Mass Wasting

Question 1

mass wasting (mass movement)

Answer 1

when large quantities of rock or soil move downhill under the influence of gravity;
includes landslides, rock falls, and slumps;
can be slow or rapid

Question 2

4 general types of mass wasting events

Answer 2

Falls, slides, slow flows, and rapid flows

Question 3

factors contributing to mass wasting

Answer 3

high relief
slope
lack of vegetation
water
seismic activity
amount of previous weathering
character of the bedrock

Question 4

relief

Answer 4

the distance between the
highest and lowest point in a
landscape

Question 5

slope

Answer 5

the angle of the land surface

Question 6

rockfalls (and soilfalls)

Answer 6

happen when material is undercut and a large section of the overlying material drops through the air

Question 7

talus

Answer 7

a large pile of debris that accumulates at the base of a cliff after a fall

Question 8

slides (landslides)

Answer 8

a general term for when rock or soil slides down a slope

Question 9

rock slides

Answer 9

can be a single block of material that slides down a hillside, or they can be composed of many rocks

Question 10

The difference between slides and slumps

Answer 10

slides generally travel down flat, planar surfaces, whereas slumps move along curved surfaces

Question 11

Slump

Answer 11

a rock slide along a curved surface

Question 12

scarp

Answer 12

The cliff face generally left on the hillside after a slide or slump

Question 13

Rock creep

Answer 13

occurs when some rocks that are more pliable slightly bend over time

Question 14

soil creep

Answer 14

occurs when soil particles
closer to the surface move faster than particles closer to the ground

Question 15

Signs of soil creep

Answer 15

bent tree trunks, tilted fence posts or gravestones, sections of road out of place etc.

Question 16

True or False: Rock creep is more common than soil creep

Answer 16

False: it’s the other way around

Question 17

solifluction

Answer 17

a special process that happens in arctic areas where there is permafrost; the water in the soil above the permafrost cannot flow down into the earth, so it begins to flow downhill, carrying the soil and anything on it with it

Question 18

Examples of rapid flows

Answer 18

Snow avalanches
rock avalanches
debris avalanches

Question 19

Debris avalanches

Answer 19

a mixture of rock and other debris

Question 20

Turbidities are recognized by the ____ ____

Answer 20

Bouma Sequence

Question 21

Turbidity currents/turbidity flows

Answer 21

dense, rapid flows that occur underwater

Question 22

Turbidities

Answer 22

Deposits formed by turbidity flows

Question 23

True or False: It is also possible to have large, underwater
debris flows that are laminar

Answer 23

True

Question 24

Examples of non-underwater rapid flows

Answer 24

Earth flows
mudflows
debris flows

Question 25

Earth flows

Answer 25

occur when soil and other unconsolidated materials become extemely water-saturated and begin to flow downhill

Question 26

Mudflows

Answer 26

happen anytime large quantities of dry soil or volcanic ash are mixed with large volumes of water. They become extremely dense and can float things like boulders and houses. They move very quickly like a flash flood, but they have the consistency of wet cement.

Question 27

Debris flows

Answer 27

have smaller quantities of water than mudflows