What mass movement is most likely to occur in a geological setting where the rock strata are inclined?
a) debris flow
b) slump
c) creep
d) rockslide
rockslide
____ denotes the exposed, crescent shaped rupture surface at the head of a slump.
a) scoop
b) sole
c) toe
d) scarp
scarp
Consider a weathered rock or soil particle lying on a slope. How will the gravitational force pulling the particle downward along the land surface vary with the inclination of the slope?
a) it will increase as the slope angle is lessened
b) it will decrease as the slope angle is lessened
c) it is not affected by the slope angle
d) it will possibly increase or decrease as slope angle is lessened, depending upon other factors
it will decrease as the slope angle is lessened
How do the strength and cohesion of clay-rich regolith or soil change with the addition of water?
a) water does not affect the cohesion but lowers the strength
b) water reduces the strength of clays but raises the cohesion of the soil
c) water increases the strength and cohesion
d) water lowers the strength and cohesion
water lowers the strength and cohesion
____ involves movement on a zone of compressed air.
a) a slump
b) a mudflow
c) a rock avalanche
d) soil creep
a rock avalanche
Of the following, which one would most likely be triggered by an earthquake?
a) solifluction
b)soil creep
c) slump
d) rock avalanche
rock avalanche
Which one of the following operates primarily in the areas of a permafrost?
a) rock avalanch
b) solifluction
c) soil creep
d) mudflow
solifluction
Consider a steep highway cut made by removing slightly weathered to fresh, fractured, granite bedrock. Which of the following situations is most stable against rockslides?
a) one set of widely spaced, sub-horizontal fracture
b) two sets of fractures, one inclined toward the road cut and the other away
c) two sets of fractures one widely spaced and sub-horizontal, the other inclined away from the cut
d) one set of widely spaced fractures inclined towards the road cut
One set of widely space, sub-horizontal fractures
All of the following are possible indicators that creep is occuring except for ____
a)tilted fences or power-line poles
b) an extremely thick soil profile
c) curved tree trunks
d) cracks in road or sidewalks
an extremely thick soil profile
How do freezing, thawing, wetting, and drying contribute to soil creep?
a) the soil becomes much weaker when dry and frozen
b) gravity exerts a much stronger force when the soil is wet and thawed
c) the soil expands and contracts, lifting particles and dropping them a slight distance downslope
d) eventually, these cause the soil and regolith to suddenly slide down the slope
the soil expands and contracts, lifting particles and dropping them a slight distance downslope
Why was the Alaskan pipeline built above ground and insulated?
a) to protect the pipeline against damage due to thawing ground and to keep the crude oil hot and fluid
b) to keep the oil cool and highl fluid
c) to protect against damage from herds of elk and deer
d) to protect against damage from roots of large trees uprooted in windstorms
to protect the pipeline against damage due to thawing ground and to keep the crude oil hot and fluid
A geologist wants to locate a horizontal coal bed on a soil-covered slope where soil creep is active. A distinctive sandstone bed underlies the coal bed. On the basis of weathered sandstone fragments in the soil, where is the coal bed?
a) just below the lowest piece of sandstone seen in the soil
b) just above the highest piece of sandstone seen in the soil
c) just below the highest piece of sandstone seen in the soil
d) just aboce the lowest piece of sandstone seen in the soil
just above the highest piece of sandstone seen in the soil
Which of the following statements concerning mudflow is not true?
a) mudflow may be caused by heavy rains or melting snow
b) in hilly areas, mudflows move down the canyons and stream valleys
c) mudflows deposit talus slopes
d) mudflows can move and carry very large boulders and other coarse debris
mudflows deposit talus slopes
Which statement best describes slumping, a mass wasting process?
a) a block or blocks of unconsolidated regolith slide downhill along a curved slip surface
b) blocks of hard bedrock slide downhill along fracture surfaces
c) the soil and regolith move downhill very slowly
d) a mass of soil or regolith becomes saturated with water and suddenly flows downhill to the base of the slope
a block or blocks of unconsolidated regolith slide downhill along a curved slip surface
Which mass wasting process has the slowest rate of movement?
a) slump
b) rock avalanche
c) solifluction
d) creep
creep
All of the following are factors affecting mass wasting except for ____.
a) gravity
b) water
c) slope angle
d) geological age
geological age
The most rapid type of mass movement is a ____.
a) slump
b) lahar
c) rock avalanche
d) debris flow
rock avalanche
As an erosional process, how is mass wasting unique from wind, water, and ice?
a) mass wasting affects particles of all sizes whereas the others only smaller particles
b) mass wasting does not require a transporting medium
c) mass wasting affects much larger geographic areas than does wind, water, and ice
d) all of the above make mass wasting unique compared to wind, water, and ice.
mass wasting does not require a transporting medium
T/F Slump describes the very slow, downhill movement of soil and regolith.
false
T/F The steepest, stable, slope angle possible in unconsolidated , granular materials like sand and gravel is called the angle of retention.
false
T/F Solifluction occurs during the warmer summer months.
true
T/F Bedding planes and fractures can both act as slip surfaces for rockslides.
true
T/F Repeated freezing and thawing can be important in soil creep movements.
true
T/F Lahars are essntially mudflows associated with volcaones and volcanism.
true
Solifluction is an important mass wasting process in areas of permafrost.
true
T/F A triggering mechanism, such as heavy rains or an earthquake, are necessary for mass wasting to occur.
false
T/F A scarp is the exposed portion of the rupture surface beneath a slump block.
true
T/F Earthflows and slumps generally involve movement of unconsolidated or weakly consolidated soil and regolith.
true
What form of mass wasting is illustration #29?
a) debris flow
b) creep
c) earthflow
d) rockslide
e) slump
slump
What form of mass wasting is illustration #30?
a) debris flow
b) creep
c) earthflow
d) rockslide
e) slump
rockslide
What form of mass wasting is illustration #31?
a) debris flow
b) creep
c) earthflow
d) rockslide
e) slump
debris flow
What form of mass wasting is illustration #32?
a) debris flow
b) creep
c) earthflow
d) rockslide
e) slump
earthflow
What form of mass wasting is illustration #33?
a) debris flow
b) creep
c) earthflow
d) rockslide
e) slump
creep