TYPES OF IGNEOUS ROCKS
EARTH AND LIFE SCIENCE
QUARTER I

DEPARTMENT OF EDUCATION
Learning Competency:
• Compare and contrast the formation of the
different types of igneous rocks S11/12ES-
Ic-18
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DEPARTMENT OF EDUCATION
Igneous Rocks
Igneous rocks
- are rocks that have formed out of
magma (molten rock)
- felsic or mafic
- coarse-grained or fine-grained
- intrusive or extrusive
ex: granite and basalt.
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DEPARTMENT OF EDUCATION
• There are many different types of igneous
rocks. They all have in common that they
were all once melted, and have since
cooled down and become solid.
• Igneous rocks look different because of
two factors: they cooled at different rates
and the "Mother" Magma (original melted
rock) was different.
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DEPARTMENT OF EDUCATION
• Rocks that are cooled outside of the
volcano are called volcanic rocks, and
those that cool inside the lithosphere are
called plutonic rocks.
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DEPARTMENT OF EDUCATION 6
Types of Igneous Rocks
1. Intrusive igneous rocks
- are formed when the magma hardens
before an eruption occurs through the
process called Plutonism. Different rock
materials allow the formation of intrusive
igneous rocks. The most common example
is granite.

DEPARTMENT OF EDUCATION 7
Granite is used in floor tiles and monuments. Granite is a
rock that typically looks pink and white with black specks.

DEPARTMENT OF EDUCATION
2. Extrusive igneous rocks
– are formed when the lava cools and
solidifies on the Earth surface through the
process called volcanism. The texture of
these rock is finer as compared to the
intrusive igneous rocks. Due to slow cooling
of the lava, large crystals are formed on the
rocks. The most common example is basalt.
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DEPARTMENT OF EDUCATION 9
Basalt is used for construction purposes such as
pavements, railroads, and road base. Basalt generally just
looks black.

DEPARTMENT OF EDUCATION
Questions:
1. What are the two types of igneous rocks?
2. Compare plutonism and volcanism as to
igneous rock formation.
3. Fill in the table with the data needed.
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CATEGORY TYPES OF IGNEOUS
ROCKS
1. Location of cooling and solidification
2. Rate of cooling
3. Size of crystals formed
4. Texture

DEPARTMENT OF EDUCATION
References:
• https://www.brighthub.com/environment/science-
environmental/articles/96398.aspx#
• https://msnucleus.org/membership/html/k-
6/pt/volcanoes/5/ptv5_2a.html
• www.quipperschool.com
• Earth and Life Science TG pp. 57-59
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THANK YOU!