Deck 37: Mass Movements

Question 1

A main driving force for mass movements is:

A) gravity
B) wind
C) ice
D) chemical weathering

Answer 1

A

Question 2

Rocks, soil, and other unconsolidated materials continuously move downslope in quantities ranging from individual boulders to entire hillsides in all mountain zones.

Answer 2

True

Question 3

Slope failure will occur when materials exceed _____.

A) the angle of repose
B) the density of water
C) the strength of individual minerals in the materials
D) the strength of anchoring vegetation

Answer 3

A

Question 4

The resistance of geologic materials to movement, also known as their frictional strength, depends on:

A) type of material
B) weight of overlying block
C) the amount of water present
D) all of the above

Question 5

The component of gravity tending to push blocks of rock downhill parallel to the slope is termed:

A) frictional force
B) perpendicular stress
C) compressional force
D) shear stress

Question 6

The material that has the least cohesion is:

A) dry sand
B) clay
C) wet sand
D) a boulder

Question 7

High water content in soil or fractured rock will:

A) slightly increase slope stability
B) decrease slope stability
C) greatly increase slope stability
D) none of the above, water does not influence slope stability

Question 8

All of the following factors increase shear stress and trigger slope failure EXCEPT:

A) road cuts into steep slopes
B) streams that deepen mountainous valleys
C) earthquake shaking
D) grading steep slopes into step-like structures

Question 9

The downslope movement of material is termed mass movement. What type of mass movement involves snow and ice?

A) debris flow
B) snow fall
C) avalanche
D) slump

Question 10

Creep involves movement of soil:

A) at a rapid speed
B) at a slow, almost imperceptible pace
C) rapidly at first, then slowly later
D) slowly at first, then rapidly speeds up

Question 11

The type of slide involves blocks of rocks moving along curved surfaces is a:

A) rockslide
B) slump
C) debris flow
D) rock fall

Question 12

In order to distinguish the difference between a slide and a slump, a geologist would:

A) determine the time of year the movement occurred
B) measure the volume of sediment or debris that has moved down
C) gather eyewitness accounts of what happened
D) examine the surface in which blocks of rock move down

Question 13

Slumps are common in:

A) shale and clay-rich rocks
B) hard sandstones
C) hard granites
D) volcanic rocks

Question 14

Erosion by rivers and road construction are examples of factors that may cause a decrease in slope angles thereby promoting mass movements.

Question 15

Which of the following is the fastest form of mass movement?

A) slide
B) flow
C) fall
D) solifluction

Question 16

A snow avalanche is considered what form of mass movement?

A) flow
B) slide
C) fall
D) debris flow