Physical Features of India

• Introduction

  • India has diverse physical features
  • Formed through geological processes and plate tectonics
  • Theory of Plate Tectonics explains Earth's crust movement
    • Convergent, Divergent, and Transform boundaries
    • Gondwanaland (Ancient southern landmass including India)

• Major Physiographic Divisions

  • The Himalayan Mountains
  • The Northern Plain
  • The Peninsular Plateau
  • The Indian Desert
  • The Coastal Plains
  • The Islands

• The Himalayan Mountains

  • Young fold mountains running along northern border
  • Stretches from Indus to Brahmaputra (2,400 km)
  • Width: 400 km in Kashmir to 150 km in Arunachal Pradesh
  • Parallel Ranges
    • Greater Himalayas (Himadri): Highest peaks, core of granite (e.g., Mount Everest, Kanchenjunga)
    • Lesser Himalayas (Himachal): Rugged ranges, famous hill stations (e.g., Kashmir, Kangra, Kullu valleys)
    • Shiwaliks: Outermost range, composed of unconsolidated sediments (valleys called Duns like Dehra Dun)
  • Regional Divisions (from West to East)
    • Punjab Himalayas (Indus - Satluj)
    • Kumaon Himalayas (Satluj - Kali)
    • Nepal Himalayas (Kali - Teesta)
    • Assam Himalayas (Teesta - Dihang)
  • Purvachal (Eastern Hills): Beyond Dihang gorge (Patkai, Naga, Manipur, Mizo hills)

• The Northern Plain

  • Formed by interplay of three major river systems: Indus, Ganga, and Brahmaputra
  • Highly fertile alluvial soil, densely populated
  • Sections
    • Punjab Plains: Western part, dominated by doabs
    • Ganga Plain: Between Ghaggar and Teesta rivers
    • Brahmaputra Plain: Eastern part, mainly in Assam
  • Relief Features
    • Bhabar: Pebble belt parallel to Shiwaliks where rivers sink
    • Terai: Wet, swampy, marshy region south of Bhabar
    • Bhangar: Older alluvium, forms terrace-like features (kankar)
    • Khadar: Newer, younger alluvium of floodplains (very fertile)

• The Peninsular Plateau

  • Tableland composed of old crystalline, igneous, and metamorphic rocks
  • Formed due to breaking and drifting of Gondwanaland
  • Two Main Divisions
    • Central Highlands: North of Narmada river, Malwa plateau, Vindhyas
    • Deccan Plateau: Triangular landmass south of Narmada river
      • Western Ghats (continuous, higher) & Eastern Ghats (discontinuous, irregular)
      • Highest peak: Anamudi (Western Ghats)
  • Rich in minerals (coal, iron ore)

• The Indian Desert

  • Lies towards western margins of the Aravali Hills
  • Undulating sandy plain covered with sand dunes
  • Low rainfall (below 150 mm per year)
  • Arid climate with low vegetation
  • Luni is the only large river in this region

• The Coastal Plains

  • Narrow coastal strips flanking the Peninsular plateau
  • Western Coastal Plain
    • Wedged between Western Ghats and Arabian Sea
    • Three sections: Konkan (North), Kannad (Central), Malabar coast (South)
  • Eastern Coastal Plain
    • Lies between Eastern Ghats and Bay of Bengal
    • Wider and level
    • Two sections: Northern Circar and Coromandel Coast
    • Deltas of rivers like Mahanadi, Godavari, Kaveri

• The Islands

  • Lakshadweep Islands
    • Located near Malabar coast of Kerala
    • Made of coral deposits (Atolls)
    • Earlier known as Laccadive, Minicoy, and Amindivi
  • Andaman and Nicobar Islands
    • Chain of islands in Bay of Bengal extending north to south
    • Bigger in size, more numerous, and scattered
    • Divided into Andaman (North) and Nicobar (South)
    • Strategic importance, high biodiversity, India's only active volcano (Barren Island)