Rivers Flashcards
(77 cards)
Define floodplain
Wide, flat, floor of a river valley over which the river floods during heavy times of rainfall
Where does solution occur?
Solution occurs throughout the river, but especially in areas with limestone rock
Define levee
Natural ridge of material deposited along the banks of a river in its old stage
Which stage do meanders occur in?
Middle course
Where does dendretic drainage occur?
Areas with uniform rock types -> equal erosion
What stage of the river do oxbow lakes occur in?
Old age stage
What fluvial process (/s) is present in the old age stage of the river?
Deposition
Give an Irish example of a flood plain
All rivers in Ireland eg. River Shannon, Co Limerick and Cavan
Define suspension
Fine, light material is carried along by the river
What is the gradient of the river in the mature stage?
Gentler
What stage of the river do floodplains occur in?
Lower course
Draw labelled diagram of watershed
See notes
Explain the formation and erosion of waterfalls (30m)
See notes
What is the gradient of the river in the youthful stage
Steep
Which processes form meanders
Erosion and deposition
Explain the process of solution
Some types of rocks like limestone dissolve in the slightly acidic water of the the river, gradually removing material from riverbed and banks
What is the speed of the river in the youthful stage
Fast
What does trellis drainage look like?
Tributaries join river at right angles
What are lacustrine deltas?
Deltas where rivers flow into lakes
What are some key landforms of the youthful stage of the river?
- V-shaped valleys
- Rapids
- Gorges
- Waterfalls
- Interlocking spurs
What does dendretic drainage look like?
Like tree branches, tributaries flow into the main river channel at right angles
Which processes form a delta
Deposition and erosion
Where does saltation occur?
In the middle course, where the river starts to lose energy but still moves smaller particles
Define traction
Large boulders and rocks are rolled along riverbed