Question

ch 2 geography class 9 handwritten notes photo

Answer 1

Answer:

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Introduction :

• India has all major physical features of the Earth, i.e. mountains, plains, deserts, plateaus and islands.
• In India the soil colour varies from place to place as it is formed from different types of rocks.
• India is a large landmass formed during different geological periods.
• India’s relief features are outcome of other processes like weathering, erosion and deposition.
• India has varied physical features whose formation can be explained on the basis of the ‘Theory of Plate Tectonics’.
• According to the theory of Plate Tectonics the seven major and minor plates that form the Earth’s crust keep moving, causing stress and thus leading to folding, faulting and volcanic activity.
• Plates can have convergent, divergent and transform boundaries.
• India’s peninsular part is made from one of the oldest landmass of the world ‘Gondwana land’. It was a single landmass comprising of India, Australia, South Africa, South America and Antarctica.
• The physical features of India can be grouped under the following physiographic divisions :

(i) The Himalayan Mountains.

(ii) The Northern Plains

(iii) The Peninsular Plateau

(iv) The Indian Desert

(v) The Coastal Plains

(vi) The Islands.

The Himalayan Mountains :

• The Himalayas are young-fold mountains which are the loftiest and one of the most rugged mountain barriers of the world.
• The Himalayas are 2400 km long, 400 km to 150 km wide from Kashmir to Arunachal Pradesh respectively.
• The Himalayas have three parallel ranges in the longitudinal extent namely :
• — Great or Inner Himalayas also called Himadri. It is the highest mountain range with average height 6000 m.

• — Middle Himalayas or Himachal. The altitude varies between 3700 and 4500 m. It includes ranges like Pir Panjal, Dhaula Dhar and Mahabharat.

The Northern Plains :

• It is formed by the interplay of the three major river systems – the Indus, the Ganga and the Brahmaputra.
• The Northern Plains spread over an area of 7 lakh sq. km, 240 km long and 240 km to 320 km broad.
• The rivers that flow to the plains from the mountains are involved in depositional work.
• Difference in relief causes the Northern Plain to have four regions.
• — Bhabar — laying at the foot of Shiwaliks, a narrow 8 to 16 km wide belt of pebbles.

• —Terai — lying next to Bhabar, a wet and marshy area with wildlife and forests.

The Indian Desert :

• The undulating sandy plain covered with sand dunes towards the western margins of the Aravalli Hills is the Indian Desert.
• Crescent shaped dunes called barchans cover large parts of the Indian Desert.
• It has a very less rainfall around 150 mm.
• Luni is the only large river in this region.

The Islands :

• The Lakshadweep Islands group in the Arabian Sea is close to Kerala.
• The Lakshadweep Islands were formerly known as Laccadive, Minicoy and Amindive.
• The Andaman and Nicobar Islands are an elongated chain of islands located in the Bay of Bengal.
• The Andaman and Nicobar Islands are an elevated portion of submarine mountains.
• The regions in India complements each other and makes the country richer in its natural resources. Mountains are the source of forests and water. Plains provide grains. Plateaus are storehouses of minerals. Coastal areas support fishing and ports.