Igneous rocks

Question 1

What are the two different types of igneous rocks give an example of both

Answer 1

Extrusive (Basalt) Intrusive (Granite)

Question 2

How are extrusive igneous rocks formed

Answer 2

Formed at constructive plate boundaries where magma cools and solidifies quickly near or on the earths surface repeatedly

Question 3

What percentage of the worlds extrusive igneous rock is basalt

Answer 3

90%

Question 4

What colour is basalt

Answer 4

Black or dark-grey with small crystals from rapid cooling

Question 5

What is the characteristics of basalt

Answer 5

Fine-grained, hard and erosion resistant

Question 6

What is the use of basalt

Answer 6

Road construction

Question 7

Why is basalt unsuitable for building construction

Answer 7

It lacks luster

Question 8

What happens if basalt is weathered

Answer 8

It makes deep fertile soil

Question 9

Where can you find basalt in Ireland

Answer 9

The Giant’s Causeway

Question 10

How is intrusive igneous rock formed

Answer 10

Formed at destructive plate boundaries where magma cools and solidifies slowly far below the earths surface, takes thousands of years to fully harden

Question 11

Name an intrusive igneous rock

Answer 11

Granite

Question 12

How is granite formed

Answer 12

When magma intrudes into gaps within in the earths crust (batholiths) slowly forming large crystal structures

Question 13

The three main minerals found in granite

Answer 13

Mica, feldspar and quartz

Question 14

How can the colour of granite vary

Answer 14

Normally dark-grey, variations in mineral content can alter its colour

Question 15

What are the characteristics of granite

Answer 15

Coarse-grained, hard and erosion resistant

Question 16

Use of granite

Answer 16

To face buildings or in the construction of bridges

Question 17

What happens if granite gets weathered

Answer 17

It produces kaolin/China clay used in porcelain

Question 18

Where can you find granite in Ireland

Answer 18

The Wicklow Mountains