F.5 GCE Geography - Unit 1.3d - #Consolidation Quiz

Label the different landforms visible in the image.

a

b

c

d

interlocking spurs

plunge pools

rapids

waterfalls

Meander scar

River cliff

Point bar

Oxbow lake

Which of the following flows can commonly be seen in meanders with slip-off slopes and river cliffs?

• Laminar

• Helicoidal

• Turbulent

What do we call the fastest flow of water in meanders?

Label the diagram with correct terms.

a

b

c

Inner meanders

Vertical erosion

Outer bank

Inner bank

Outer meanders

Thalweg

Reorder the following statement to explain the formation of meanders.

• Water flowing over alternating pools and riffles flows in a helicoidal pattern.

• This causes the thalweg to move from side to side, eventually creating a sinuous channel.

• The velocity and energy of the river are higher on the outside bend which causes erosion (hydraulic action, abrasion, and corrosion), forming a river cliff.

  The velocity and energy of the river are lower on the inside bends, and causes deposition, forming a point bar.

• The meander is now asymmetrical – deeper on the outside of the bend and shallower on the inside.

Reorder the following statement to explain the formation of oxbow lakes.

• 1. The meandering channel becomes more sinuous because of lateral erosion.

• 1. The meander necks become closer together.

• 1. During a flood the meander necks may be cut off.

• 1. The river then cuts a new, straight, course.

• 1. The old channel will be sealed, leaving the meander behind as an oxbow lake.

Which of the following descriptions related to the outer banks of meanders are correct?

• Lateral erosion can be found there.

• Hydraulic action and abrasion can be found.

• Deposition can be found there.

• The river velocity is the highest there.

• When two outer banks get closer to each other, an oxbow lake may be formed.