Unit Five - Weathering and Erosion - Weathering

Question 1

What is weathering?

Answer 1

The breakdown of rock at or near the Earth’s surface.

Question 2

What are sediments?

Answer 2

Smaller pieces of rock that have undergone weathering.

Question 3

What are the three causes of the weathering of rocks?

Answer 3

1. Air
2. Water
3. Actions of Living Things

Question 4

What is Chemical Weathering?

Answer 4

The breakdown of rock through a change in mineral or chemical composition.

Question 5

When does chemical weathering increase? Why?

Answer 5

The rate of chemical weathering increases in warm and moist climates.

A warmer Earth increases the rate of chemical weathering both by causing more rainfall and by speeding up the chemical reactions between rainwater and rock.

Question 6

What is Oxidation? (Def.)

Answer 6

It is the rusting of a material because of the interaction of iron and oxygen.

Question 7

What type of weathering is oxidation?

Answer 7

It is a type of chemical weathering because when a rock rusts, its because the iron in the material is exposed to the atom, oxygen. This chemically changes the rock because the composition changes to iron oxide.

Question 8

How does water affect a rock?(4 ways)

Answer 8

1. Water+ Carbon Dioxide = Carbonic Acid (dissolves any rock especially limestone)
2. Frost Action
3. Can weather, smooth, erode, and deposit rock through a running river
4. Water itself can dissolve anything

Water is sometime called the universal solvent because given enough time, it can dissolve anything.

Question 9

What is a sinkhole?

Answer 9

1. A natrual depression in land.
2. Collapse of a cavern roof
3. This happens because water dissolves the solid particles

Cavern roof means the top of a cave

Question 10

What is Physical Weathering?

Answer 10

The breakdown of rock into smaller pieces without chemical change.

Question 11

What is Abrasion

Answer 11

Occurs when rock particles grind against each other.

Sandpaper, Nailfile

Question 12

What is a charactersistic of abrasion and what are the four causes?

Answer 12

Rounded shaped rocks, when sediments are moved by

1. Ice
2. Running water
3. Gravity
4. Air

Question 13

What is Frost Action?

Answer 13

A type of Physical Weathering process caused by cycles of freezing and thawing of water in rock openings. Water infiltrates cracks in the bedrock and when it freezes, it expands 10%, causing the rock to split apart.

Question 14

Definition of Infiltration

Answer 14

The process which water penetrates into soil or rock.

Question 15

What is plant root growth?

Answer 15

As plants grow in a rock, they can also spread cracks apart even further.

Question 16

What are abrupt temperature changes.

Answer 16

Temperature increases, the rock expands and fractures.