Characteristics of rivers

Question 1

Describe upland valley

Answer 1

V shape 
Steeper sides/steep long profiles 
Vertical erosion 
Narrow/non-existent valley floor 
Rapids, waterfalls, lakes.

Question 2

Describe lowland valley

Answer 2

U shape
Gentle long + cross profile 
Wider 
Lateral erosion 
Deposition 
Flood plain

Question 3

Formation of waterfalls and gorges (Upper course)

Answer 3

river flows over more resistant rock, less resistant rock beneath

Rapid erosion of less resistant rock
More resistant rock not worn away as rapidly

force of the water erodes bottom of waterfall –> plunge pool

Eddy currents undercut hard rock, soft rock eroded

Collapse of overhanging hard rock

Waterfall retreats (to form gorge)

Gorge: deep, steep-sided valley

Question 4

Formation of oxbow lakes and meanders (middle + lower course)

Answer 4

Outer bend eroded, faster flowing water, river cliff formed

Deposition, inside bends, water low velocity, slip off slope

Meander increases in size, narrow neck forms

Neck cut, water direct route, flood

Cut-off loop forms oxbow lake

Question 5

Formation of floodplain and levée (lower + middle courses)

Answer 5

Flood occurs
Deposit material

Floodplain:
Meander cut their way through by lateral erosion
Fine material deposited on wide, flatter valley floor surrounding the river

Levée: Large, coarse sediment deposited next to the channel

Question 6

Fourmation of a delta (lower + middle courses)

Answer 6

River meets still water from lake or sea and loses velocity
Deposition builds up
Delta gradually built out into the sea

Question 7

Potholes (upper courses)

Answer 7

River flows over solid rocks

Eddie currents swirl stones around –> corrasion/abrasion

Hollows deeper + wider
Join together

Question 8

Features upper course of river

Answer 8

Potholes
Interlocking spurs
Waterfalls
Gorges

Question 9

Interlocking spurs (upper course)

Answer 9

Vertical erosion, travelling down hill

Winds + bends to avoid areas of hard rock

(spurs of land either side valley)