Stream Erosion and Deposition Grand Canyon, AZ Earth Science Mr. Cloud

The Evolution of a Stream Mr. Cloud: Age 15 Runoff Rills/Gullies  Streams  Rivers

Streams Running water erosion confined to a channel Tributary: a smaller stream that flows into a larger stream i.e. the west branch of the Delaware river (Catskills, NY)

Watershed: an area of land drained by any one stream i. e Watershed: an area of land drained by any one stream i.e. the Mississippi watershed Divide: line/boundary separating watersheds i.e. The Great Divide

Three Factors that Affect Stream Velocity 1. Gradient: slope of the stream as the slope of the land increases, stream velocity increases 2. Discharge: volume of water in a stream as discharge increases, stream velocity increases 3. Stream Channel Shape: shape of the bedrock or loose materials that confine the stream

How do streams carry sediment?

What occurs to the sediment load when velocity changes? When stream velocity increases, sediment load and size increase When stream velocity decreases, sediment load and size decreases. ESRT pg. 6

V-Shaped Valleys

How does water velocity change within a river? **Meandering Stream: curving stream occurs when gradient decreases occurs when velocity decreases - “Old” Stream/River

What occurs to stream velocity when a stream meanders?

Formation of an Oxbow Lake

Formation of an Oxbow Lake

Formation of an Oxbow Lake erosion accelerates on the outside of the meander meander loops form and converge meander is cut off, water takes path of least resistance, and an oxbow lake forms

What occurs to a stream in times of flood? Mississippi Flood Plain (shuttle color-enhanced image)

Natural Levees Levee: is a natural or artificial slope or wall to regulate water levels. It is usually earthen and often parallel to the course of a river or the coast.

How the Levees Failed: Hurricane Katrina

Mississippi River (normal) Mississippi River at Flood Stage

Mississippi flooding in Missouri Bracing for Flood: Clarksville, MO Mississippi flooding in Missouri

What occurs to a stream when it reaches a large body of water? Delta: very end of a stream or river (mouth) Mississippi Delta

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