Post on 02-Jan-2016
What landforms and features are associated with the middle course of a river?
LO: To investigate how meanders and ox-bow lakes form.
What is the geographical name for rain, hail, sleet and snow?
–Percolation
–Infiltration
–Precipitation
What is the name for the area of land which is drained by a river?
–Mouth
–Drainage Basin
–Confluence
Learning Outcomes
• Students MUST be able to describe what a meander is and identify the processes which have produced it.
• Students SHOULD be able to explain the formation.• Students COULD suggest how meanders turn into Ox
Bow lakes.
http://www.bbc.co.uk/learningzone/clips/rivers-meanders/403.html
What is a meander?
Meanders are large bends in the course of a river.
They begin to appear as the valley floor becomes flatter and lateral erosion become more significant than vertical erosion.
Water flows fastest.
Water flows slowest.
Deposition takes place.
Lateral erosion (corrasion) takes place.
Sand and shingle builds up to form a slip off slope.
Undercutting takes place and forms a river cliff.
River is deeper.
River is shallower.
Bank will eventually collapse.
Has less friction and therefore more energy.
Most likely to…Inside or outside?
How do Ox-bow lakes form?
The abandoned part of a meander after a river has straightened its course by eroding through the neck of the meander.
I: Water flows fastest.
A: Water flows slowest.
C: Deposition takes place.
J: Lateral erosion (corrasion) takes place.
G: Sand and shingle builds up to form a slip off slope.
H: Undercutting takes place and forms a river cliff.
D: River is deeper.
E: River is shallower. F: Bank will eventually
collapse.
B: Has less friction and therefore more energy.
Most likely to…
Inside or outside?