Deccan Plateau of India
The Deccan Plateau forms the major part of the Peninsular Plateau of India.
The Deccan Plateau of India extends south of the Vindhyan range (which lies in the north) to the tip of Kanyakumari to the south. The plateau region of Maharashtra, Kerala, Karnataka, Tamilnadu and Andhra Pradesh, comprise this Deccan Plateau. This triangular plateau is bounded in the west by the Western Ghat or Sahyadri range and in the east by the Eastern Ghats.
- This region forms a part of the most ancient shield of the world or primeval land.
- It is formed of old igneous rocks of granite, metamorphic rocks like gneiss etc.
- Millions and millions of years of continuous erosion have formed peneplains in many areas.
- The whole plateau slopes from the west to the east, as indicated by the slopes of major rivers Mahanadi, Godavari, Krishna and Kaveri flowing from the west to the east into the Bay of Bengal. But there are exceptions as shown by the rivers Narmada and Tapi flowing from the east to the west into the Arabian Sea, north of the Deccan plateau. Therefore the slope of the plateau is in the opposite direction in this region.
- Compared to the north the southern portion of the plateau gradually rises higher.
- An extensive area to the north-west of the plateau is covered by black coloured basalt. This part is called lava or the Deccan Trap.
Mountain Ranges of the Deccan Plateau
1. Satpura-Mahadev Mountain Ranges: These ranges extend east to west, south of the Narmada River valley, for nearly 900 km. Dhupgarh (1350 meters) is the highest peak of the Satpuras. Located to the east of Satpura-Mahadev ranges is Mahakal range. Amarkantak (1057 meters) is its highest peak. It is important to note that the Satpuras have been formed due to faulting movement of the earth. Thus it is a Block mountain, also called “Horst’. On either side of it due to fault movements rift valleys have formed, called “Graben”, through which river Narmada flows north of the Satpuras, and river Tapti flows through the Graben to the south of the Satpuras.
2. Western Ghats or Sahyadri: Along the western boundary of the Deccan Plateau lays the Western Ghats or Sahyadri mountain range. From the north the Sahyadri or Western Ghats are seen south of the Tapti estuary, extending up to Kanyakumari in the South. Thus it extends like a high wall for 1600 kms. With an average height of nearly 1200 meters. The western slope of this mountain faces the Arabian Sea and raised sharply from the Arabian coast. But to the east it gradually slopes down to the plateau in steps. Kalsubai (1646 meters) is the highest peak of this range. Mahabaleswar (1438 meters) is another important peak. Many large rivers of the Deccan plateau rise from this Western Ghat viz. Godavari, Krishna, Tunga, Bhadra, etc.
3. Ajanta Mountain Range: This range lies to the south of the Satpuras and extends in an east-west direction. It is formed of basalt rocks mainly. Nearly 2000 years ago, caves were cut in the mountainsides in a semi-circle for construction of a Buddhist Vihar. The walls of these cabers have beautiful sculptures and bewitching compositions of paintings, which can be seen even today by some tourists attracted from abroad too.