Deck 13: Unsafe Ground: Landslides and Other Mass Movements

Question 1

Mass wasting always involves a sudden movement of material downslope.

Answer 1

False

Question 2

Which of the following types of mass movement is least coherent (most like a liquid)?

A) slump
B) creep
C) rock slide
D) mudflow

Answer 2

D

Question 3

A rock slide into a reservoir triggered catastrophic flooding of the landscape below which dam?

A) Vaiont (Italy)
B) Aswan (Egypt)
C) Hoover (Nevada)
D) Glen Canyon (Arizona)

Answer 3

A

Question 4

For dry sediments,the angle of repose is approximately ____________ degrees.

A) 10
B) 15
C) 20
D) 30

Question 5

The immediate cause of incidents of mass movement is ____________.

A) electromagnetic attraction
B) gravitation
C) magnetism
D) friction

Question 6

Which of the following types of mass movement is likely to move most rapidly?

A) slump
B) creep
C) rock slide
D) debris slide

Question 7

Mass movement along coastal cliffs in southern California is so common because ____________.

A) the region is along an active margin with frequent earthquakes
B) the region is dry and the slopes support little or no vegetation
C) much of the rock in southern California is fractured
D) All of the above are correct.

Question 8

Which of the following factors DECREASES the risk of mass movement?

A) nearby earthquakes
B) excavation into the base of a hill
C) adding weight to the top of a hill
D) adding vegetation to the side of a hill

Question 9

To the geologist,____________.

A) landslides and mass movements are the same thing
B) all mass movements are landslides, but not all landslides are mass movements
C) all landslides are mass movements, but not all mass movements are landslides
D) mass movements differ from landslides in that a greater mass of material moves during a mass movement than during a landslide

Question 10

The principal difference between a debris flow and a debris slide is ____________.

A) the shape of the path taken by the moving mass
B) the grain size of the moving mass
C) that the former mass contains abundant water whereas the latter is dry
D) that the former mass contains pyroclastic debris from a volcanic eruption

Question 11

The principal difference between a debris flow and a mudflow is ____________.

A) the shape of the path taken by the moving mass
B) the grain size of the moving mass
C) that the former mass contains abundant water whereas the latter is dry
D) that the former mass contains pyroclastic debris from a volcanic eruption

Question 12

The principal difference between a lahar and a mudflow is ____________.

A) the shape of the path taken by the moving mass
B) the grain size of the moving mass
C) that the former mass contains abundant water whereas the latter is dry
D) that the former mass contains pyroclastic debris from a volcanic eruption

Question 13

The principal difference between a debris slide and a debris avalanche is ____________.

A) the shape of the path taken by the moving mass
B) the grain size of the moving mass
C) that the former mass contains abundant water whereas the latter is dry
D) that the former mass contains pyroclastic debris from a volcanic eruption

Question 14

The principal difference between a slump and a debris slide is ____________.

A) the shape of the path taken by the moving mass
B) the grain size of the moving mass
C) that the former mass contains abundant water whereas the latter is dry
D) that the former mass contains pyroclastic debris from a volcanic eruption

Question 15

Which of the following types of mass movement takes place most gradually?

A) slump
B) creep
C) rock slide
D) mudflow

Question 16

Which type of bedrock provides the greatest risk of landslide?

A) granite
B) gneiss
C) sandstone
D) shale

Question 17

One of the most problematic aspects of landslides is that large-scale,cataclysmic examples are the norm,whereas small-scale landslides are much rarer.

Question 18

Moisture among sediment grains ____________.

A) always increases the likelihood of mass wasting
B) always decreases the likelihood of mass wasting
C) can promote stability if present in small amounts, but promotes mass wasting if sediment is saturated
D) can promote stability if the grains are saturated, but a small amount of moisture has little effect on the likelihood of mass wasting

Question 19

Which of the following types of mass movement always travels down a curved surface?

A) slump
B) creep
C) rock slide
D) mudflow

Question 20

Which type of mass movement includes a large proportion of ash derived from a volcanic eruption?

A) stromboli
B) lahar
C) debris flow
D) wadi