Geography - River Landforms

Upper course landforms

The Upper Course is mainly on highland and its landforms are influenced by the dominanace of vertical erosion and the lack of lateral erosion.

Waterfalls, rapids and gorges

• The river channel in the upper course is made of both hard rock (not eroded) and soft rock (eroded much quicker).
• These differences in rates of erosion create steps forming rapids as water flows over them.
• These steps get bigger and form a waterfall.
• On the cross section of a waterfall the hard rock is over the soft rock. The soft rock is eroded fastest due to the splashback of water, creating an overhang of hard rock with no support and a plunge pool beneath.
• This causes the overhang to eventually collapse and the gradual retreat of the waterfall upstream.
• This retreat also causes gorges to form where the waterfall originally was.

V-shaped valleys and interlocking spurs

• In the upper course, vertical erosion is dominant over lateral erosion deepening the valley and thus making them v-shaped.
• Due to a lack of lateral erosion, the river doesn't have enough energy to erode the banks so it has to wind its way through the mountains causing…