CORE Relief Families And Process Logic
Mountains, plateaus, plains and deserts are four relief families, but they are not four isolated lists. A mountain usually marks uplift along a plate boundary or an old weakened belt; a plateau is a broad elevated surface with steep margins or deep dissection; a plain is a low-gradient surface built by deposition or long erosion; a desert is defined by aridity, not by sand alone. NCERT landform treatment keeps this process link clear: endogenic forces raise or break crust, while rivers, wind, ice and weathering reshape the surface. Rajasthan gives the local cross-check. The Aravalli range is an old resistant belt, the Hadoti-Malwa edge behaves like a dissected plateau margin, the Luni basin shows inland drainage, and the Thar turns aridity into dunes, interdunal plains and salt depressions. This chapter therefore uses world examples to classify forms, then pulls them back to Rajasthan. A RAS map question may ask a desert-continent pair, a peak-country pair, or a plain-crop pair; the same answer depends on knowing the process first. For example, a rain-shadow desert behind a coastal range is not the same as an interior cold desert behind a high plateau. A volcanic plateau with black soil is not the same as an alluvial plain with new river sediment. Relief also controls human use. Mountain belts carry passes, snow-fed drainage, forest zones and hazards; plateaus carry mineral belts, lava soils, tablelands and waterfalls; plains carry dense agriculture and transport; deserts carry pastoralism, salt, wind energy, drought adaptation and scattered oasis or canal settlement. In Rajasthan this sequence is visible from the Aravalli watershed to the Chambal-Hadoti plateau, from Banas alluvium to the Thar dune field. Slope, drainage, rock type and climate must therefore be read together for reliable map reasoning and accurate comparison. Once the process is fixed, names such as Sahara, Gobi, Deccan, Great Plains and Aravalli stop floating as loose atlas labels.