UNIT 12 :
SELF DIRECTED LEARNING
CHONG BOON SECONDARY
SEC 1 GEOGRAPHY
• 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.
• 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)
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
•Formed when magma cools and
•Can be above or beneath the
COARSE GRAINED IGNEOUS ROCKS
•Developed below Earth’s surface.
•Slow rate of cooling, forming
•Large crystals formed.
• Made of quartz, feldspar and mica.
FINE-GRAINED IGNEOUS ROCKS
• Magma cools near the surface or on
• High speed of cooling forming fine
• Crystals are small in size.
• Dark in colour,
•Formed by layering of materials
that layer on land or sea floor.
•Compacted by weight of the
•Over time, the layers fuse and
become Sedimentary Rocks
•Variety in grain size, colour and
•Formed from compression of
organic and inorganic materials.
•Occasionally possible to have
• Sandstone, mudstone, shale,
• Rocks subjected to intense pressures
• Crustal movements produce great
pressure, changing the properties of
• Igneous and Sedimentary rocks can
both be changed into metamorphic
• Limestone -> Marble
• Shale -> Slate
THE ROCK CYCLE
•Shows the relationship between
the 3 rock types.
•Rocks change types with the
• Weathering and Erosion
• Compaction and Cementation.
• Melting and Cooling
• Heat and Pressure
ROCK TYPES IN SINGAPORE
•Take a look at the diagram on pg
•Memorise the locations where you
find the most Igneous rocks, where
you would find more Sedimentary
rocks and where you would find
QUESTIONS IN REVIEW
•What are rocks
•How are the 3 rock types formed
•Name examples of each type of
•How does the rock cycle explain
the relationship between the
different types of rock.
•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.