cbss unit 12

1. UNIT 12 :
INVESTIGATING ROCKS
SELF DIRECTED LEARNING
CHAPTER
CHONG BOON SECONDARY
SCHOOL
SEC 1 GEOGRAPHY

2. GENERAL REMINDERS
• You are to read the information found on
this set of notes.
• You are to complete reading the entire Unit
12 of your text book.
• Express Students need to complete pg 93 to
100 of the textbook.
• Normal Academic Students need to
complete pg 93 to 96, 98 to 100.

3. UNIT OBJECTIVES
• By the end of this unit you will be able to
1. Identify and describe the 3 types of rocks
2. Identify and describe the main types of
rocks in Singapore.
3. Explain the components in the rock cycle.
(Express stream only)

4. WHAT ARE ROCKS
• The hard outer layer of the Earth’s crust.
• Made up of minerals
• Key characteristics include minerals,
hardness, colour, grain size and texture.
• 3 main groups of rocks
• Igneous Rocks
• Sedimentary Rocks
• Metamorphic Rocks

5. IGNEOUS ROCKS
•Formed when magma cools and
solidifies.
•Can be above or beneath the
Earth’s surface.
•Highly crystalline.

6. GRANITE

7. COARSE GRAINED IGNEOUS ROCKS
•Developed below Earth’s surface.
•Slow rate of cooling, forming
coarse grains.
•Large crystals formed.
•Granite
• Made of quartz, feldspar and mica.

8. FINE-GRAINED IGNEOUS ROCKS
• Magma cools near the surface or on
the surface.
• High speed of cooling forming fine
grained rocks.
• Crystals are small in size.
• Basalt
• Dark in colour,

9. SEDIMENTARY ROCKS
•Formed by layering of materials
that layer on land or sea floor.
•Compacted by weight of the
thick layers.
•Over time, the layers fuse and
become Sedimentary Rocks

10. CHARACTERISTICS
•Variety in grain size, colour and
textures
•Formed from compression of
organic and inorganic materials.
•Occasionally possible to have
fossils.
• Sandstone, mudstone, shale,
limestone

11. Sandstone
Limestone
Shale

12. METAMORPHIC ROCK
• Rocks subjected to intense pressures
and heat.
• Crustal movements produce great
pressure, changing the properties of
existing rocks.
• Igneous and Sedimentary rocks can
both be changed into metamorphic
rock.
• Limestone -> Marble
• Shale -> Slate

13. Slate

14. THE ROCK CYCLE
•Shows the relationship between
the 3 rock types.
•Rocks change types with the
following actions
• Weathering and Erosion
• Compaction and Cementation.
• Melting and Cooling
• Heat and Pressure
Express
Stream
ONLY

15. ROCK TYPES IN SINGAPORE
•Take a look at the diagram on pg
98.
•Memorise the locations where you
find the most Igneous rocks, where
you would find more Sedimentary
rocks and where you would find
Metamorphic rocks.

16. QUESTIONS IN REVIEW
•What are rocks
•How are the 3 rock types formed
•Name examples of each type of
rock
•How does the rock cycle explain
the relationship between the
different types of rock.

17. FINAL NOTE
•Read the chapter in the textbook.
•The next single period lesson you
will have your test.
•It will be only short answer
questions, no MCQ.
•Good luck!