Rajmahal hills
Topic: Structure and Physiography of India: Himalayas, Plains, Peninsula, Coasts and Islands · NCERT: Class 11, Ch 2 "Structure and Physiography"; Class 11, Ch 3 "Drainage System"
Meaning
The Rajmahal hills are hills in Jharkhand at the northeastern edge of the Peninsular plateau. They are made of basalt, a dark rock formed from old lava flows. They are part of the northern edge of the Peninsular Block. When the Himalayas rose, India's northeastward push opened a huge fault (crack) between these hills and the Meghalaya plateau. This sunken zone is the Malda fault, and rivers later filled it with sediment.
Example
At the Rajmahal hills in Jharkhand, the Ganga turns south around the hills before it enters West Bengal and its delta.
Don't confuse with
- Meghalaya plateau: it is a detached piece of the same Peninsular rock, but it lies across the Malda fault in the north-east. The Rajmahal hills are still joined to the main plateau.
Related concepts
- Peninsular Plateau
- Patland plateau
- Chambal ravines
- Central Highlands
- Aravalli Range
- Delhi ridge
- Malwa plateau
- Vindhyan range
- Satpura range
- Maikal range