Chapter 11 Weathering, Karst Landscapes, & Mass Movement

Question 1

Physical Weathering

Answer 1

Frost Wedging
Salt-Crystal Growth
Exfoliation
Root Wedging

Question 2

Factors that influence weathering

Answer 2

• Rock Composition and Structure
• Climate (Precipitation and Temperature)
• Slope Orientation
• Subsurface Water
• Vegetation

Question 3

Chemical Weathering

Answer 3

Spheroidal Weathering
Hydration
Hydrolysis
Oxidation "Rusting"
Dissolution of Carbonates

Question 4

Solution Sinkhole

Answer 4

Forms due to gradual dissolution of
carbonate rock
- Depths of 7-330 feet; 33-3300 feet wide

Question 5

Collapse Sinkhole

Answer 5

When a solution sinkhole collapses
through roof of underground cavern
- Develops over hours or days
- Common in Florida

Question 6

Denudation

Answer 6

Any process that wears away or rearranges landforms

Question 7

Bedrock

Answer 7

Solid, consolidated rock

Question 8

Regolith

Answer 8

Rock fragments; broken up

Question 9

Soil

Answer 9

Rock fragments and finer particles;

dirt; developed from parent material

Question 10

Physical Weathering:

Frost Wedging

Answer 10

Water penetrates rock through pores (holes) and joints

- When water freezes, it expands; causes wedges in rock to break

Question 11

Physical Weathering:

Salt-Crystal Growth

Answer 11

Water is easily evaporated in arid regions

- When water evaporates, salt is left behind in pores and joints

Question 12

Physical Weathering:

Exfoliation

Answer 12

Rock peeling or slipping off in sheets

• Shedding of the outer layer
• Similar to losing outer layers of an onion

Question 13

Physical Weathering:

Root Wedging

Answer 13

Roots create joints in rock; wedge them apart

Question 14

Chemical Weathering:

Spheroidal Weathering

Answer 14

Causes the softening and rounding of rock

- Water penetrates rock joints and dissolves or cements weaker minerals

Question 15

Chemical Weathering:

Hydration

Answer 15

Minerals combining with water

- Structural change; little chemical change

Question 16

Chemical Weathering:

Hydrolysis

Answer 16

Decomposition of chemicals

with water reaction

Question 17

Chemical Weathering:

Oxidation

Answer 17

“Burning” of metals in rock due to reactions with oxygen (rusting)
- Weakens bonds that holds minerals together

Question 18

Chemical Weathering:

Dissolution of Carbonates

Answer 18

Weathering of rock with calcium carbonate by a weak acid

• Limestone common example
• Water vapor dissolves carbon dioxide

Question 19

Geography of Weathering

Answer 19

More active in lower latitudes
- Heat, moisture, vegetation are abundant
• Frost action
- Occurs primarily in higher latitudes and elevations
• Salt Wedging
- Occurs primarily in arid regions

Question 20

Mass Movement

Answer 20

Downslope movement of material
• Made up of soil, sediment, or rock
• Gravity and water are primary forces
• Short distance (up to a few miles)

Question 21

Mass Movement:

Slope

Answer 21

An inclined surface that rock

material moves down

Question 22

Mass Movement:

Conditions for Slope Failure

Answer 22

Saturation by heavy rainfall

Volcanic eruption melts ice and snow

Question 23

Mass Movement:

Rockfall

Answer 23

Volume of rock that falls; hits surface

- Forms Talus Slope: Cone-shaped piles of broken rocks

Question 24

Mass Movement:

Debris Avalanches

Answer 24

Mass of tumbling rock, debris, soil

• Ice and water move debris
• Danger from rapid speed

Question 25

Mass Movement:

Earthflow

Answer 25

Movement of fine-grained material

- A scarp (cliff) created at top of hillside

Question 26

Mass Movement:

Mudflow

Answer 26

Movement of very watery fine-grained rock material

• Flows like liquid
• Faster than earthflows

Question 27

Mass Movement:

Soil Creep

Answer 27

Slowest of all mass movement

• Movement of soil/regolith overtime
• Soil particles lifted and disturbed

Question 28

Mass Movement:

Landslide/Rockslide

Answer 28

Occur more rapidly than soil creeps and flows (within minutes)
- Occur on steep slopes

Question 29

What type of physical weathering is limited to arid regions?

Answer 29

Salt Crystal Growth