Physical Geography
Chapter 12 Learning Objectives and Study Questions
1. List the three common processes by which a steam erodes its channel and describe a situation under
which each erosional process would be particularly effective.
2. Describe the three types of load a stream transports and indicate how you might obtain a sample of
each.
3. Briefly explain how a stream attempting to remain graded will respond if its load or capacity are
changed, and how braided and meandering channels develop in response to particular
load/capacity situations.
4. Briefly explain under what conditions a meandering stream will develop an oxbow lake, entrenched
meander or alluvial terraces.
5. Explain why streams build alluvial fans at the mouths of steep canyons in arid environments; what
factors lead to sediment deposition at these sites?
1. Streams do the work of erosion by abrasion, corrosion and _____.
A. deflation
B. excavation
C. hydraulic action
D. outsourcing
E. quarrying
2. Streams carry sand and gravel primarily as _____ load.
A. bed
B. dissolved
C. over
D. suspended
E. wide
3. A graded stream attempts to balance its load with its _____.
A. capacity
B. competency
C. corrosion
D. discharge
E. velocity
4. The Fall River in Rocky Mountain National Park
(shown in accompanying photo) has a/an _____
channel.
A. braided
B. incised
C. meandering
D. overgrown
E. straight
5. Braided channels form where a stream’s _____
exceeds its capacity.
A. discharge
B. competency
C. gradient
D. load
E. velocity
6. In response to rapid uplift or a sudden drop in base level, streams cut into their own floodplain
deposits to produce _____.
A. alluvial terraces
B. badlands
C. entrenched meanders
D. gullies
E. rills
7. Streams deposit sediment and build alluvial fans in
response to decreases in all of the following except their
_____.
A. capacities
B. discharges
C. dissolved loads
D. gradients
E. velocities
8. In arid regions, ephemeral lakes that form in closed
basins—as well as the dry beds left behind when they evaporate—are known as _____.
A. badlands
B. oases
C. playas
D. sinks
E. sumps