Rivers Flashcards
What does an upper course/youthful river look like
☆Small river
☆Flows down steep slopes
☆Erodes river bed vertically
Youthful river feature features
•V-shaped Valley
•Interlocking spurs
•Waterfalls
What does a mature river look like
☆Large river
☆Flows quickly down gentle slopes
☆Erodes laterally
Mature river features
•Meander
•Wide valleys
What does an old age stage river look like
☆Very large river
☆Flows across flat slopes
☆Deposits loads carried upstream
Old age stage river features
Ox bow lakes
Flood plains
Deltas
Levees
How is a waterfall formed?
•River flows over an area where hard rock is ontop of soft rock
•River wears away soft rock,this develops a vertical drop were the soft and hard rock meets(called a waterfall)
•At the base a plunge pool develops due to the hydraulic action of the falling water,and the abrasion of the load swirling around the bottom
•The rock above the plunge pool is undercut + left hanging + eventually falls into the plunge pool. The waterfall erodes upstream
What is a waterfall a feature of?
A waterfall is a feature of erosion found in the youthful stage of a river
What is a meander a feature of?
A meander is a feature if erosion and deposition found in the mature stage of a river
How is a meander formed
•Water flows quickly on the outside of the river bend. It erodes by a mix of hydraulic action and abrasion.
•Water flows slower inside of the river bend. Material is deposited on the inside as the river loses energy
What is an ox-bow lake a feature of
An ox-bow lake is a feature of erosion and deposition found in the old age stage
How is an ox-bow lake formed
•Erosion by hydraulic action + abrasion wears away the outside bank of the meander. The neck of the meander begins to narrow.
•During floods, the water’s energy increases. It takes the shortest course by breaking through the neck + starts flowing in a new more direct course.
•Deposits of aluminum build up and seal off both ends of the meander. The old section of the meander is cut of from the main river
Source
Place where the river begins
Tributary
A stream/river that joins the large river
Flood plain
An area that gets covered with water during floods
