The Rock Cycle
Year 6 students investigate the three types of rocks — igneous, sedimentary, and metamorphic — and how the rock cycle describes the continuous transformation of rocks over geological time.
What You Need to Know
Key Concept Diagram
Igneous rocks form when magma or lava cools and solidifies (e.g. granite, basalt)
Sedimentary rocks form when sediments are deposited in layers and compacted over time (e.g. sandstone, limestone)
Metamorphic rocks form when existing rocks are changed by intense heat and/or pressure deep in the Earth (e.g. marble, slate)
The rock cycle is a continuous process: rocks can be transformed from one type to another through melting, weathering, erosion, deposition, and heat/pressure
Key Vocabulary
Igneous rock
Rock formed by the cooling and solidification of magma or lava
Sedimentary rock
Rock formed from layers of sediment that have been compacted and cemented over time
Metamorphic rock
Rock that has been transformed by heat and/or pressure without melting
Weathering
The breakdown of rocks at Earth's surface by physical, chemical, or biological processes
Knowledge Check
Select the correct answer for each question. Click "Check Answer" to see if you are right.
Question 1
Which type of rock is formed when lava cools quickly on Earth's surface?
Question 2
Sandstone is an example of which type of rock?
Question 3
What process in the rock cycle turns sedimentary rock into metamorphic rock?
Key Concepts Summary
- ●Igneous rocks form when magma or lava cools and solidifies (e.g. granite, basalt)
- ●Sedimentary rocks form when sediments are deposited in layers and compacted over time (e.g. sandstone, limestone)
- ●Metamorphic rocks form when existing rocks are changed by intense heat and/or pressure deep in the Earth (e.g. marble, slate)
- ●The rock cycle is a continuous process: rocks can be transformed from one type to another through melting, weathering, erosion, deposition, and heat/pressure