Chapter 5 Weathering, Soil, and Mass Movements

Question 1

The process that occurs when physical forces break rock
into smaller pieces without changing the rock’s chemical
composition is called

Answer 1

mechanical weathering.

Question 2

Which of the following weathering processes involves the

constant freezing and thawing of water?

Answer 2

frost wedging

Question 3

The inscriptions on marble gravestones become harder and

harder to read over time. This is caused by

Answer 3

chemical weathering.

Question 4

When a rock is exposed to chemical weathering, it

Answer 4

changes into one or more new compounds.

Question 5

Which of the following is NOT a factor that affects the rate
of weathering in rocks?
a.	evolution
b.	rock characteristics
c.	climate
d.	amount of exposed area

Answer 5

evolution

Question 6

Chemical weathering is highest in areas that are

Answer 6

very warm and wet.

Question 7

Rock features such as the sculpted pinnacles seen in Bryce

Canyon National Park are the result of

Answer 7

differential weathering.

Question 8

Which of the following is NOT a major component of soil?

a. mineral matter
b. humus
c. air
d. earthworms

Answer 8

earthworms

Question 9

In general, the largest component of bog soils is

a. water.
b. organic matter.
c. air.
d. living organisms.

Answer 9

organic matter.

Question 10

Soil that forms on unconsolidated deposits is called

a. transported soil.
b. residual soil.
c. humus.
d. bedrock.

Answer 10

transported soil.

Question 11

Which of the following statements about soil formation
is true?
a. The longer a soil has been forming, the thinner it
becomes.
b. Precipitation affects the rate at which nutrients are
removed from soil.
c. Hot, wet climates produce a thin layer of chemically
weathered soil.
d. Cold, dry climates produce a thick layer of mechanically
weathered soil.

Answer 11

Precipitation affects the rate at which nutrients are

removed from soil.

Question 12

The main source of organic matter in soil is

Answer 12

plants.

Question 13

In which of the following areas will soil formation
be greatest?
a.	a steep slope in a warm, wet climate
b.	a flat area in a cold, wet climate
c.	a flat area in a warm, wet climate
d.	a north-facing area on a steep slope

Answer 13

a flat area in a warm, wet climate

Question 14

What kind of soil is found in the C horizon of a soil profile?

Answer 14

partially weathered parent material

Question 15

Pedalfer soils would most likely be found

a. on an island close to the equator.
b. in a tropical rainforest.
c. in the dry areas of the western United States.
d. in the eastern half of the United States.

Answer 15

in the eastern half of the United States.

Question 16

Laterite soils contain high amounts of

Answer 16

iron oxide.

Question 17

Since humans have been present, the amount of sediments
carried by rivers has
a.	increased by a factor of about 2.7.
b.	increased slightly.
c.	stayed about the same.
d.	decreased by about half.

Answer 17

increased by a factor of about 2.7.

Question 18

Which of the following is NOT true about mass movement?

a. Some mass movement is too slow to be seen.
b. Mass movement always leads to landslides.
c. Gravity is the driving force behind all mass movements.
d. Mass movement is always downslope.

Answer 18

Mass movement always leads to landslides.

Question 19

Oversteepened slopes often lead to mass movements
because
a. the angle of their slope is between 50 and 60 degrees.
b. plants cannot grow on them.
c. the angle of their slope is less than 50 degrees.
d. the angle of their slope is greater than 40 degrees.

Answer 19

the angle of their slope is greater than 40 degrees.

Question 20

A mass movement that involves the sudden movement of a

block of material is called a

Answer 20

slide.

Question 21

The process called _______ involves physical forces

that break rock into smaller pieces.

Answer 21

mechanical weathering

Question 22

One cause of chemical weathering is the ________
that dissolves in water and then reacts with many common
minerals, forming oxides.

Answer 22

carbonic acid

Question 23

________ weathering happens when different parts of

a rock mass weather at different rates.

Answer 23

Differential

Question 24

The air component in soil provides plants with the

needed for photosynthesis.

Answer 24

carbon dioxide

Question 25

A(n) ________ soil is made of equal parts of clay, silt,

and sand.

Answer 25

loamy

Question 26

During the process of soil formation, ________
decompose dead plant and animals, increasing the amount of
organic matter.

Answer 26

microorganisms

Question 27

On a steep slope, erosion is accelerated because there is not
enough moisture to sustain sufficient ________.

Answer 27

plant growth

Question 28

________ is a dense impenetrable layer found in the

B horizon of a soil profile.

Answer 28

Hardpan

Question 29

In a soil profile, the ________ layers contain parent

material that is hardly weathered at all.

Answer 29

deepest

Question 30

Large amounts of calcium carbonate are typical of

________ soil.

Answer 30

pedocal

Question 31

Human activities such as farming, ________, and
construction remove vegetation from the land and increase the
rate of erosion.

Answer 31

logging

Question 32

A landform called a stream valley is the most common result of
________.

Answer 32

mass movement

Question 33

One trigger of mass movements is the pores in sediments filling
with ________.

Answer 33

water

Question 34

One of the most dramatic triggers of sudden mass movements
is a(n) \_\_\_\_\_\_\_\_.

Answer 34

earthquake

Question 35

________, the slowest type of mass movement,

involves the lifting and contracting of soil particles over time.

Answer 35

Creep