Question – Describe the process of plateau formation? Also, briefly discuss the characteristics of the Deccan Plateau and its economic importance. – 11 November 2021
A plateau is a flat, elevated terrain that rises sharply in at least one direction from its surrounding area. The plateau covers one third of the Earth’s surface. Plateaus are present in every continent and cover one third of the Earth’s landmass. The Deccan plateau is the oldest plateau in India. Valleys are formed when the sharp currents of rivers emerge while cutting the plateau.
The Columbia Plateau, which is between the Cascade and Rocky Mountains in the United States, is formed by the rapid flow of the Columbia River. Some plateaus have eroded so much that small pits have formed in them. Very old and high density stones are found in some plateaus. Iron and coal ores are found in abundance in the plateau surfaces. The plateau terrain is very useful as there are many mines of minerals.
The French plateau, the Massif Central, the Deccan Plateau, the Katanga Plateau of the Congo (copper ore), the Kimberly Plateau of Australia (diamond mines), the Brazilian Plateau, etc. are very good sources of minerals. The stone of East Africa is known for its diamond mines. Manganese, iron and coal mines are found in the Chota Nagpur plateau in India.
Many waterfalls are found in the plateau areas, which fall from a great height, they remain the main center of attraction for the tourists. In India, there is Hundru Falls on the Swarnalekha River in the Chota Nagpur Plateau and the Jog Falls of Karnataka is very famous. Hydroelectric power is produced in such places.
Not much agriculture is seen in plateau areas. But where the lava has dried up to become clay, there is agriculture. The fertile black soil is found in the Maharashtra part of the Deccan plateau, where cotton is grown. The Lus Plateau of China is one of the most fertile plateaus.
Plateau formation is associated with one of the following processes:
- Volcanoes: Volcanic eruptions that form lava plateaus are related to hot spots. For example, the Deccan Traps, which cover the Deccan Plateau in India, appeared 60–65 million years ago, when India was probably in the same hot spot beneath which was the present-day Réunion volcanic island.
- Crustal shortening: It is the process of pushing/breaking of one piece of land by another or folding of layers of rock. Some plateaus, such as the Tibetan Plateau or the Altiplano, are plateaus formed by crustal shortening. The surface of this type of plateau is composed of very flat, broad valleys, surrounded by steep hills and mountains.
- Thermal Diffusion: When the underlying lithosphere warms rapidly over a wide area – such as by the uplift of warm matter from the underlying asthenosphere – the resulting warming and thermal expansion of the upper mantle causes the overlying surface to rise. For example- the high plateaus of East Africa and Ethiopia. In addition, many plateaus are formed when magma inside the Earth comes to the surface to form a massive plateau.
- Plateau formation due to wind and water erosion: Some other plateaus form over time as wind and rain carry away the edges of a raised area.
Features of the Deccan Plateau
- The Deccan Plateau is spread over 8 Indian states. It covers a wide range of habitats covering important parts of Telangana, Maharashtra, Karnataka and Andhra Pradesh. It is situated between two mountain ranges, the Western Ghats and the Eastern Ghats.
- The north-western part of the plateau is made up of igneous rocks, known as the Deccan Trap. These rocks are found throughout Maharashtra and parts of Gujarat and Madhya Pradesh, making it one of the largest volcanic provinces in the world.
The Deccan Plateau and its region are rich in minerals, agriculture and water resources.
- Agriculture: The region is rich in black soil and is favorable for cotton cultivation. Other crops include tobacco, oilseeds and sugarcane. Crops such as coffee, tea, coconut, arecanut, pepper, rubber, cashew, tapioca and cardamom are widely grown in plantations on the Nilgiri Hills and the western slopes of the Western Ghats.
- Mineral Resources: The mineral resources found in the Chota Nagpur region are mica and iron ore and diamond, gold and other metals in the Golconda region. Large deposits of uranium have been discovered in the Bhima basin of Gogi and the Tummalapalle belt in Karnataka.
- Hydro-Power: Its major rivers- Godavari, Krishna and Kaberi flow eastwards from the Western Ghats towards the Bay of Bengal, and thus the region is an important source of hydroelectricity.
- Tourism: Major tourist places like Ajanta and Ellora Caves and other attractions located in this region are contributing to the economy of this belt. Thus plateaus are important landforms that contribute immensely to economic and recreational value.