6. Rock

Question 1

What is a rock?

Answer 1

A coherent, naturally occurring solid consisting of minerals (or naturally occurring amorphous material).

Question 2

What are the rock types?

Answer 2

Igneous rocks, sedimentary rocks and metamorphic rocks

Question 3

How do igneous rocks form?

Answer 3

Igneous rocks (= magmatic rocks)

• Form when (fluent) magma cools to solid material:
• crystallisation to crystalline rocks or
• solidification into rocks composed of amorphous material
• There are two groups of igneous rocks: plutonic and volcanic
• Examples: granite , basalt

Question 4

How do sedimentary rocks form?

Answer 4

They form from particles that are deposited by sedimentary processes (ex: transport by water or wind)
- Examples: sandstone, limestone

Question 5

How do metamorphic rocks form?

Answer 5

The form as a result of mineralogical and / or textural alteration of rocks at high pressure and temperature.
- New metamorphic rocks can be formed from igneous,
sedimentary, or metamorphic rocks
- Examples: gneiss, schist

Question 6

What are the most important things that happens in the rock cycle?

Answer 6

• Melting
• Magma
• Crystallisation or solidification
• Igneous rock
• Uplift of plutonic rocks, metamorphic rocks or sedimentary rocks
• Weathering and erosion
• Transport
• Deposition
• Sediment
• Diagenesis (lithification)
• Sedimentary rocks
• Burial
• Metamorphism of sedimentary, igneous or metamorphic rocks
• Metamorphic rock