Chapter 5

Question 1

Weathering

Answer 1

Physical/chemical breakdown of rock at or near the surface of the Earth to produce sediment.

Question 2

Mass wasting

Answer 2

Transfer of that material downhill under influence of gravity.

Question 3

Erosion

Answer 3

Sediment movement by water, ice or wind

Question 4

Deposition

Answer 4

Sediment reaches a location where it accumulates

Question 5

Lithification

Answer 5

Sediment turns into sedimentary rock

Question 6

Mechanical weathering

Answer 6

Breaks the rock into smaller pieces by increasing surface area to allow chemical weathering to be more effective

Question 7

Frost wedging

Answer 7

Water expands by 9% when it freezes and exerts pressure to break rock. Broken rock falls down to form talus.

Question 8

Sheeting

Answer 8

Granite at the surface breaks into sheets/onion like layers due to pressure release. Temperature cycles create exfoliation domes.

Question 9

Chemical weathering

Answer 9

Chemical reactions breakdown rock and ends with chemical sediment, ions dissolved in water. Hot and wet environments accelerate process.

Question 10

Dissolution

Answer 10

1. Electrostatic forces allow ions to be removed from solid. Pure water dissolves rock and the presence of a small amount of acid increases the effect.

Question 11

Oxidation

Answer 11

Iron minerals that will break down when exposed to the atmosphere

Question 12

Hydrolysis

Answer 12

Hydrogen ions react with and replace positive ions.

Question 13

Spheroidal weathering

Answer 13

Manifestation of chemical weathering where sharp corners have more surface area per unit volume than flat surfaces. Chemical weathering is faster on corners and produces a smooth shape.

Question 14

Regolith

Answer 14

Layer of rock and mineral fragments formed by weathering. Unconsolidated material that is mechanically weaker than the bedrock. Very thin, or non-existent in the Arctic and up to 5m thick in mountains. Thickest in sedimentary basins and along major rivers.

Question 15

Soil

Answer 15

Interface between lithosphere, biosphere, hydrosphere and atmosphere. A combination of minerals and organic material in the upper part of the regolith.

Question 16

Good soil

Answer 16

50% mineral matter and humus (decayed animal and plants), 25% air, 25% water.

Question 17

Parent material

Answer 17

Influences rate of soil formation (slower on bedrock, faster on unconsolidated material). Chemical makeup controls chemistry of soil and fertility. Different climates can produce different soil from the same parental material.

Question 18

Time

Answer 18

Initially, soil composition depends on the parent material. After, climate will have a greater effect.

Question 19

Climate

Answer 19

Temperature and precipitation. Most important soil influence

Question 20

Topography

Answer 20

Soil moves down a steep dry slope by erosion and does not develop. Lowlands will have higher moisture content and plenty of time to develop.

Question 21

Plants and animals

Answer 21

High organic content in a forest or bog, low organic content in a desert. Fungi, bacteria, worms etc… Influence soil composition and formation.

Question 22

Soil profiles

Answer 22

Soil formation is a top-down process and results in layers known as horizons.

Question 23

Horizon sequence

Answer 23

OAEBC

Question 24

O horizon

Answer 24

Layer of organic material

Question 25

A horizon

Answer 25

Mineral matter.

Question 26

E horizon

Answer 26

Layer of light colored minerals. Eluviation and leaching

Question 27

B horizon

Answer 27

Layer of precipitates.

Question 28

C horizon

Answer 28

Layer of altered parent material.

Question 29

True Soil (solum)

Answer 29

Horizons OAEB

Question 30

Top Soil

Answer 30

Horizons OA

Question 31

Pedalfer soil

Answer 31

Develops in a relatively humid, wet climate (forests). Calcium carbonate leached downwards by acidic conditions. B-horizon enriched in iron oxides and aluminum rich clays.
Found in SE Canada, Pacific coast and eastern United States.

Question 32

Pedocal soil

Answer 32

Found in relatively dry areas with grassland vegetation. Calcium carbonate leached upwards and precipitated.
Found in the Canadian Prairies (Edmonton).

Question 33

Laterite soil

Answer 33

Develops in hot, wet tropical climates. Intense leaching of calcium carbonate and silica. Leaves upper soil concentrated in aluminum and iron that gives red color. Minimal humus, not good for agriculture.

Question 34

Chernozemic

Answer 34

Central Alberta has drier climate than Northern Alberta. Pedocal soil

Question 35

Luvisolic

Answer 35

Northwest Alberta has wetter climate, Rocky Mountains are lower. Pedalfer soil

Question 36

Cryosolic

Answer 36

Permafrost regions, mature soil does not develop

Question 37

Soil erosion

Answer 37

Affected by rain, gullies, humans, rivers wind, etc…