U.k Geology 4.6

Question 1

How do river landscapes differ between upper, middle and lower courses?

Answer 1

Discharge- increases, tributaries, width
Width- increase, abrasion, tributaries
Depth- increase, abrasion, tributaries
Velocity- increase, steeper gradient, hydraulic abrasion
Sediment load volume- increase, more erosion that bring sediment
Sediment particle size- decrease, rocks break each other
Channel bed roughness- decrease, sediment slowly erodes the smaller sediment
Slope angle- decrease

Question 2

How do oxbow lakes form?

Answer 2

The meander is curved to start. The quicker stream being on the outside slowly erodes the curve to make it straight. Sediment then closes the river to form a curve called an oxbow lake. Grass then grows over the lake causing a meander scar.

Question 3

What is a meander?

Answer 3

A meander is a river the has a lot of bends the curve it around interlocking spurs. The faster and stronger stream is on the outside so the sediment gathers of the other side of the stream while the river cuts a straight river cliff.

Question 4

How do interlocking spurs form?

Answer 4

Weathering occurs on the corners of the valley cliff then it slowly cracks and falls into the stream. This happens until there is slope that can use gravity to pull any more sediment down. This happens over and over again to form interlocking spurs.

Question 5

What are floodplains?

Answer 5

Floodplains are a flat wide piece of land that has low slopes meaning that they store water when it floods.