Formation of the Aravalli

 

Formation of the Aravalli Hills (

The Aravalli Hills are among the oldest fold mountain ranges in the world. Their formation dates back to the Precambrian era, roughly 1.5–2.5 billion years ago.

1. Ancient Geological Activity

• The Aravalli range was formed due to tectonic plate movements in very ancient times.

• Two crustal blocks—the Bundelkhand craton and the Marwar craton—collided.

• This collision caused folding, faulting, and uplift of rocks, creating the early Aravalli mountains.

2. The Aravalli Orogeny

• The mountain-building process is known as the Aravalli Orogeny.

• During this event:

  • Sediments in an ancient sea were compressed and folded.

  • These sediments transformed into metamorphic rocks like schist, gneiss, and quartzite.

3. Erosion Over Billions of Years

• After their formation, the Aravalli mountains were continuously eroded by wind, water, and weathering.

• Because of this long erosion:

  • The range is now low and discontinuous compared with younger mountains like the Himalayas.

4. Present Structure

• The range extends about 700–800 km from Delhi through Rajasthan to Gujarat.

• The highest peak is Guru Shikhar in Mount Abu.

✅ In short:
The Aravalli Hills were formed by ancient tectonic collisions and folding during the Precambrian era, followed by billions of years of erosion, which reduced them to the worn-down hills seen today.

If you want, I can also explain:

• Aravalli Hills formation in 5 easy points for exams, or

• A labeled diagram of Aravalli formation (very useful for geography answers).