Streams and RiversDefinitions

Tributary: A stream that runs into another stream or river

River System: A river and all of its tributaries

Watershed: includes all of the land that drains into the river

Floodplain: a nearly flat area along a stream or river that is naturally subject to flooding.

Streams and Rivers ContinuedOxbow: a bow-shaped bend in a river

Oxbow Lake: a bow-shaped lake formed in a former channel of a river.

Delta: a nearly flat plain of alluvial deposit between diverging branches of the mouth of a river, often triangular

Alluvial Deposit: clay, silt or gravel carried by rushing streams and deposited where the stream slows down 

Characteristics of Streams and RiversMeander: to take a winding or indirect course

Velocity: The distance that water travels in a given amount of time.

Gradient: The slope of a stream (vertical distance/horizontal distance)

Characteristics ContinuedDischarge: the volume of water that passes a certain point in a given amount of time

Channel: The path through which the water flows. The size and shape effects the velocity- the more sources of friction the slower the river travels

Streams flow fastest in the middle, just below the surface

The surface is slower because air provides a little friction

The bottom is slower because the ground provides friction

The sides are slower because the edge/shore provides friction

Most youthful river valleys are V-shaped

V-shaped valleys are found in regions where there is enough rain to erode the sides of the valley

Visualizations How Sediment is Transported Meanderings

Erosion occurs on the outside of the bends where the water is moving the fastest

Deposition occurs on the inside of the bends where the water is moving the slowest

Erosion by WindWhen small, loose sediments like sand are available, erosion by wind is possible

Arid regions are the most common places for wind erosion to take place

Ventifacts: wedge-shaped rocks formed by wind erosion, often pitted.

Sand dunes are hills of sand deposited by wind

a.Found wherever there are strong winds and loose sand

b.Have long, gentle slope on windward side

c.Have shorter, steep slope on leeward side