Indian Physiography basics

Indian Physiography basics

India's physiography (landforms) is commonly divided into six major divisions. UPSC Prelims tests their location, formation and features.

Key points

• The Himalayas (Northern Mountains): young fold mountains formed by the collision of the Indian and Eurasian plates; three parallel ranges — Himadri (Greater), Himachal (Lesser) and Shiwaliks (Outer).
• Northern Plains: formed by alluvium of the Indus, Ganga and Brahmaputra; divided into Bhabar, Terai, Bhangar (old alluvium) and Khadar (new alluvium).
• Peninsular Plateau: oldest landmass, made of ancient crystalline rocks; includes the Central Highlands and the Deccan Plateau.
• Indian Desert (Thar): west of the Aravallis; low rainfall, sand dunes (barchans).
• Coastal Plains: Western coast (narrow; Konkan, Kannad, Malabar) and Eastern coast (wider; deltas of Mahanadi, Godavari, Krishna, Kaveri).
• Islands: Andaman & Nicobar (volcanic/tectonic origin) and Lakshadweep (coral origin).

Example

Q. Which is the oldest physiographic division of India? Answer: The Peninsular Plateau — a part of ancient Gondwanaland.

Tip: Remember "Bhabar → Terai → Bhangar → Khadar" when moving from the foothills towards the rivers.

Analogy

Analogy: India as a big house

Picture India's physiography as one big house:

• The Himalayas are the tall roof and boundary wall in the north — young, high and still rising.
• The Northern Plains are the fertile courtyard garden, made of soil that the rivers keep bringing in.
• The Peninsular Plateau is the old stone foundation — the oldest and hardest part of the house.
• The Thar Desert is the dry store-room on the west side, behind the Aravalli wall.
• The Coastal Plains are the verandahs along the east and west sides — narrow on the west, wide on the east.
• The Islands are garden sheds out at sea — Andaman & Nicobar built of volcanic/tectonic rock, Lakshadweep of coral.

Remember: roof = youngest (Himalayas), foundation = oldest (Plateau).