Deck 6: Weathering and Soil

Question 1

A(n)________ is a common boundary where different parts of a system interact.

A)sphere
B)interface
C)delineation
D)geosphere

Answer 1

B

Question 2

________ is decayed remains of plant and animal life.

A)Regolith
B)Gravel
C)Amino Acids
D)Humus

Answer 2

D

Question 3

________ weathering occurs when differences in resistance or environmental factors produce uneven surfaces on rocks.

A)Chemical
B)Differential
C)Spheroidal
D)Mechanical

Answer 3

B

Question 4

Which of the following components makes up the largest percentage of most soils?

A)Mineral portion
B)Pores filled with water
C)Organic portion
D)Pores filled with air

Question 5

During hydrolysis, ________ commonly decompose into clay minerals, silica, and soluble constituents.

A)feldspars
B)halides
C)ferromagnesians
D)carbonates

Question 6

________ weathering is when there is a chemical transformation of rock into other compounds.

A)Mechanical
B)Chemical
C)Spheroidal
D)Differential

Question 7

Which climate contains the optimum environment for chemical weathering?

A)Cold and dry
B)Warm and dry
C)Cold and wet
D)Warm and wet

Question 8

________ and ________ are chemical weathering products created in many metal and coal mining regions and pose serious environmental hazards.

A)Carbonic acid; slag
B)Nitric acid; coal dust
C)Hydrochloric acid; bicarbonate
D)Sulfuric acid; iron oxide

Question 9

Which of the following rocks will be most resistant to weathering?

A)Solid bedrock
B)Jointed bedrock
C)Bedrock with solution weathering
D)Bedrock with sheeting

Question 10

Which acid is commonly responsible for the dissolution of limestone?

A)Nitric
B)Carbonic
C)Sulfuric
D)Hydrochloric

Question 11

________ is a soil that has bedrock as its parent material.

A)Humus
B)Residual soil
C)Regolith
D)Transported soil

Question 12

________ is the upper few feet of regolith that contains minerals and organic matter, water, and air and is capable of sustaining life.

A)Horizon
B)Humus
C)Soil
D)Sediment

Question 13

Rainwater will combine with which atmospheric gas in order to create carbonic acid?

A)Methane
B)Oxygen
C)Carbon dioxide
D)Carbon monoxide

Question 14

Which of the following is not an agent of erosion?

A)Running water
B)Heat
C)Ice
D)Wind

Question 15

________ weathering is when physical forces break solid rock into smaller sediments.

A)Mechanical
B)Chemical
C)Spheroidal
D)Differential

Question 16

Which chemical weathering process is the primary method of weathering for feldspars?

A)Dissolution
B)Oxidation
C)Frost Wedging
D)Hydrolysis

Question 17

Which of the following regions has the least likelihood of experiencing weathering via salt crystal growth?

A)Arid deserts
B)Rocky shorelines along the ocean
C)Subterranean cave passages
D)Roadways cleared of snow by the spread of halite

Question 18

Soil develops in response to interactions between which Earth spheres?

A)Hydrosphere and atmosphere
B)Geosphere, atmosphere, and biosphere
C)Geosphere, hydrosphere, and atmosphere
D)Biosphere, atmosphere, geosphere, and hydrosphere

Question 19

What environmental condition is reduced on a batholith in order to generate weathering via sheeting?

A)Heat
B)Moisture
C)Pressure
D)Mineral content

Question 20

What is the most important agent of chemical weathering?

A)Salt
B)Heat
C)Wind
D)Water

Question 21

Which of the following is a good method to reduce soil erosion as a result of strong winds?

A)Planting grass in natural drainageways
B)Creating terraces on steep slopes
C)Planting rows of trees and shrubs
D)Plant rows for crops that are oriented straight up the slope

Question 22

________ is a soil that has unconsolidated sediment as its parent material.

A)Humus
B)Residual soil
C)Regolith
D)Transported soil

Question 23

What is the definition of sheet erosion?

A)The removal of soil particles by wind gusts
B)Water moving in thin sheets, carrying dislodged soil particles
C)Removal of sheets of rock through exfoliation
D)Transportation of vegetation from rapidly eroding sediments

Question 24

________ is considered the most influential control of soil formation

A)Parent material
B)Plants
C)Climate
D)Time

Question 25

A soil's parent material can consist of weathered mineral matter.

Question 26

What is the definition of eluviation?

A)Decayed organic material
B)Accumulation of fine clay particles in a soil column
C)Downward transportation of fine clay particles in a soil column
D)The collective term for the O, A, E, and B horizons

Question 27

Which horizons make up the solum?

A)C horizon
B)O and A horizons
C)E, B, and C horizons
D)O, A, E, and B horizons

Question 28

Which soil horizon can hold more water due to the accumulation of fine clay particles?

A)A horizon
B)B horizon
C)O horizon
D)E horizon

Question 29

Which of the following is a good soil conservation method to reduce the loss of topsoil on gentle slopes that are farmed?

A)Planting crops parallel to the contours of the slope.
B)Leaving crop residues (i.e., stalks)in place in the field.
C)Planting grass in natural drainageways on the slope.
D)All of these choices are good for soil conservation.

Question 30

Chemical weathering will break down a rock by changing the molecular compounds that make up the rock.

Question 31

Water expands when it freezes.

Question 32

Weathering is the transportation or removal of broken-down materials.

Question 33

Organic acids can chemically weather a rock.Where would these acids originate?

A)Decay of granite
B)Thermal reaction between water and limestone
C)Secretion from and decay of vegetation
D)Leaching from the E horizon

Question 34

Oxidation is an effective method to weather iron in olivine.However, what must happen first to free the iron?

