Chapter 3: Rocks And Weathering

Question 1

What are the 3 types of rocks?

Answer 1

Sedimentary, igneous and metamorphic

Question 2

What are the 3 types of weathering?

Answer 2

Physical, chemical, biological

Question 3

How is physical weathering caused?

Answer 3

By physical processes

Question 4

Give some causes of physical weathering

Answer 4

Temp. Change, freeze-thaw and the effects of wind, rain+waves

Question 5

How does temp change cause physical weathering?

Answer 5

When a rock gets hot it expands and when it gets cold it contracts. Cracks can form and pieces of rock will fall away, this happens particularly in deserts

Question 6

How do wind, rain and waves cause physical weathering?

Answer 6

Wind blows tiny grains of sand against rock and over time this weathers it. Rain and waves crash against them wearing them away

Question 7

How does freeze-thaw action cause physical weathering?

Answer 7

If water gets into a crack in a rock then freezes, it expands and this can continue until the crack becomes big enough to crack the rock apart

Question 8

Give a form of chemical weathering

Answer 8

Acid rain, it harms fish and trees, but speeds up chemical weathering up a lot. It’s worse when the rock is limestone over granite

Question 9

How is biological weathering caused?

Answer 9

Animals and plants, for example a rabbit could burrow into a rock and weather it

Question 10

How can people cause biological weathering?

Answer 10

Just by walking, over time paths In the countryside have become damaged because of the boots and shoes wearing them away

Question 11

What is erosion?

Answer 11

The movement of the broken pieces away from the site of weathering

Question 12

What is weathering?

Answer 12

The wearing away of rocks

Question 13

How are igneous rocks formed?

Answer 13

From molten rock that has cooled and solidified.

Question 14

How is the igneous rock basalt formed?

Answer 14

Extrusively, this means that the lava has cooled quickly above the ground forming small crystals

Question 15

How is the rock granite formed?

Answer 15

Intrusively, this means that magma has slowly cooled underground and eventually has become exposed when the rocks above have seared away, therefore large crystals have formed because its slower and they have more time to make bonds and connections

Question 16

How are metamorphic rocks formed?

Answer 16

They are the result of increased pressure acting on existing rocks over a long period of time

Question 17

What are some examples of metamorphic rocks?

Answer 17

Marble
Slate
Schist

Question 18

What may rocks include?

Answer 18

Tiny crystals and some layers

Question 19

How are sedimentary rocks formed?

Answer 19

Layers of sediment laid down in lakes or seas over millions of years

Question 20

Describe the process of the formation of sedimentary rocks?

Answer 20

Transported to the sea, deposited on a sea bed where they are compacted in a process called sedimentation

Question 21

Give an example of a sedimentary rock

Answer 21

Limestone= skeleton and shells of marine animals
Sandstone= compression of sand
Coal= fossils and dead trees/plants

Question 22

Give the order of the rock cycle

Answer 22

Weathering
Erosion
Transportation 
Deposition 
Compression and cementation
Heat and pressure 
Melting
Cooling
Exposure