Deck 6: Weathering, Erosion, and Soil

Question 1

Chemical weathering operates in wetter climates and mechanical weathering in drier climates.

Answer 1

False

Question 2

Hydrolysis impacts predominantly soluble minerals like carbonates.

Answer 2

False

Question 3

Solution weathering is aided by the fact that rainfall is naturally acidic.

Answer 3

True

Question 4

Soils are typically the result of one dominant chemical process.

Question 5

If soils are chemical weathering products, then parent material does not affect the type of soil that will develop.

Question 6

Particle size is the most critical variable affecting soil development.

Question 7

Pedalfers form in moist environments where aluminum (Al) and iron (Fe) can be leached from the soil.

Question 8

Weathering and erosion describe similar processes affecting earth materials.

Question 9

Weathering generally destroys natural resources so it is imperative to exploit resources before weathering occurs.

Question 10

Pressure release occurs under which of the following conditions?

A) humid and seasonal
B) hot and arid
C) cold and humid
D) within mountainous regions
E) in the tropics

Question 11

Chemical weathering is most effective in which combination of conditions?

A) cold and arid
B) warm and humid
C) warm and arid
D) humid and seasonal
E) cold and humid

Question 12

An important type of solution weathering is performed by

A) carbolic acid.
B) carbonic acid.
C) bicarbonate acid.
D) carbon dioxide acid.
E) sulfuric acid.

Question 13

Carbonic acid produces solution weathering of

A) sandstone.
B) rhyolite.
C) granite.
D) limestone.
E) shale.

Question 14

Which of the following is a type of chemical weathering?

A) hydrogenation
B) reduction
C) dissolution
D) solution
E) oxygenation

Question 15

An important soluble product of hydrolysis is

A) calcium.
B) sodium.
C) silica.
D) B and C, only.
E) all of the above.

Question 16

Pedocals develop

A) in arid regions.
B) in humid regions.
C) where chemical weathering is ineffective.
D) A and C, only
E) B and C only

Question 17

What ore of aluminum is commonly developed in tropical soils?

A) borax
B) bauxite
C) laterite
D) phosphate
E) manganese

Question 18

Which of the following are sometimes found as ore deposits formed by residual concentration in soils?

A) iron, sodium, potassium, nickel, tin, gold
B) silver, gold, magnesium, nickel, tin, diamonds, iron
C) clays, copper, manganese, potassium, calcium carbonate
D) gold, diamonds, phosphate, tin, iron, nickel, manganese
E) phosphate, sodium, calcium, silicon, iron, magnesium

Question 19

The minerals that form last in Bowen's reaction series are (more/less)___________ stable than those that form early.

Question 20

Windblown silt deposits called___________ have contributed to the formation of fertile soils in the Mississippi River valley and the Pacific Northwest.

Question 21

The ___________horizon is the zone in which weathering products accumulate.

Question 22

The___________ horizon consists of partially-altered parent material.

Question 23

The soils which develop in humid regions are called___________ .

Question 24

Pedocals contain (less/more)___________organic matter and (less/more)___________soluble minerals than do pedalfers.

Question 25

Weathering can result in the formation of ___________by the removal of soluble substances to produce a residual concentration of valuable minerals.

Question 26

Gossans have occasionally been used as sources of iron but they have much greater importance as indicators of underlying___________ ___________ .

Question 27

Kaolinite is a___________ formed from the weathering of ___________.

Question 28

Kaolinite is used in manufacturing ___________and ___________.

Question 29

___________ ___________ is a conservation practice whereby plant residue from the harvested crop is left on the ground.

Question 30

Erosion or decreased soil productivity results in ___________ ___________ .

Question 31

What is the relation between the effects of deforestation of the rainforests and the forest soils?

Question 32

Why is rainfall naturally acidic?

Question 33

Why are the soils developed on granite in Arizona different from the soils developed on granite in Virginia? Use examples where appropriate.

Question 34

Why is climate such an important factor controlling the characteristics and locations of soils?

Question 35

What factors contribute to the continuing large scale exploitation of tropical rainforests?

Question 36

How might deforestation affect climate?

Question 37

What important greenhouse gas is present in greater amount in the tropical rainforests than in all other vegetation?

Question 38

Define weathering.

Question 39

Name an important physical property about water that makes it unique among liquids.

Question 40

Why is this unique property of water important in the weathering of rocks?

Question 41

Global warming is predicted to occur from increased atmospheric carbon dioxide due to the burning of fossil fuels. How might this increased level of carbon dioxide affect rates of weathering?

Question 42

Why is all rainfall slightly acidic?

Question 43

What is a natural process that introduces gases into the atmosphere, to cause acid rain?

Question 44

What human activity contributes to the problem of acid rain?

Question 45

List five factors that control soil profile development and soil type.

Question 46

If soil erosion is as natural as soil formation, then why do we practice soil conservation?

Question 47

What is an economically very important mineral resource produced by intense chemical weathering and which is found only in laterite soils?

Question 48

Why do soils develop slightly faster on gentle and/or south facing slopes than on steep and/or north facing slopes?

Question 49

What is the maximal accepted rate of soil loss in the U.S., according to the U.S. Department of Agriculture and why?