A)Root wedging to break up the olivine
B)Melting of the olivine
C)Dissolution of olivine
D)Hydrolysis acting on the olivine

Question 35

What effect will roots have on a sedimentary rock?

A)Root tips will promote cementation, making the rock stronger.
B)Roots will weaken the cement, splitting the rock apart.
C)Roots will wrap around the sediments, holding them tight as the rock cements.
D)Roots will add cement to unconsolidated sediments to create a rock.

Question 36

________ are the primary source of organic matter in soils.

A)Earthworms
B)Microorganisms
C)Plants
D)Mammals

Question 37

The longer a soil has been forming, the ________ it becomes and the ________ it resembles the parent material.

A)thinner; less
B)thinner; more
C)thicker; more
D)thicker; less

Question 38

Can soils can be eroded from distant sources and deposited as soil in new locations?

A)Yes, they are made of sediments and can be transported like sediments.
B)No, soils develop in place through the complex weathering of sediments and other materials.
C)Yes, the processes of transportation help to break down larger sediments to make soils.
D)No, once a soil is created in a location, it cannot be weathered and eroded.

Question 39

Why is soil a nonrenewable resource?

A)Because it forms very slowly
B)Because there is a limited amount of soil on the Earth and it cannot be replaced
C)Because it is not commonly used for human commerce
D)Because it cannot be privately owned

Question 40

Which horizons make up the topsoil?

A)C horizon
B)O and A horizons
C)E, B, and C horizons
D)O, A, E, and B horizons

Question 41

What is the surface area of the cube? (Hint: What is the formula for the area of a square? How many sides does a cube have?)

Question 42

Decades ago, a brick factory used to be located along a river.Waste materials and faulty bricks were piled along the banks of the river, and some of them fell into the water.Years later, some of these materials were removed.The bricks were still recognizable as bricks, some with the manufacturer's mark clearly visible on the front, but the edges and corners were rounded over.Why were the edges and corners of the bricks so rounded over while the faces of the bricks were largely untouched?

Question 43

How will joints in rock aid chemical weathering?

Question 44

The Dust Bowl disaster of the 1930s was one of the greatest ecological and agricultural disasters in American history, resulting in thousands of deaths and a historic mass migration.The causes of the Dust Bowl, however, were both natural and man-made.Discuss the causes of the Dust Bowl and rate their severity.In your opinion, which do you think were the most powerful and did the most damage to the soil?

Question 45

Mature soils are characteristic of steep slopes.

Question 46

Fine-grained particles or iron oxide accounts for red, yellow, and brown colors in soil horizons.

Question 47

A vertical succession of soil horizons is called a soil profile.

Question 48

How are humans agents of weathering and erosion?

Question 49

An order has arrived that the original cube must be broken down into eight cubic pieces of marble, all of the same dimension of 6 square feet per cube.What is the total surface area of the marble now?

Question 50

Explain how climate can affect the other four controls of soil formation.

Question 51

Mount Rushmore National Memorial was created at the height of the Great Depression in the 1930s by the use of explosives and jackhammers to sculpt granitic igneous rock.Which category of weathering (mechanical or chemical)best describes how the rock was broken down? Explain why you believe this is so.

Question 52

In the process of hydration, the entire water molecule is added to the mineral structure, stretching the crystal lattice.Which type of weathering would this process describe: physical or chemical? Why?

Question 53

Because weathering involves the destruction of geologic materials, many people view the process as a bad thing.However, weathering can also be viewed as a positive process.Provide an example of one positive aspect of weathering that makes the processes not only important, but necessary.Explain.

Question 54

Compare and contrast the state of soil development at the following three locations: mountaintops, foothills, bottomlands.

Question 55

Thermal expansion and thermal contraction are two processes where the presence of heat will weather a rock, breaking it into smaller pieces.In which category of weathering would you expect to find thermal expansion and contraction? Why?

Question 56

Using the order of crystallization on the Bowen's reaction Series, rate the resistance of silicate minerals to chemical weathering.In other words, which mineral(s)weather first and why? And last?

Question 57

A burrowing animal is digging its tunnel through rocky soil, moving fresh material to the surface.How is this animal contributing to the weathering of that material?

Question 58

Why are tropical rainforest soils poor for farming?

Question 59

What erosion control practices would be best suited for a landscape with steep slopes? With gentle, rolling hills?

Question 60

Why would a pile of gravel weather faster than a single solid boulder?

Question 61

Study this image and think about what the climate is like in this region.Which weathering process would you assume is responsible for material A?

A)Dissolution
B)Hydrolysis
C)Frost wedging
D)Exfoliation

Question 62

Assume the image above is in southern Arizona and rather than seeing patches of snow, you are seeing a desert.Which weathering process would you then assume is responsible for material A?

A)Salt crystal growth
B)Hydrolysis
C)Frost wedging
D)Exfoliation

Question 63

Which weathering process is illustrated in this image?

A)Exfoliation
B)Root wedging
C)Hydrolysis
D)Frost wedging

Question 64

Which soil formation characteristic will most strongly influence a soil when it is young? When it is old?

Question 65

A cemetery in New England contains headstones from the seventeenth to the twenty-first centuries.Headstones from the seventeenth century are made of slate.Headstones from the mid-nineteenth century are made of marble.The information on the seventeenth-century headstone is clear and easy to read, whereas the nineteenth-century headstone is now illegible.Why? What weathering has occurred?

Question 66

How does slope orientation affect soil development? (Hint: Which slopes receive the most sunlight?)

Question 67

What are the five controls of soil formation?