River processes * Flashcards
1
Q
What is erosion?
A
- the process that wears away the river bed and banks, and breaks up the rocks that are carried by the river
2
Q
What is hydraulic action?
(erosion)
A
- the sheer power of the water smashes against the river banks
- air becomes trapped in the cracks of the river bank and bed
- this causes the rock to break apart
3
Q
What is abrasion?
(erosion)
A
- when pebbles grind along the river bank and bed
4
Q
What is attrition?
(erosion)
A
- when rocks that the river is carrying knock against each other
- they break apart to become smaller and more rounded
5
Q
What is solution?
(erosion)
A
- when the water dissolves certain types of rock, e.g. limestone
6
Q
What is transportation?
A
- the river picks up sediment and carries it downstream in different ways
7
Q
What is traction?
A
- large, heavy pebbles are rolled along the river bed
8
Q
What is saltation?
A
- pebbles are bounced along the river bed
9
Q
What is suspension?
A
- lighter sediment is suspended within the water
10
Q
What is solution?
(transport)
A
- the transport of dissolved chemicals
11
Q
What is deposition?
A
- when the river loses energy, it drops any of the material it has been carrying
12
Q
What factors lead to deposition?
A
- shallow water
- at the end of the rivers journey, at the rivers mouth
- when the volume of water decreases
13
Q
What is a drainage basin?
A
- the area of land around the river that is drained by the river and its tributaries
14
Q
What is watershed?
A
- the area of high land forming the edge of a river basin
15
Q
What is the source?
A
- where a river begins
