Interlocking Spurs, Upper Course:-
the river cuts its deep V-shaped valley in its upper course, it follows the path of the easies trock to erode. Thus it tends to wind its way along, leaving the more resistant areas of rock as interlocking spurs.
V Shaped Valleys, Upper Course:-
In the upper course ofthe river, it cuts rapidly downwards, as the river puts almost all of its energy towards cutting down to base level. This causes the most distinctive river feature, the V-shaped valley. Rocks and other material are washed into the river from the steep valley sides during times of heavy rainfall, adding to the material being carried by the river.
Waterfalls, Upper Course:-
They primarily occur in the upper course of the river. Often a waterfall will form where a band of harder rock lies over a softer one. As the river flows over the edge of the harder, more resistant rock, into its plunge pool, it erodes away the softer rock below, creating an overhang. Once the overhang is big enough the whole thing collapses due to gravity and its own weight. The whole process then occurs again. This means that over time waterfalls will move backwards up the valley, leaving a steep sided gorge in front of them.
Gorges, Upper Course:-
A narrow, very deep canyon with preciptous rocky sides usually carved by a river.
A steep sided valley that has almost vertical sides which cuts into the landscape like a narrow channel.