River Landforms – Upper Course

Upper Course

What are the characteristics of:1.the river and 2.the valley in the Upper Course

1. Lowest volume of water2. A narrow channel with a steep

gradient;3. The river erodes downwards. 4. This vertical erosion results in a

number of distinctive landforms including:• V shaped valley cross section• narrow valley floor• interlocking spurs• river’s load is of various sizes and

angular.

Characteristics of the upper course of a river:

How does a v-shaped valley form?

1. Vertical erosion in the river channel 2. Weathering of the sides of the valley sides 3. Mass movement of materials down the valley sides, 4. Material is gradually transported away by the river.5. As the river flows through the valley it is forced to swing from side to side around more resistant rock outcrops (spurs).6. As there is little energy for lateral erosion, between spurs of higher land creating interlocking spurs

Headward Erosion

1. Vertical erosion (in the form of abrasion, hydraulic action and solution) in the river channel

2. The valley sides are weakened by weathering processes and continued vertical erosion at the base of the slope.

3. Gradually mass movement of materials occurs down the valley sides, gradually creating the distinctive v-shape.

4. This material is then gradually transported away by the river when there is enough energy to do so.

5. As the river flows through the valley it is forced to swing from side to side around more resistant rock outcrops (spurs). As there is little energy, the river continues to cut down vertically flowing between spurs of higher land creating interlocking spurs.

So how does a V-shaped valley form?

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Key Terms

• V-shaped Valley – a valley which resembles a 'v' in cross section. These valleys have steep sloping sides and narrow bottoms.

• Interlocking Spur - spurs are ridges of more resistant rock around which a river is forced to wind as it passes downstream in the upper course. Interlocking spurs form where the river is forced to swing from side to side around these more resistant ridges.

• Load - collective term for the material carried by a river.

Middle Course Features and Processes

Middle Course

What are the characteristics of:1.the river and 2.the valley in the Middle Course

Formation of meanders

Meander Formation

Riffles and

Pools

Formation of Floodplains

• Flat land bordering a river and made up of alluvium (sand, silt, and clay) deposited during floods. When a river overflows, the floodplain is covered with water.