The Peninsular Plateau of India

The peninsular plateau is India's oldest landmass, a large tableland of ancient crystalline and metamorphic rocks that has been stable for hundreds of millions of years. Unlike the young Himalayas, it has not been folded in recent geological time. Instead, it has been worn down by erosion and broken by faults, so its surface is a mix of rolling uplands, broad valleys and isolated hills. It covers much of central and southern India, rising from the coastal plains towards the interior and sloping gently from west to east, which is why most peninsular rivers flow eastwards into the Bay of Bengal.

The plateau is usually divided into two broad parts. The Central Highlands lie north of the Narmada river and include the Malwa plateau, the Bundelkhand and Baghelkhand uplands, and the Chotanagpur plateau in the east, which is rich in minerals. The Deccan Plateau lies south of the Narmada. It is bounded by the Western Ghats in the west, the Eastern Ghats in the east, and the Satpura range in the north, and it is built largely of volcanic basalt in the north-west, known as the Deccan Traps, and older rocks further south. The contrast matters: the Deccan Traps give rise to black soil, while other parts of the plateau have red and laterite soils.

Two features deserve special attention. First, the plateau is a storehouse of minerals: iron ore, coal, manganese, bauxite and mica are concentrated here, especially in the Chotanagpur region and central India. Mining and industry therefore cluster on the plateau, bringing jobs but also displacement, forest loss and pollution. Second, the plateau's rivers, such as the Godavari, Krishna and Kaveri, are mostly rain-fed and seasonal, unlike the snow-fed Himalayan rivers. Their flow varies sharply between monsoon and dry months, so dams, tanks and groundwater matter greatly for farming and drinking water.

For civil studies, the peninsular plateau is a lesson in old geology with new consequences. Its age explains its mineral wealth and its hard, less fertile soils in places; its slope explains its east-flowing rivers; and its seasonal rainfall explains why water storage and drought management are central to policy in the Deccan. Development here cannot copy the northern plains model, because water, soil and terrain behave differently.