Geography

Concepts to cover

1. Drainage basin, catchment, watershed and divide; classification by size and origin
2. Himalayan versus Peninsular rivers: perennial flow, gorges and meanders, deltas versus estuaries, age
3. Antecedent (Indus, Sutlej, Brahmaputra) and superimposed drainage
4. Evolution: the Indobrahm or Shiwalik river and its dismemberment into Indus, Ganga and Brahmaputra
5. Pleistocene shifts between Indus and Ganga systems: palaeo-Sarasvati, Yamuna and Sutlej capture, river dolphin evidence
6. Evolution of Peninsular drainage: subsidence of the western flank, Narmada and Tapi rift valleys, tilting to the east