Rocks and Minerals by UTH Rocks and Minerals by UTH    

Lesson 21: Intrusive Igneous Rocks

Directions

Study the lesson for one week.

Over the week:

• Read the lesson.
• Review the synopsis.
• Recite aloud the vocabulary words and their definitions.
• Study the rock and mineral of the week.
• Complete the enrichment activities.
• Study the review questions.

Synopsis

There are three major groups of rock that make up the crust of the Earth: igneous, metamorphic, and sedimentary. There are two subgroups of igneous rocks, those formed below the surface of the Earth (intrusive from magma) and those formed on the surface (extrusive from lava). Intrusive rocks tend to have larger crystals than extrusive, as they cool slowly under the surface the Earth.

Vocabulary

Igneous Rock: A rock formed by the cooling of molten rock, either below the surface (intrusive) or on the surface (extrusive).
Intrusive Igneous Rock: Igneous rocks formed below the surface of the Earth from magma. The relatively slow cooling favors the development of large crystals.
Extrusive Igneous Rock: Igneous rocks formed above the surface of the Earth from lava. The relatively rapid cooling favors the formation of small crystals.

Rock or Mineral of the Week

Overview

• Diorite, an intrusive gray igneous rock, forms from magma below the surface of the Earth.
• Diorite is used in construction and for areas requiring drainage.

Interesting Facts

• There is a special form of diorite called orbicular diorite. 'Orbicular' means in the shape of a ring.
• See the striking natural ring patterns of orbicular diorite.

Enrichment

Activity 1: Narrate the Lesson

• After reading or listening to the lesson, narrate the lesson aloud using your own words.

Activity 2: Take a Nature Walk

• Embark on a nature walk.
• Collect one rock or mineral specimen.
• Use the gathered specimen to create the field book entry.

Activity 3: Complete a Field Book Entry   

After your nature walk, complete page 6 in 'Fifth Grade Science Rocks and Minerals Notebook Pages.'

Review

Question 1

What are the three major groups of rock that make up the crust of the Earth?

1 / 6

Answer 1

The three major groups of rock that make up the crust of the Earth are igneous, metamorphic, and sedimentary.

1 / 6

Question 2

Which rock group is formed from cooling magma or lava?

2 / 6

Answer 2

The igneous rock group is formed from cooling magma or lava.

2 / 6

Question 3

Which rock group includes rocks or minerals transformed by heat and pressure?

3 / 6

Answer 3

The metamorphic rock group includes rocks or minerals transformed by heat and pressure.

3 / 6

Question 4

Which rock group is made up of deposits cemented together?

4 / 6

Answer 4

The sedimentary rock group is made up of deposits cemented together.

4 / 6

Question 5

Is diorite an igneous, metamorphic, or sedimentary rock?

5 / 6

Answer 5

Diorite is an igneous rock.

5 / 6

Question 6

Is diorite formed from lava or magma?

6 / 6

Answer 6

Diorite is an intrusive igneous rock, so it forms underground from magma.

6 / 6

❮ ❯

1. What are the three major groups of rock that make up the crust of the Earth? The three major groups of rock that make up the crust of the Earth are igneous, metamorphic, and sedimentary.
2. Which rock group is formed from cooling magma or lava? The igneous rock group is formed from cooling magma or lava.
3. Which rock group includes rocks or minerals transformed by heat and pressure? The metamorphic rock group includes rocks or minerals transformed by heat and pressure.
4. Which rock group is made up of deposits cemented together? The sedimentary rock group is made up of deposits cemented together.
5. Is diorite an igneous, metamorphic, or sedimentary rock? Diorite is an igneous rock.
6. Is diorite formed from lava or magma? Diorite is an intrusive igneous rock, so it forms underground from magma.

References

'Close-up on orbicular granite, Caldera, Chile' by Dropus. CC BY-SA 4.0. Wikipedia. en.wikipedia.org/wiki/File:Close-up_on_orbicular_granite,_Caldera,_Chile.JPG. n.p.

'Close-up on orbicular granite, Caldera, Chile' by Herman Luyken. CC BY-SA 3.0. Wikipedia. commons.wikimedia.org/wiki/File:2005.11.08_005_Granito_Orbicular_Caldera_Chile.jpg. n.p.

'Diorite.' Wikipedia. en.wikipedia.org/wiki/Diorite. n.p.

Cited Physical Properties. Geology.com. geology.com/rocks. n.p.