Download Igneous Rock Video

I. Formation
They are
formed when
hot, liquid rock,
or magma, cools
and solidifies
(Hardens)
II. Classification
Igneous rocks are classified according to
their composition and texture.
 4 basic types of textures

Glassy – black and sharp
Fine grained – interlocking pieces
Coarse grained – consist of interlocking
mineral crystals
Porphyritic – made of large crystals scattered
on the back of small crystals.
Igneous Rocks
Coarse-Grained
Granite
Gabbro
Fine-Grained
Rhyolite
Basalt
III. Magma vs.
Lava
Magma – molten material
below the earth’s surface.
Lava – molten material
above the earth’s surface.
A. Intrusive Igneous Rocks:
 Magma pushes into
surrounding rock below
the Earth’s surface
 Cools slower
 Large Crystals
 Think: (INSIDE)
Examples:
Did you know?!?!
Granite is
the most
abundant
intrusive
rock!
B. Extrusive Rocks:
 forms when magma
erupts onto the
Earth’s surface
(lava),
 cools quickly
 very small or no
crystals formed
 Think: (EXTERIOR)
Example:
Basalt is the most
common
EXTRUSIVE
igneous rock!
Did you know?!?!
Another
name for an
Extrusive
rock is a
VOLCANIC
rock
A Closer Look at an Igneous Rock
Obsidian is a dark-colored volcanic glass that forms from the very rapid
cooling of molten rock material. It cools so rapidly that crystals do not form.
Is it fine-grained or
coarse-grained?
Is this rock Intrusive or
Extrusive?
http://www.youtube.com/watch?v=P
qgHUPSTojY
Must write down TWO things you
learned!!!!
Be prepared to share!
A little Science Rap
http://www.youtube.com/watch?v=rkGVE6
wNAzo