Notes On Formation - CBSE Class 9 Geography

India is a land of varied physical features. The physical features of India have evolved over several geological periods. According to the theory of Plate Tectonics the earth’s crust is formed from seven major and some minor plates.

When the plates move, they cause disturbances in the continental crust leading to folding, faulting and volcanic activity. These plates are classified into:

  • Convergent boundary,
  • Divergent boundary and
  • Transform boundary


Convergent boundary is formed when two plates converge or move towards each other. Divergent boundary is formed when two plates move away from each other. Transform boundary is formed when two plates move towards each other, but finally end up sliding past each other.

Peninsular India is a part of an ancient super continent: Gondwanaland.  Gondwanaland originally consisted of a number of landmasses including South America, Africa, Australia, and Antarctica all joined together. Convectional currents split up the crust of Gondwanaland into smaller parts, of which the Indian plate was one.

The Indian plate drifted north till it collided with the Eurasian plate. The collision caused the sedimentary rocks in the Tethys Sea to be lifted upwards. This is how the Himalayas were formed. The oldest physical feature is the Peninsular Plateau. It is composed of igneous and metamorphic rocks, and has hills and wide valleys.

Summary

India is a land of varied physical features. The physical features of India have evolved over several geological periods. According to the theory of Plate Tectonics the earth’s crust is formed from seven major and some minor plates.

When the plates move, they cause disturbances in the continental crust leading to folding, faulting and volcanic activity. These plates are classified into:

  • Convergent boundary,
  • Divergent boundary and
  • Transform boundary


Convergent boundary is formed when two plates converge or move towards each other. Divergent boundary is formed when two plates move away from each other. Transform boundary is formed when two plates move towards each other, but finally end up sliding past each other.

Peninsular India is a part of an ancient super continent: Gondwanaland.  Gondwanaland originally consisted of a number of landmasses including South America, Africa, Australia, and Antarctica all joined together. Convectional currents split up the crust of Gondwanaland into smaller parts, of which the Indian plate was one.

The Indian plate drifted north till it collided with the Eurasian plate. The collision caused the sedimentary rocks in the Tethys Sea to be lifted upwards. This is how the Himalayas were formed. The oldest physical feature is the Peninsular Plateau. It is composed of igneous and metamorphic rocks, and has hills and wide valleys.

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