Streams

Major US Rivers

A drainage basin a.k.a. watershed is

the area of land that drains to a particular lake, wetland or ocean.

DRAINAGE BASIN/Watershed

Where do rivers and streams get their water from? 3 sources

From its source to the SeaA stream begins at its headwaters, often in areas where there is constant runoff of rain or melting snow or an underground spring.The stream continues to flow and combines with other streams (called tributaries) until they become a river systemThe river will flow until its mouth (the end of the river) opens into the ocean, lake or seaThe mouth of a river creates a Delta (a layer of sediment)

TRIBUTARIES, DIVIDES

ALLUVIAL FAN

What is a Stream Erosion?What is a Stream Erosion?

Stream erosion is Stream erosion is the transportation the transportation of weathered of weathered material collected material collected in the stream in the stream

Parts of a River Channel

Bank (outside of a river)

Bar (inside of a river)

Bed (bottom of a river)

RIVER BED

STREAM LOAD

Suspended load

Dissolved Load

YouthfulSteep gradient

Rapids and waterfalls

Stream course is straight

No or very little drainage basin (the area of land that surrounds and include the major river and all of its tributaries.

Youthful

http://www.youtube.com/watch?v=7c3YadMA0_k

http://www.youtube.com/watch?v=so385dCUoJM

http://www.youtube.com/watch?v=NVxVfR5Ll58

HYDROELECTRIC POWER

MatureWeathering and erosional effects have made the land wider and flatter

Speed of river is reduced

Starting to get curvy (meanders)

Drainage basin are forming and more tributaries are joining

MEANDER

Meander – a curve or bend in the river

OldExtreme meanders are present

Land around it is very flat

Speed is super slow

Large drainage basin

Oxbow lakes

Fig. 10.06

Old

MEANDERS/OXBOW LAKE

http://www.school-portal.co.uk/GroupDownloadFile.asp?file=21606

Oxbow Lakes

OXBOW LAKES

EROSION/DEPOSITION

Rejuvenated River

NAME THE STAGE

NAME THE STAGE

NAME THE STAGE

FLOOD PLAIN

http://www.school-portal.co.uk/GroupDownloadFile.asp?file=21394

WATERFALL FORMATION

http://www.school-portal.co.uk/GroupDownloadFile.asp?file=21604

Summary QuestionA Changing River

200 years ago a stream was set as a boundary on some land. Now surveys show that this river is no longer used as an accurate boundary. Why?