Download Igneous Rocks

Colleen Fadden
Renee Pollard
Andrea Popolizio
 Igneous
rocks are the oldest type of
rocks.
 Deep
inside the earth where it is very
hot, there is melted rock called magma.
 As
the magma comes up to the surface, it
starts to cool and turns into solid igneous
rock.

All igneous rocks do not cool the same way, that
is why they do not look all the same.

Depending on how the rocks cool, they are
classified as either intrusive or extrusive.
•
Intrusive igneous rock is formed when the magma
cools slowly deep under the earths surface, causing
large crystals
•
Extrusive igneous rock is formed when the magma
comes from the volcano and reaches the earth’s surface
through big cracks. The lava cools fast cause small
crystals.
 Normally
contains no fossils
 Rarely reacts with acid
 Usually have no layering
 Usually made of two or more minerals
 May be light or dark colored
 Usually made of mineral crystals of
different sizes
 Sometimes have openings or glass fibers
 May be fine-grained or glassy (extrusive)
Granite
Pumice
Obsidian
Pegmitatite
 Sedimentary
rocks are rocks that are
formed by sediments from the earth
pressed together. This usually occurs
underwater.
 Sediments
are small pieces of rocks.
 Sedimentary
rocks are formed by broken
pieces of rocks that pile up.
 When
the sediments pile up they form
layers.
 Over
a long period of time, the pieces
pile up and get pressed together to for
rocks.
 Contain
fossils most of the time
 React with acid
 Have layers
 Made up of pieces cemented of pressed
together
 Contain a variety of colors
 Particle sizes are sometimes different
Examples of Sedimentary Rocks
Sandstone
Shale
Limestone
Coal
 Metamorphic
rocks are rocks that have
been changed.
 They
are formed deep within the Earth.
 Metamorphic
rocks were once igneous
and sedimentary rocks.
 They
are the least common of the three
types of rocks.
 Metamorphic
rocks are formed when
heat and pressure are applied to
sedimentary and igneous rocks.
 The
heat and pressure cooks the rocks
and changes their structure.
 The
chemical changes that take place are
what makes the appearance of rocks very
different.
 To
demonstrate how metamorphic rocks
are formed, try this:
• Squeeze you hands together very hard. You will
begin to feel heat and pressure. When the
Earth’s crust moves, the heat and pressure cause
the rocks to squeeze together so hard that the
rocks change shapes.
 There
are two types of metamorphic
rocks: foliated and non-foliated.
 Foliated
metamorphic rocks have layers,
or banding.

Examples of foliated metamorphic rocks are:
• Slate
• Schist
• Gneiss
 Non-Foliated
 Examples
• Marble
• Quartzite
Rocks are not layered
of non-foliated rocks are:
Marble
Quartize
Gneiss
Marble
Now
it’s time to use what you
have learned for an activity!
Today you will explore some
rocks. You’ll sort the rocks and
discuss them with your partner.
See what new things you can
discover!
 Science
notebook
 The Observing Rocks Worksheet
 1 hand lens
 1 magnet
 1 set of 12 rocks
 1 cardboard tray
 Yourself
1.


Think about your senses.
How many senses do you have?
What information do you get from using
each one?
2. Explore the 12 rocks in front of you using all
of your senses except taste. Describe to
your partner what you see/feel/smell.
Write the answers to the following
descriptors in each of the small boxes about
each numbered rock.
 What is its color?
 Is it magnetic?
 Does it have any fossils?
3. Next, sort the rocks any way you choose.
Think about why you sorted them that
way. Share with your partner. Write
down the way you sorted them in Box 2 of
your worksheet.
4. Discuss with your partner the reasons
you grouped your rocks how you did.
Can they be sorted another way? Put the
rocks back in the middle and find
another way to separate them. Write
down the second way you separated the
rocks in Box 3 on the worksheet.
5. Review how you separated the rocks.
Write down the properties/ the ways you
described and separated the rocks on
the lines at the bottom of your paper.
 Here
are two links to lessons/activities
about rocks
 http://www.bbc.co.uk/schools/scienceclips
/ages/7_8/rocks_soils.shtml - This website
allows you to virtually test different
properties of rocks.
 http://www.gamequarium.org/cgi-
bin/search/linfo.cgi?id=9686 – This is a link
to a Magic School Bus episode about rocks
and erosion.
 Here
are two links to lessons/activities
about rocks
 http://www.bbc.co.uk/schools/scienceclips
/ages/7_8/rocks_soils.shtml - This website
allows you to virtually test different
properties of rocks.
 http://www.gamequarium.org/cgi-
bin/search/linfo.cgi?id=9686 – This is a link
to a Magic School Bus episode about rocks
and erosion.
 http://library.thinkquest.org/J002289/roc
ks.html#
 http://www.kidsgeo.com/geology-forkids/0028-metamorphic-rocks.php
 http://www.rocksforkids.com/RFK/howro
cks.html#Metamorphic
 http://www.historyforkids.org/sciencefor
kids/geology/rocks/metamorphic/