Download Igneous Rocks

Guided Notes
Rocks & Minerals
What isisaaMineral
1.What
Mineral
Mineral
Tests
2.Mineral
Properties
Rock Cycle
3.Rock
Cycle
Igneous Rocks
4.Igneous
Rocks
Sedimentary Rocks
5.Sedimentary
Rocks
6.Metamorphic
MetamorphicRocks
Rocks
Reference Tables
© K. Coder 2015
8. What are igneous rocks?
• Igneous Rocks: rocks formed by the
solidification of molten material (magma
or lava)
• You must know how to use ESRT page 6:
Scheme for Igneous Rock Identification
Names of Igneous Rocks
Form on
Earth’s
surface
Form
below Earth’s
surface
Rate of
cooling
Fast
Slow
Rocks in the same row have the same crystal
size and texture. Read directly to the right of
the rock name for this information.
Rate of
cooling
Fast
Slow
9. What are the two locations igneous rocks can form? Fill in!
Extrusive
Environment of
Formation
Volcanic
Also Known As…
On Earth’s surface
Location
Fast
Rate of Cooling
Less than 1 mm or
none
Size of Crystals
Glassy/fine/vesicular
Texture
Obsidian, Basalt,
Pumice
Examples
Intrusive
Plutonic
Glassy Texture - Obsidian
Fine Texture - Basalt
© K. Coder 2015
Coarse Texture - Granite
Very Coarse Texture - Pegmatite
© K. Coder 2015
9. What are the two locations igneous rocks can form? • Vesicular: a rock with gas pockets (holes)
formed when gas bubbles became
trapped in rapidly cooling lava
Pumice
Vesicular Basalt
© K. Coder 2015
Rate of
cooling
Fast
Slow
Rocks in the same
column have similar
color, density,
composition, and
mineral composition.
Read directly below
the rock name to the
bottom chart for this
information.
© K. Coder 2015
Any pattern found
below the rock
name is mineral
within this rock.
10. What are igneous rocks composed of?
• Chemistry of Igneous Rocks: depends upon the presence
Fill in
of certain elements
Aluminum (Al) &
Silicon (Si)
Dominating Elements
Felsic
Composition
Light color
Color
Low density
Density
Obsidian (color exception)
Pumice
Granite
Examples
Iron (Fe) and
Magnesium (Mg)
Felsic Rocks
Granite
Pumice
Rhyolite
Mafic Rocks
Gabbro
Scoria
Basalt
11. What are the key features of an igneous rock?
Fill in
✓ Review – Igneous Rock Identification: 1) The flowchart below shows the formation of
some igneous rocks. Letters A through I
indicate parts of the flowchart that have not
been labeled. Using your knowledge of
igneous rocks and ESRT page 6, fill in the
blanks for letters A through I.
✓ Checkpoint – Igneous Rock Identification: © K. Coder 2015
✓ Review – Igneous Rock Identification: 2) The photograph below shows actual crystal sizes in a light-colored
igneous rock that contains several minerals, including potassium feldspar,
quartz, and biotite mica.
Which rock should this be identified as? __________________________
✓ Review – Igneous Rock Identification: 3) The diagrams below show the crystals of
four different rocks viewed through the same
hand lens. Which crystals most likely formed
from molten material that cooled and solidified
most rapidly?
✓ Review – Igneous Rock Identification: 4) What is the name of the extrusive, nonvesicular igneous rock with a fine texture and
a mineral composition of 35% quartz, 35%
potassium feldspar, 15% plagioclase feldspar,
10% biotite, and 5% amphibole?
✓ Review – Igneous Rock Identification: 5) Which rock most probably formed directly
from lava cooling quickly at Earth’s surface?