is thrown out and then lands in a mountain-like shape surrounding the crater.
• If the lava is thin and basic in composition, it spreads across a large area, generating a flatter cone with a lower elevation and a softer slope.
• A small volcanic cone sharply sticking out is the consequence of its thick and acidic composition.
• Lava, ash, and cinders are sometimes flung out with the lava. Ash and cinder cones are two types of volcanic cones.
• Examples: Mount Mauna Loa in Hawaii Island, Mount Popa in Myanmar, FujiYama in Japan.

Circum-erosional/ Relict/ Residual Mountains

• These are the remains of historic fold mountains that have been exposed due to denudation (strip of covering).
• Residual mountains can also form from plateaus that have been carved into hills and valleys by rivers.
• Hills such as the Nilgiri, Palkonda, Parasnath, and Rajmahal, as well as mountains such as the Aravalli, Vindhya, and Satpura, are examples of relict mountains in India.

Significance of Mountains

• Mountains are particularly valuable for their biodiversity, clean water, research, cultural variety, recreation, landscape, and spiritual benefits.
• Mountains have an important role in supplying renewable energy to downstream cities and remote mountain communities, particularly through hydropower, solar electricity, wind power, and biogas.
• Mountains are known as natural "water towers" because they serve as crucial headwaters for many rivers and other sources of freshwater.
• This freshwater comes from melting snow, which creates streamflow that eventually ends up in streams, rivers, lakes, and seas. This meltwater can also be used to rehydrate aquifers.
• They help in preventing the speed of wind.
• Air and clouds in the air are pushed up the mountain slopes by the wind.
• Warm, moist air masses moving up and over a mountain swell as the air pressure holding them in expands.
• Mountain destinations draw tourists for a variety of reasons, including the climate, clean air, unique landscapes and fauna, visual beauty, local culture, history, and heritage.

Conclusion

Origin-based classification categorizes mountains based on the geological processes that formed them. Mountains are formed due to the large-scale movements of the earth's crust and the collision of the tectonic plates. Mountains are thus created by the tectonic flow of mountains that make the rock layers fold and overlap. In addition, the lithospheric plates continuously move and whenever they bump into each other, they form mountain chains.

FAQs 

Q1: What are the main classifications of mountains based on their origin?

Q2: What are fold mountains, and how do they form?

Q3: Can you explain the characteristics of fault-block mountains?

Q4: What are volcanic mountains, and how do they differ from other mountain types?

Q5: How do mountain classifications impact the environment and human activities?

MCQs 

1. Which type of mountain is formed by the folding of the Earth's crust?

A) Fault-block Mountains

B) Volcanic Mountains

C) Fold Mountains

D) Plateau Mountains

2. What is the primary process involved in the formation of fault-block mountains?

A) Faulting

B) Erosion

C) Weathering

D) Sedimentation

3. Which of the following is an example of a volcanic mountain?

A) Himalayas

B) Rockies

C) Mount St. Helens

D) Appalachian Mountains

4. What distinguishes volcanic mountains from fold and fault-block mountains?

A) Their height

B) Their origin

C) Their location

D) Their shape

5. Which mountain range is an example of fold mountains?

A) The Himalayas

B) The Andes

C) The Sierra Nevada

D) The Ural Mountains

GS Mains Questions and Model Answers

Q1: Discuss the different types of mountains based on their origin and their significance in geography.

Answer: Mountains can be classified into three primary types based on their origin: fold mountains, fault-block mountains, and volcanic mountains. Fold mountains are formed by the folding of the Earth's crust due to tectonic plate collisions, creating significant geological structures such as the Himalayas. These mountains often possess rich mineral resources and play a crucial role in influencing climate patterns in surrounding areas.
Fault-block mountains are formed through faulting processes where blocks of the Earth's crust are uplifted or tilted, resulting in rugged terrains like the Sierra Nevada. These mountains can serve as natural barriers, affecting human settlement and transportation routes. Volcanic mountains, on the other hand, arise from volcanic activity, characterized by the eruption of magma that solidifies into rock. Examples include Mount St. Helens and Mount Fuji. These mountains are vital for understanding geological processes and can impact land fertility through volcanic soil. Each type of mountain contributes uniquely to the environment, biodiversity, and human activities, highlighting their significance in geographical studies.

