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Name________________________________Date_______Period_____
Igneous Rock Identification
Objective:
You will determine the name of unknown Igneous Rocks based
upon their physical characteristics using the Earth Science
Reference Tables.
Materials:
Directions:
Unknown Igneous Rock Samples, Earth Science Reference Tables
For each unknown Igneous Rock, identify the key physical
characteristics. Using your Earth Science Reference Tables,
determine the name of the Igneous rock based on the observed
characteristics.
Vocabulary:
Igneous Rock___________________________________________________
Intrusive_______________________________________________________
Extrusive______________________________________________________
Felsic_________________________________________________________
Mafic__________________________________________________________
Lava__________________________________________________________
Magma________________________________________________________
Vesicular______________________________________________________
Igneous Rock Identification
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Color
Sample A
Texture (check all that apply)
Density
 Light (felsic)
 Coarse
 Low
 Middle
(intermediate)
 Fine
 Medium
 Glassy
 High
 Dark (mafic)
 Vesicular
What is the environment of formation for this rock _______________________
Some minerals present in sample are ___________________________________
Based on the observations above Sample A is ___________________________
Color
Sample B
Texture (check all that apply)
Density
 Light (felsic)
 Coarse
 Low
 Middle
(intermediate)
 Fine
 Medium
 Glassy
 High
 Dark (mafic)
 Vesicular
What is the environment of formation for this rock _______________________
Some minerals present in sample are ___________________________________
Based on the observations above Sample B is ___________________________
Color
Sample C
Texture (check all that apply)
Density
 Light (felsic)
 Coarse
 Low
 Middle
(intermediate)
 Fine
 Medium
 Glassy
 High
 Dark (mafic)
 Vesicular
What is the environment of formation for this rock _______________________
Some minerals present in sample are ___________________________________
Based on the observations above Sample C is ___________________________
Igneous Rock Identification
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Color
Sample D
Texture (check all that apply)
Density
 Light (felsic)
 Coarse
 Low
 Middle
(intermediate)
 Fine
 Medium
 Glassy
 High
 Dark (mafic)
 Vesicular
What is the environment of formation for this rock _______________________
Some minerals present in sample are ___________________________________
Based on the observations above Sample D is ___________________________
Color
Sample E
Texture (check all that apply)
Density
 Light (felsic)
 Coarse
 Low
 Middle
(intermediate)
 Fine
 Medium
 Glassy
 High
 Dark (mafic)
 Vesicular
What is the environment of formation for this rock _______________________
Some minerals present in sample are ___________________________________
Based on the observations above Sample E is ___________________________
Color
Sample F
Texture (check all that apply)
Density
 Light (felsic)
 Coarse
 Low
 Middle
(intermediate)
 Fine
 Medium
 Glassy
 High
 Dark (mafic)
 Vesicular
What is the environment of formation for this rock _______________________
Some minerals present in sample are ___________________________________
Based on the observations above Sample F is ___________________________
Igneous Rock Identification
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Color
Sample G
Texture (check all that apply)
Density
 Light (felsic)
 Coarse
 Low
 Middle
(intermediate)
 Fine
 Medium
 Glassy
 High
 Dark (mafic)
 Vesicular
What is the environment of formation for this rock _______________________
Some minerals present in sample are ___________________________________
Based on the observations above Sample G is ___________________________
Color
Sample H
Texture (check all that apply)
Density
 Light (felsic)
 Coarse
 Low
 Middle
(intermediate)
 Fine
 Medium
 Glassy
 High
 Dark (mafic)
 Vesicular
What is the environment of formation for this rock _______________________
Some minerals present in sample are ___________________________________
Based on the observations above Sample H is ___________________________
Color
Sample I
Texture (check all that apply)
Density
 Light (felsic)
 Coarse
 Low
 Middle
(intermediate)
 Fine
 Medium
 Glassy
 High
 Dark (mafic)
 Vesicular
What is the environment of formation for this rock _______________________
Some minerals present in sample are ___________________________________
Based on the observations above Sample I is ___________________________
Igneous Rock Identification
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Color
Sample J
Texture (check all that apply)
Density
 Light (felsic)
 Coarse
 Low
 Middle
(intermediate)
 Fine
 Medium
 Glassy
 High
 Dark (mafic)
 Vesicular
What is the environment of formation for this rock _______________________
Some minerals present in sample are ___________________________________
Based on the observations above Sample J is ___________________________
Discussion Questions (Answer in FULL sentences!!)
1.
Explain HOW cooling rate affects crystal size._________________________
________________________________________________________________
________________________________________________________________
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2.
What is the difference between Intrusive and Extrusive Igneous Rocks?
________________________________________________________________
________________________________________________________________
________________________________________________________________
3.
Explain the difference between Felsic and Mafic Igneous Rocks.
________________________________________________________________
________________________________________________________________
________________________________________________________________
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4.
Describe the Igneous Rock Pegmatite.
________________________________________________________________
________________________________________________________________
________________________________________________________________
5.
Why do some Extrusive Igneous Rocks contain no crystals?
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________________________________________________________________
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6.
On the diagram below, place the number of the following rocks where they
could be found. Dashed lines indicate where plutonic rocks would form.
1 - Granite
2 - Basalt
3 - Obsidian
4 - Gabbro
5 - Diorite
6 - Pumice
7 - Scoria
8 - Pegmatite
Ocean
Igneous Rock Identification
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