Major Landforms of the Earth: Mountains, Plateaus, and Plains

The surface of the Earth is not flat; it is made up of a variety of natural features called landforms. These landforms - mountains, plateaus, and plains - are formed by powerful forces inside the Earth and by slow processes like wind and water on the surface. Understanding them helps us see why people live and work in different ways in different places.

Mountains: The Earth's Rising Giants

When you look at a mountain, you are seeing the result of immense forces pushing the Earth's crust upward. A mountain is a natural elevation of the Earth's surface, usually with steep sides and a narrow summit. Most mountains rise at least 600 metres above their surroundings, but what matters more is their dramatic shape - a clear peak, steep slopes, and a base.

Mountains are not all alike. Fold mountains are formed when two tectonic plates collide and the layers of rock crumple like a rug pushed from both ends. The Himalayas, the youngest and highest mountain range in the world, are fold mountains. Block mountains form when cracks in the Earth's crust cause large blocks to be pushed up or down; the Black Forest in Germany is a classic example. Volcanic mountains are built from lava and ash that pile up after an eruption, such as Mount Fuji in Japan.

• Mountains are sources of many rivers; glaciers and snow melt feed streams.
• They create natural barriers that affect climate and movement of people.
• They are rich in forests, wildlife, and scenic beauty, attracting tourism.

Plateaus: Flat-Topped Tablelands

A plateau is a raised, flat-topped area of land that drops steeply on at least one side. Think of it as a tableland - a large, level surface standing high above the surrounding land. Plateaus are often called storehouses of minerals because many of them contain valuable rocks and ores.

Plateaus are classified by their location. Intermontane plateaus are surrounded by mountains, like the Plateau of Tibet, the highest plateau in the world. Piedmont plateaus lie at the foot of a mountain range, with mountains on one side and a plain on the other; the Malwa plateau in India is an example. Continental plateaus are large, ancient plateaus far from mountains, such as the Deccan plateau, which is one of the oldest landforms in India.

• Plateaus are often rich in minerals like coal, iron, and gold.
• Waterfalls on plateaus can be used to generate hydroelectric power.
• Lava plateaus, like the Deccan, are formed by volcanic eruptions that spread lava over huge areas.

Plains: The Fertile Lowlands

A plain is a large, flat, and low-lying area of land. Plains are usually formed by rivers that deposit layers of soil and sand over millions of years, or by the wearing down of mountains and plateaus. Because they are flat, they are easy to build on and farm on.

Plains can be structural (formed by uplift of a flat area), erosional (formed by the wearing down of higher land), or depositional (formed by rivers depositing sediment). The Ganga-Brahmaputra plain in India is a great example of a depositional plain; it is made of fertile soil brought down from the Himalayas.

• Plains have fertile soil, which supports agriculture.
• They are densely populated because flat land makes transport and construction easy.
• Rivers on plains provide water for drinking, farming, and industry.

How Landforms Are Formed: Inside and Outside Forces

The Earth's surface is constantly being shaped by two kinds of forces. Internal forces, such as the movement of tectonic plates and volcanic eruptions, push the crust upward to create mountains and plateaus. These forces work slowly over millions of years, but they can also cause sudden events like earthquakes.

External forces work on the surface. Wind, water, and ice wear down high landforms through weathering and erosion, and then deposit the broken material in lower areas. This is how plains are built and how mountains slowly become smaller over time. The same river that cuts a deep valley in the mountains later spreads fertile soil across a plain.

Thus, every landform is a snapshot of a long battle between building forces and wearing-down forces.

Landforms and Human Life: A Two-Way Relationship

Landforms deeply influence where and how people live. Mountains offer timber, fresh water, and tourism, but they also make travel difficult. Plateaus provide minerals and power, but their dry, rocky surfaces are not always good for farming. Plains, with their fertile soil and flat land, support large populations and become centres of agriculture, trade, and industry.

Humans also change landforms. Farmers build terraces on slopes, engineers cut tunnels through mountains, and dams are built on rivers to control floods and generate electricity. These changes can be useful, but they can also harm the environment if done carelessly.

• Mountain regions often develop tourism and adventure sports.
• Plateau regions are important for mining and hydroelectric power.
• Plains are the most suitable for large-scale farming and dense settlement.

Key takeaways

• The three major landforms of the Earth are mountains, plateaus, and plains.
• Mountains are high, steep-sided landforms; the main types are fold, block, and volcanic mountains.
• Plateaus are flat-topped highlands, often rich in minerals; examples include the Tibetan, Malwa, and Deccan plateaus.
• Plains are flat, low-lying areas formed mainly by deposition of sediments; they are ideal for agriculture and settlement.
• Internal forces build landforms, while external forces like weathering, erosion, and deposition wear them down and reshape them.
• Landforms affect human activities, and human activities also modify landforms.

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