Q2: Analyze the impact of mountains on human activities and environmental conditions.

Answer: Mountains significantly impact human activities and environmental conditions, influencing aspects such as climate, agriculture, and settlement patterns. Their elevation creates diverse microclimates, often leading to variations in temperature and precipitation. This can support unique ecosystems, contributing to biodiversity. In terms of human activities, mountains can pose challenges for transportation and communication, often requiring engineering solutions like tunnels and bridges. However, they also provide opportunities for tourism and recreation, with many mountain ranges attracting visitors for hiking, skiing, and spiritual retreats. Economically, mountains can be rich in resources such as minerals, timber, and freshwater, supporting local economies and industries. Agricultural practices may be adapted to suit the terrain, with terracing and agroforestry techniques utilized in mountainous regions. Conversely, the environmental fragility of mountain ecosystems necessitates careful management and conservation efforts, as they are often sensitive to climate change and human encroachment. Understanding the multifaceted relationships between mountains, human activities, and environmental conditions is crucial for sustainable development and conservation efforts.

Q3: Evaluate the role of tectonic activity in the formation and classification of mountains.

Answer: Tectonic activity plays a central role in the formation and classification of mountains, influencing their structure, type, and distribution. The movement of tectonic plates results in various geological processes, including folding, faulting, and volcanic activity, each leading to distinct mountain types. Fold mountains are primarily formed at convergent plate boundaries where tectonic plates collide, causing the Earth's crust to bend and fold. This process not only creates majestic ranges like the Himalayas but also leads to the formation of valuable resources such as minerals and fossil fuels. Fault-block mountains result from tectonic forces that create fractures in the Earth’s crust. As these blocks are uplifted or tilted, they form steep, rugged landscapes like the Sierra Nevada. This classification highlights the importance of faulting as a mechanism in mountain formation.
Volcanic mountains are directly linked to tectonic activity, specifically at divergent or convergent boundaries where magma can rise to the surface. This classification emphasizes the dynamic nature of the Earth’s crust and its ability to create new landforms through volcanic eruptions. Overall, tectonic activity is integral to understanding mountain formation and classification, reflecting the complex interactions between the Earth’s geological processes and the resulting landscapes.

Previous Year Questions on  on the Basis of Mode of Origin

1. UPSC CSE Mains 2020

Question: Analyze the classification of mountains based on their origin and provide examples of each type.

Answer: Mountains can be classified based on their origin into three main categories: fold mountains, fault-block mountains, and volcanic mountains. Fold mountains, formed by the collision of tectonic plates, are exemplified by the Himalayas, which result from the convergence of the Indian and Eurasian plates. Fault-block mountains arise from tectonic forces that cause the Earth's crust to fracture, leading to formations like the Sierra Nevada range in the United States. Volcanic mountains, on the other hand, originate from volcanic activity, with Mount St. Helens in the USA serving as a notable example. Each classification highlights distinct geological processes and contributes to our understanding of Earth's topography and the dynamic nature of its surface.

2. UPSC CSE Mains 2018

Question: Discuss the impact of mountain types on regional climates and ecosystems.

Answer: The type of mountains present in a region significantly influences its climate and ecosystems. Fold mountains, such as the Himalayas, often create barriers that affect weather patterns, leading to increased precipitation on the windward side and dry conditions on the leeward side (rain shadow effect). This results in diverse ecosystems, ranging from lush forests to arid regions.
Fault-block mountains can similarly create microclimates, with their rugged terrain influencing local wind patterns and temperature variations. The steep slopes often support specialized flora and fauna adapted to harsh conditions. Volcanic mountains contribute to soil fertility due to the breakdown of volcanic ash, promoting lush vegetation and biodiversity around their base. Additionally, the geothermal activity associated with these mountains can create unique ecosystems