geology chapter 15 and 16
meanders
A stream with a low to moderate gradient, carrying most of its load in suspension, should be characterized by many curves and bends called
Natural levees raise the height of the stream channel, reducing the amount of flooding that will occur on the floodplain
How does the formation of a natural levee impact flooding?
canyons to widen
Over time, mass wasting causes __________.
regions underlain by permafrost
Solifluction would most likely occur in ____
regional flood
The Great Flood of 1993 in the Upper Mississippi River basin is an example of which type of flood?
headwaters
The ____ of a river have a steep gradient, high channel roughness, and low water volume
continental divide
The ________ is an elevational point that divides an entire continent into large drainage basins
drainage basin
The geographical area where all surface water converges to one location is called its
creeps
are very gradual mass movements in which the whole slope moves downhill slowly.
bed load, suspended load, dissolved load
What are the three types of loads carried by streams?
a flat surface next to a river channel
What is a floodplain?
water soaking into the ground
What is infiltration?
the fine-grained particles that travel in the water column above the stream bed
What is suspended load?
the steepest angle at which a material remains at rest
What is the angle of repose?
the amount of flow in contact with the banks and bed of the channel
What is the wetted perimeter of a stream?
shale
What rock type is the easiest for a river to cut through?
creep
Which is the slowest type of mass wasting?
mountains
Which landscape is most prone to generating landslides?
mouth
A delta forms at the ___ of a river, where the velocity of the water flow decreases and deposition is highest.
slide
A mass movement in which a cohesive block of earth or rock slips downhill relatively quickly in one piece along a zone of weakness is called a
floodplain
A river with a well-developed has a flat low-lying channel and experiences flooding during periods of high discharge.
strength and cohesion will decrease
A stream is flowing over a hill composed of clay-rich soil. The stream is eventually blocked to create a small pond in order to free land downhill for construction. What will happen to the strength and cohesion of the soil in the area around this pond?
The downslope movement of sediment and rock under the direct influence of gravity.
Define mass wasting.
slot canyon
A __________ is formed when vertical incision by a stream is the primary process, with relatively minimal mass wasting.
true
Creep is the most widespread mass-wasting process
rolling, sliding, bouncing
How can pieces of rock in contact with a stream bed move?
Water in pore spaces reduces cohesion between particles, Water makes the slope material heavier, Water can easily flow downslope
How can the addition of water make a slope fail, creating a landslide?
slump
Mass movements that move blocks of materials and unconsolidated materials down a curved surface creating scarps on a slope are known as
true
Maximum velocity occurs when the stream is at the bankful stage
bed
Particles moving by saltation are transported in the _______ load
false
Point bars are locations where erosion occurs whereas cutbanks are locations where deposition occurs
true
Rockfalls are the primary way in which talus slopes are built and maintained
corrosion
The process that causes dissolution of limestone bedrock in a stream is ______
discharge
The volume of water flowing past a certain point in a given amount of time is a river's
bedrock channel
Waterfalls are a characteristic of a ____
a ridge of flood deposits next to a river channel
What is a natural levee?
fall
When large rocks become dislodged and drop down a steep slope, the mass movement is called a
flow
When unconsolidated material moves downslope as a viscous fluid it is called a
The Colorado River erodes downward, then mass-wasting processes move material from high to low areas, then the Colorado River transports material downstream.
Which of the following correctly states the role of rivers and mass wasting in the formation of the Grand Canyon?
well-developed floodplain, meanders
Which of the following is a characteristic of a graded stream?
gravity
Which of the following is the major contributing factor in all landslides?
having a narrow, deep channel
Which of the following would increase flow velocity?
alluvial fan
Which sedimentary environment of deposition will be controlled in part by debris flows?
slump
Which type of mass wasting forms a crescent-shaped scar at the head of movement?
oversteepening a slope, a wildfire, adding water to sediments
____ is a trigger for mass wasting
competence
________ is a measure of a stream's ability to transport particles based on size rather than quantity
capacity
________ is the maximum load of solid particles a stream can transport per unit time