UK's main rock types

Question 1

What are the UK’s 3 main rock types

Answer 1

• Sedimentary
• Igneous
• Metamorphic

Question 2

What are sedimentary rock’s characteristics

Answer 2

• Have layers
• Often contain fossils
• Great variety of colour
• Made of particles that may be the same size or may differ

Question 3

How are sedimentary rocks formed

Answer 3

• Formed in layers
• Many are formed from weathered or eroded rock debris that has been transported and deposited
• The deposited rock grains build up in layers called sediments
• The weight of the sediments cause the layers at the bottom to become compacted, forming rocks such as sandstone
• Chalk is formed by dead sea creatures being compacted on the sea bed

Question 4

Where is sedimentary rock found in the UK

Answer 4

• Chalk is found mainly in the east and southeast of England.
• Sandstone is found in southwest of England, the west of England bordering Wales and parts of northern England

Question 5

What are igneous rock’s characteristics

Answer 5

• Made from randomly arranged crystals
• Very hard resistant rock
• Does not contain fossils
• May be intrusive (formed inside the Earth) such as granite or;
• extrusive (formed on the Earth’s surface) such as basalt

Question 6

How are igneous rocks formed

Answer 6

• Formed from molten rock called magma that is found inside the Earth
• When magma cools, it forms igneous rocks
• If magma cools underground, it cools slowly forming rocks that contain large crystals such as granite
• If magma erupts from a volcano it cools quickly forming rocks that contain small crystals such as basalt

Question 7

Where is igneous rock found in the UK

Answer 7

• Basalt is found to the far north of England e.g. Whin Sill and the northern part of Northern Ireland e.g Giant’s Causeway.
• Granite is found in parts of North West Scotland, Devon and Cornwall in South West England, and Northern Ireland

Question 8

What is metamorphic rock’s characteristics

Answer 8

• It has crystals that can be arranged in layers for example, slate, which is formed from shale
• It can contain fossils, although the fossils are usually squeezed out of shape e.g. marble

Question 9

How are metamorphic rocks formed

Answer 9

• They form when igneous or sedimentary rocks are put under great pressure or are close to a source of heat
• The rocks are not melted but are heated
• Under these two conditions, the minerals within the rock change chemically to form a new type of rock.

Question 10

Where is metamorphic rock found in the UK

Answer 10

• Small amounts of slate are found in Northern Wales, South West England, and Northern Ireland
• Small amounts of schist are found in north west Scotland and northern Ireland