Weathering and Soils

Question 1

Physical weathering

Answer 1

accomplished by physical forces that break rocks into smaller and smaller pieces without changing rock’s mineral composition

Question 2

Chemical weathering

Answer 2

a chemical transformation of rock into one or more new compounds

Question 3

Examples of physical weathering

Answer 3

Frost wedging; Biological activity; Unloading

Question 4

Examples of chemical weathering

Answer 4

Hydrolysis; Dissolution; Oxidation

Question 5

Hydrolysis

Answer 5

reacts with acid/ water to form clays

Question 6

Dissolution

Answer 6

carbonate (rock) and acid rain create calcium carbonate solution; Causes sinkholes and caves

Question 7

Oxidation

Answer 7

rock with O2 or groundwater with Fe is powerful agent that makes rock red

Question 8

Tropical

Answer 8

Strong chemical

Question 9

Polar

Answer 9

slight mechanical

Question 10

Desert

Answer 10

slight mechanical

Question 11

Mid-latitude

Answer 11

strong chemical and strong mechanical (Michigan)

Question 12

Differential erosion

Answer 12

Different rock types weather differently; Rocks weather at different rates of weakening due to exposure

Question 13

Granite

Answer 13

exfoliation; hydrolysis

Question 14

Basalt

Answer 14

Chemical (oxidation)

Question 15

Sandstone

Answer 15

granual disintegration

Question 16

Limestone

Answer 16

dissolution

Question 17

Shale

Answer 17

granual disintgration into clay

Question 18

Use of gravel

Answer 18

drains very fast

Question 19

Use of loam

Answer 19

best for plants; contains lots of organics

Question 20

Use of silt

Answer 20

oor aeration; compacts easily

Question 21

Use of Sand

Answer 21

drains fast

Question 22

use of clay

Answer 22

absorbs water; doesn’t let water pass through

Question 23

Leaching

Answer 23

soulable material washed away

Question 24

Eluviation

Answer 24

washes fine material downward

Question 25

Bioremediation

Answer 25

use of bacterium to consume and break down hydrocarbons and other pollutents in soil

Question 26

Pros of Bioremediation

Answer 26

Less costly; Minimum distruption of site; Enviormentally friendly

Question 27

Cons of Bioremediation

Answer 27

Slow response; Has to be specificly tailored to each site; Most successful in soil that maintains 70 degrees

Question 28

Thermal soil remediation

Answer 28

Heating contaminated material to evaporate hydrocarbon impurities and water

Question 29

Air Sparging

Answer 29

Large volumes of air injected into polluted soil to force pollutents outward then treated by carbon filter

Question 30

Encapsulation

Answer 30

Mixing polluted soil with lime, cement, and concrete

Question 31

Ways to conserve soil

Answer 31

No till farming; Put up break wall to protect from wind; "Let the land be your leader"

Question 32

"Keep it covered"

Answer 32

No till farming; Cover soil with mulch, plastic, or latex; Plants to protect top soil

Question 33

"Let the land be your leader"

Answer 33

follow natural topography; Like terracing

Question 34

Rockfall

Answer 34

Boulders; Frost wedging

Question 35

Rock slide

Answer 35

Sedimentary; Slides down bedding plane

Question 36

Avalanche

Answer 36

Fast movement of snow; Caused by weak layer of snow; Usually in Spring

Question 37

Mudflow

Answer 37

Clay mixed with water; Usually in Spring; Snow melt; Very fluid

Question 38

Lahar

Answer 38

Volcanic ash mixed with water

Question 39

Slump

Answer 39

Saturation of water causes soil below surface layer to drop downhill

Question 40

Creep

Answer 40

Slow movement of soil; Causes tiliting of objects; Due to freezing/thawing

Question 41

Solification

Answer 41

Arctic climates; Spring; When top layer melts, moves slowly over perma-frost

Question 42

Factors influencing mass movement

Answer 42

1. Amount of moisture; 2. Angle of slope; 3. Lack of vegetation; 4. Rock Type; 5. Roundness of Particle

Question 43

Angle of repose

Answer 43

maximum angle sediment can retain; Based on size and shape of particle; Large particle + large angle of repose

Question 44

Causes of landslide?

Answer 44

Moisture

Question 45

How to prevent Mass movement?

Answer 45

1. Fence/Wall; 2. Leaving enough space; 3. Planting Vegetation; 4. Provide good drainage (most expensive, but best way)

Question 46

Importance of Soil

Answer 46

Supports animal and plant life; Provides habitat for wide range of organisms; Influences distribution of plant species

Question 47

Factors controlling Soil Formation

Answer 47

1. Climate; 2. Organisms; 3. Relief (topography); Parent material; Time

Question 48

Pedalfer soil

Answer 48

Eastern United States; Contains Al + Fe; Has large Zone of Leaching; Under forest vegetation; Temperate humid climate; Brown colored, sandy

Question 49

Pedocal Soil

Answer 49

Western United States; Contains high levels of Calcium carbonate; Whitish in Color; Dry grasslands and brush vegetation; Temperate dry climate; Large Bedrock

Question 50

Laterite Soil

Answer 50

(Not much in USA); Hot and wet tropical climates; Intense chemical weathering; Lots of water; High in iron, Red color; Poor growing soil; Super thin top soil

Question 51

Which rocks weather the most rapidly?

Answer 51

Sedimentary; Because only lithified together

Question 52

What rocks weather the least? The exception?

Answer 52

Igneous and metamorphic; Marble is exception

Question 53

What mineral is most resistant to weathering?

Answer 53

Quartz