Waterfalls can ber formed by 2 ways: faulting or the unequal resistance of rocks. When a river flows across rocks of different resistance, the less resistant rock is eroded more rapidly than the resistant rock. This results in a change in gradient and causes the water to plunge. Over time, a waterfall can develop.

        Formation of waterfall due to the unequal resistance of rocks

_____________________________________________Waterfall formed by faulting

____________________________________________________________Plunge pool

Sometimes a deep pool develops at the bottom of the waterfall. It is formed as the river plunges and hits the bottom at great force. The force of the plunging water, together with the swirling action of rocks at the river bed erodes the underlying less resistant rock to form a plunge pool.