Water Flashcards
Watershed
The highland separating one river basin from another
V-shaped valley
Are usually found in the mountains and hills. They often have very steep sides
Mouth
The end of the river. The mouth may be where the river meets the sea, a lake or a
A large water way. Most rivers flow into the sea and this is where they end their journey
Ox-bow lake
A small arc shaped lake formed when a meander is sealed off by decomposition. Ox-bow lakes are only found on liver flood plains
Meander
A bend in a river
Usually in the middle or lower course
Tributary
A stream or river that flows into and joins a main river
Confluence
Where two rivers or streams meet
Erosion
The degradation and removal of rock material by the river
Abrasion
Degradation of the river bed through the scouring action of materials being being carried by the river
Hydraulic action
Form of mechanical weathering caused by the force of moving water currents rushing into a crack
Attrition
A process of erosion where the collisions between parts of the load lead to them breaking down
Corrosion (solution)
Soluble particles such as carbonates like limestone and chalk are dissolved into the river by weak acids in the water and are then carried away down the river
Transport
The movement of sediment load by water
Load
Any material that is in the river
Traction (bed load)
The rolling of load along the bed of a river channel
Saltation
The transport of load by bouncing along the bed of a river channel
Suspension (suspended load)
The transport of load in the body of water in a river. I.e being carried along in the flow
Solution
Minerals are dissolved from soil or rocks and carried along in the flow
Deposition
When a river loses energy it will drop or deposit some of the material it is carrying
Drainage basin
An area of land drained by a river and its tributaries
What does vertical erosion cause and where and why does it happen?
Happens in rivers in the mountains as they flows down steep slopes.
Vertical erosion causes a v shaped valley
How are interlocking Spurs made?
When the river winds around obstacles of hard rock
When does a waterfall occur?
- river flows over different rock types
- river erodes soft rock faster creating a step
- further hydraulic action and abrasion form a plunge pool beneath
- hard rock above is undercut leaving an unstable top of hard rock
which collapses providing more material for abrasion - process continues - waterfall retreats leaving a steep sided gorge
Precipitation
Moisture falling from clouds as rain, snow or hail
Surface run off
Water flowing over the surface of land into a river
Evaporation
Water lost to the atmosphere as water vapour