1. Fluvial Morphology: Landforms Made by Running Water

2. RUNNING WATER  Rivers and Streams
What is the most important geomorphic agent shaping the physical landscape?
RUNNING WATER  Rivers and Streams
What is the work of rivers and streams?
Erosion
Transportation
Deposition
Fluvial Morphology: Study of Landforms Made by Running Water
FLUVIAL: from the Latin fluvins for ‘running water’ or streamflow

4. SOURCES OF WORLD’S WATER
Source % of Supply
Oceans
Ice Sheets and Glaciers
Ground Water
Lakes (Fresh)
Inland Seas / Salt Water Lakes
Soil Moisture
Atmosphere
Rivers*  
* Running water or streamflow is the most significant agent sculpting the Earth’s land surface

5. Sources of stream flow
% of total precipitation runs off as storm flow, and becomes stream flow
The rest of stream flow comes from groundwater discharge, as base flow

6. River Quiz: Amazon: http://www.youtube.com/watch?v=ta35C488dnE
Amazon:

9. Stream Order, Drainage Basin, Watershed and Drainage Divide
Rills  Gullies  Streams 
Stream Order,
Drainage Basin,
Watershed
and
Drainage Divide

10. Mississippi-Missouri Drainage Basin
Lake Itasca is a small glacial lake, approximately 1.8 square miles in area, in the Lake District of Northwestern Minnesota. It is the source of the Mississippi River.

11. Southern California
Watersheds

12. 3-D Drainage System and Stream Model
Fig. 17-3, p. 472

13. Drainage Patterns and Topography

14. The Long Profile of Streams
At their headwaters, the grade of a stream is usually steep
At mid-course, the grade becomes more gently sloping
Near the mouth of the stream, the grade becomes almost flat

15. Stream Gradients
Fig , p. 480

16. Stream Stages
Streams also show three stages of gradation from the mountains to the sea, with associated erosional and depositional features:
Youth
Maturity
Old Age

17. Stream Stage 1 – Youth Characteristics of Youthful Streams
Steep, irregular profile
Headward erosion 
Waterfalls, rapids, and plunge pools
River is deepening its channel
Cutting into bedrock – Vertical erosion*
V-shaped cross-section 
*Reflects the propensity of streams to try and reach their
ultimate base levels (i.e., sea level) or secondary base levels

18. V-shaped Valleys

19. Waterfalls

20. Stream Stage 2 – Mature Valley
Characteristics of Mature Valley Streams
Valley widening begins
Meandering stream  lateral erosion + deposition
Braided channel  deposition (sand bars)
Floodplains

21. Meandering
Streams

22. Meandering Stream
Fig a, p. 489

23. Braided Stream Channel of the Brahmaputra River in Tibet

24. Tectonic Uplift, Stream Rejuvenation and Alluvial Terraces
Downcutting,
and
the Grand Canyon

25. Stream Stage 3 - Old Age Characteristics of Old Age Streams
Wide Alluvial Valley Stage
The channel is quite large and U-shaped
Stream discharge at a maximum and sediment load composed of finer materials
Natural Levees, parallel to the stream channel
on both banks
Other depositional features, including Delta

26. Floodplain Features
Fig , p. 491

27. Mississippi Floodplain

28.  Delta
Large deposit of alluvial sediment located at the mouth or estuary of a stream where it enters a body of standing water, usually a ocean or a lake.
Deltas are created when the
sediment load carried by a
stream is deposited because
of a sudden reduction in
stream velocity.
Delta surface is characterized by distributaries
Some deltas, like that of the Nile, have a typical triangular shape, like the
Greek letter 

29. Mississippi Birdfoot Delta
Source: NASA

30. Ganges-Brahmaputra River Delta
From Landsat 7 WRS Path 137 Row 44, center: 23.12, Image taken 2/28/2000

31. Fluvial Processes and Landscapes at Different Stream Stages
Youthful
Steep hillsides,
drainage divides predominant,
V-shaped valleys
Headward erosion,
stream downcutting –
vertical erosion
Mature
Rounded hills,
valley walls predominant,
graded streams,
broad floodplains
Lateral erosion,
streams adjust to discharge/load
Old age
Floodplains, ox-bow lakes,
deltas and alluvial plains,
very low relief
Deposition,
sluggish stream flow,
poor drainage

32. Los Angeles River Now!
2005 Flood