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Indian Subcontinent and Plate Tectonics

India in the Plate Tectonic Framework

Geological Journey

  • ~150 million years ago – Part of Gondwanaland with Africa, Antarctica, Australia, and South America.

  • ~120 million years ago – Broke away and drifted north across the Tethys Ocean at exceptional speed (~15–20 cm/year).

  • ~50 million years ago – Collided with the Eurasian Plate, closing the Tethys Ocean.

  • Present – Still converging with Eurasia (~5 cm/year), causing active mountain building and earthquakes.

Tectonic Plate of India

  • Indian Plate – Once part of Gondwanaland; now includes the Indian subcontinent and surrounding oceanic crust.

  • Collision with Eurasia – Caused the Himalayan Orogeny and uplift of the Tibetan Plateau.

  • Ongoing Movement – Himalayas rise ~5 mm/year; frequent seismic events occur.

Current Tectonic Setting

  • North – Convergent boundary with Eurasian Plate → Himalayan uplift, seismicity (e.g., Nepal 2015 earthquake).

  • West – Interaction with Arabian Plate along Owen Fracture Zone and Makran Subduction Zone.

  • East – Convergent boundary with Burma and Sunda Plates → Andaman volcanic arc, earthquakes.

  • South – Indian Ocean spreading ridges (divergent boundaries).

Tectonic Zones in and Around India

  1. Himalayan Belt – Active continental collision, high seismic risk.

  2. Indo-Burmese Arc – Oceanic–continental convergence and thrust faulting.

  3. Narmada–Son Lineament – Ancient rift zone with occasional intraplate earthquakes.

  4. Stable Peninsular Shield – Geologically stable but not immune to quakes (e.g., Latur 1993).

  5. Andaman–Nicobar Arc – Oceanic–oceanic subduction zone with active volcanoes (e.g., Barren Island).

Key Geological Terms

  • Orogeny – Mountain-building process.

  • Subduction zone – One plate sinks beneath another.

  • Suture zone – Boundary where two plates have collided (e.g., Indus–Tsangpo Suture).

  • Seismicity – Frequency/intensity of earthquakes.

  • Fold-and-thrust belt – Layers of rock folded and faulted by compression.

  • Craton – Stable continental crust (e.g., Indian Shield).

  • Hotspot volcanism – Volcanic activity from mantle plumes (e.g., Deccan Traps).

Geological & Geopolitical Implications

  • Natural Hazards – Earthquakes, landslides, glacier lake outburst floods (GLOFs), tsunamis.

  • Resource Distribution – River systems and mineral deposits influenced by tectonics.

  • Strategic Geography – Mountain barriers influencing defence, trade, and culture.


Time PeriodEventImpact
~150 MaIndia part of GondwanalandConnected to Antarctica, Africa, Australia
~120 MaBroke away from GondwanalandNorthward drift across Tethys
~50 MaCollision with EurasiaFormation of Himalayas, Tibetan Plateau
PresentActive convergenceEarthquakes, mountain building, volcanism


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