Rivers - Glossary

Key Words

Definitions

Alluvium

Material deposited by a river (sand-silt & mud)

Attrition

A process of erosion whereby the load rubs against itself

Channel

What a river flows in

Confluence

Where two rivers meet

Corrasion

Where the load of a river is used to erode the banks and bed

Corrosion

A process of erosion caused by solution ie salt and limestone

Delta

An area of deposition found at the mouth of the river - triangular in shape

Discharge

The amount of water flowing in a river per second

Distributaries

Small channels found on Deltas as the main river splits up

Drainage Basin

The area of land drained by a single river

Estuary

A drowned river valley

Flood Hydrograph

A graph showing how a river responds to different amounts of rainfall

Gorge

A narrow steep sided valley caused by a waterfall

Hydraulic power

A process of river erosion caused by the force of the water

Hydrological Cycle

The cycle of water between the air land and sea

Lag time

The time between the peak rainfall and peak discharge

Meander

A bend in the river - usually in the middle or lower course

Mouth

Where a river enters the sea or a lake

Ox bow lake

A lake formed when a meander is sealed off by deposition

Saltation

Particles bouncing down a river bed

Source

The starting point of a river

Traction

Boulders rolling along the river bed

Tributaries

Small rivers or streams which flow into a larger river

V-shaped valley

Shape of a river in the upper course with steep sides and narrow base

Velocity

The speed of a river's flow

Watershed

High ground that surrounds a drainage basin