Chapter 14 River Systems and Landforms

River Systems and Landforms Fluvial Processes and Landscapes   Streamflow Characteristics   Floods and River Management  

Fluvial Processes: stream related processes Alluvium: a general term for the clay, silt, and sand transported by running water. 

Base Levels Figure 14.2

A Drainage Basin: a geographical area where precipitation contributes to the discharge of a particular stream Figure 14.3

Continental divide (blue line) separate major drainage basins into Pacific, Atlantic, Gulf of Mexico, Arctic ocean. Figure 14.5

Streamflow Characteristics Stream Gradient: decline in elevation from its headwaters to its mouth Stream Erosion   Stream Transport   Flow and Channel Characteristics   Stream Deposition  

Stream’s erosion Hydraulic action: the work of water moving material Abrasion: debris moves with water that mechanically erodes the stream bed

Meandering Stream Features Figure 14.17

Meandering Stream Profile Erosion occurs Deposition occurs Figure 14.15

Meandering Stream Development Oxbow lake: a lake was formerly a part of the channel of a meandering stream, isolated when it was cut off through the neck of a looping meander Figure 14.16

Itkillik River, Alaska Figure 14.16

Three ways of fluvial transports Figure 14.13

Braided Stream: if the load exceeds the stream’s capacity, sediments accumulates as the aggradation and the stream channel builds up through the deposition. Figure 14.14

An Ideal Longitudinal Profile Figure 14.18

Nickpoint Figure 14.20

Retreat of Niagara Falls Figure 14.21

Floodplain: the flat, low-lying area along a stream channel that is subject to recurrent flooding alluvial deposits mask the underlying rocks Natural Levees (French: rising): high elevated land along a stream channel that consists of sand-sized particles Figure 14.23

Mississippi River Levee Break Figure 14.24

Alluvial Terraces: leveled areas that appear as topographic steps above the stream, created by a stream as it scours with renewed downcutting into its floodplain. Figure 14.25

Ganges River Delta River delta: a triangular-shaped deposited plain formed at the mouth of a river Figure 14.26

Nile River Delta Figure 14.27

Mississippi River Delta Figure 14.28

Mississippi River Delta Copyright © 2006 Pearson Prentice Hall, Inc. Figure 14.28

Streamflow Measurement Figure 14.32

Urban Flooding Figure 14.33