The Deccan Plateau is the vast elevated tableland that constitutes the core of peninsular India, geologically the most stable and ancient part of the Indian landmass, forming part of the Archaean Gondwana shield. Triangular in shape, it is bounded on the west by the Western Ghats (Sahyadri), on the east by the discontinuous Eastern Ghats, and on the north by the Satpura and Vindhya ranges with the Narmada–Tapi rift valleys marking its northern edge. The name derives from the Sanskrit dakṣiṇa ('south'). Its northwestern portion is the Deccan Trap, a massive flood-basalt province formed by volcanic eruptions associated with the Réunion hotspot near the Cretaceous–Paleogene boundary (~66 million years ago), one of the largest such provinces on Earth. The southern and eastern portions are composed of much older granitic and gneissic crystalline rocks of the peninsular shield.
Physiographically the plateau is divided into several sub-units: the Maharashtra (Deccan Trap) Plateau with its characteristic step-like, terraced hills and black regur soils; the Karnataka (Mysore) Plateau; the Telangana Plateau drained by the Godavari and Krishna; and the Chhotanagpur Plateau in the northeast, a mineral storehouse. The plateau slopes gently eastward, so its major rivers — the Godavari, Krishna, Kaveri (Cauvery), Tungabhadra and Bhima — rise in the Western Ghats and flow east into the Bay of Bengal, except the west-flowing Narmada and Tapi which occupy fault troughs and drain into the Arabian Sea. The black cotton soil (regur) derived from basalt weathering is moisture-retentive and ideal for cotton cultivation, while the eastern crystalline tracts hold India's principal reserves of iron ore, manganese, coal, mica and bauxite, concentrated in the Chhotanagpur and the Chhattisgarh–Odisha belt.
The Deccan has been central to Indian history and economy. It hosted the Satavahana, Chalukya, Rashtrakuta, Vijayanagara and Bahmani polities, and the term 'Deccan Sultanates' refers to Ahmadnagar, Bijapur, Golconda and others contested by the Mughals under Aurangzeb. In contemporary India (2026) the plateau is the seat of the Deccan Plateau's agro-economy — cotton, jowar, pulses and oilseeds in the dry rain-shadow interior — and of major industrial and IT hubs at Bengaluru, Hyderabad and Pune. The interior lies in the rain shadow of the Western Ghats, producing semi-arid conditions and recurrent drought-prone tracts in Marathwada, Rayalaseema and northern Karnataka. The Deccan also yields the famous Golconda diamonds, including the Koh-i-Noor.
For UPSC and allied examinations, the Deccan Plateau is a high-frequency topic in the Geography optional and General Studies Paper I (Indian and World Geography). Prelims questions typically test the distinction between Trap (basaltic) and shield (crystalline) regions, the boundary ranges and rift valleys, river drainage direction, regur soil distribution and mineral belts. Mains and optional answers demand analysis of the Deccan Trap's volcanic origin and its link to the K–Pg extinction, the rain-shadow effect on agriculture, and the correlation between geology, soils, minerals and industrial location. Candidates should also connect the plateau to inter-state water disputes such as the Cauvery and Krishna tribunals.
Example
In 2018 the Supreme Court of India delivered its final verdict on the Cauvery water-sharing dispute between Karnataka and Tamil Nadu, a conflict rooted in the eastward drainage of Deccan Plateau rivers from the Western Ghats.
Frequently asked questions
The Deccan Trap is a flood-basalt province formed by massive volcanic eruptions linked to the Réunion hotspot around 66 million years ago, near the Cretaceous–Paleogene boundary. Its eruptions are theorised to have contributed to the dinosaur extinction, and weathering of its basalt produces the fertile black regur soil.