1. Rocks and the Rock Cycle
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2. Can you think of some places where rocks and minerals can be found?
… and what about in cities or towns?
Rocks and minerals are all around us.
It takes millions of years for rocks to form - we must use our natural resources wisely.
1. Creek beds, river banks, road cuts and railroad cuts, excavation sites, cliffs, beaches
2. Rock walls and buildings, brick buildings (made of clay), concrete buildings/ foot paths (made from limestone), glass windows (glass is made of sand), steel structures (Steel is made from iron ore).

3. Three Types of Rocks IGNEOUS (Latin for fire)
SEDIMENTARY (Latin for settle)
METAMORPHIC (Greek for change)
Igneous Latin for fire, sedimentary Latin for settle

4. Igneous Rocks
Formed when magma (the molten rock that lies under the earth’s crust) is forced to higher layers of the crust – cools & solidifies.
There are 2 types of igneous rocks – Intrusive & extrusive
INTRUSIVE - Formed when magma slowly solidifies inside earth. Takes thousands of years to harden. Not seen until surface rocks have been eroded away. Coarse-grained.
EXTRUSIVE – Formed when magma ERUPTS from volcanoes or escapes through cracks to form lava. Lava cools quickly – and forms into rocks. Fine-grained, e.g. Pumice and basalt.
Intrusive rocks cool slowly underground. Extrusive rocks cool within a couple of weeks of reaching surface.

5. DEFINITION
Igneous rock is a volcanic rock that forms when magma cools and hardens. Intrusive igneous rock solidifies underground. Extrusive igneous rock solidifies above ground.
Igneous is Latin for fire
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6. Igneous Rocks Volcanic eruption Earth’s Surface Igneous Rock
Molten Rock
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LET’S VIEW A VOLCANIC ERRUPTION!!!

7. Sedimentary Rocks
Erosion --> rocks and minerals break down into small pieces called sediments.
Carried by ‘the elements’ & deposited in river beds or sea beds.
Accumulate (build-up) in layers --> pressed together by weight of new sediments. Compressed sediments are ‘cemented’ & harden to form new rock.

8. Sedimentary Rocks
Have you ever noticed layers or bands in rocks? These are the layers of sediment.
Examples:
Sandstone, limestone, chalk and shale
Fossils are often found in sedimentary rocks.
Why do you think this might be?

9. DEFINITION
Sedimentary rock is a rock formed near Earth’s surface from pieces of other rocks, plant or animal remains, or by the build-up of chemical solids.
Latin for settle
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10. Sedimentary Rocks Sea Land Weight and pressure of sediment particles
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11. Metamorphic Rocks
Igneous and sedimentary rocks can be changed into a different kind of rock by extreme heat or pressure – the changed rock is called metamorphic rock.
Original rock may be forced into new arrangements, sometimes new minerals form.
Metamorphic rocks can also change again.
Examples:
Shale --> Slate Limestone --> Marble
Granite --> Granite gneiss Sandstone --> Quartzite
Changes in appearance or mineral composition

12. DEFINITION
Metamorphic rock is a rock formed by the transformation of existing rock, as a result of extreme heat and/ or pressure.
Greek for change
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13. Metamorphic Rocks
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14. The Rock Cycle
Rock is constantly being changed by; heat, pressure, melting, crystallization, compaction, cementation and weathering.
Move rock material through the states of; melts, igneous rock, sediments, sedimentary rock and metamorphic rock.
This natural and ongoing cycle is known as the rock cycle.
Animation of the rock cycle:

15. Displayed on IWB for Learners to Label