5 minute check
December 10, 2013
What is the difference between
Intrusive and extrusive igneous rocks?
5.1 - The student will distinguish between sedimentary,
igneous, and metamorphic rocks.E.8.C.1 - Students know
sedimentary rocks and fossils provide evidence for changing
environments and the constancy of geologic processes.
5 minute check
December 11, 2013
What is the difference between Mafic
and Felsic igneous rocks?
5.1 - The student will distinguish between sedimentary,
igneous, and metamorphic rocks.E.8.C.1 - Students know
sedimentary rocks and fossils provide evidence for changing
environments and the constancy of geologic processes.
• Igneous rocks are the
most common rocks on
Earth, but because most of
them exist below the
surface you might not
have seen too many of
them.
• 75% of the rocks exposed
at the surface are
sedimentary rocks.
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
Sediments are loose materials such as rock
fragments, mineral grains, and bits of shell
that have been moved by wind, water, ice, or
gravity.
Sediments come from already-existing rocks
that are weathered and eroded.
Sedimentary rock forms when sediments are
pressed and cemented together, or when
minerals form from solutions.
alreadyexisting rocks
that are
weathered and
eroded
sediments are pressed
and cemented
together, or when
minerals form from
solutions
• Sedimentary rocks often form as layers.
◦ The older layers are on the bottom because they
were deposited first.
◦ Sometimes, forces within Earth overturn layers of
rock, and the oldest are no longer on the bottom.
• Sedimentary rocks can be made of just about any
material found in nature.
◦ Sediments come from weathered and eroded igneous,
metamorphic, and sedimentary rocks.
• Sediments also come from the remains of some
organisms.
◦ The composition of a sedimentary rock depends upon the
composition of the sediments from which it formed.

Sedimentary rocks are classified by their
composition and by the manner in which they
formed.

The three types of sedimentary rocks are
◦ Detrital
◦ Chemical
◦ Organic
sediments are pressed
and cemented
together, or when
minerals form from
solutions
alreadyexisting rocks
that are
weathered and
eroded
Detrital
Chemical
Organic

Detrital sedimentary rocks are made from the
broken fragments of other rocks.

When rock is exposed to air, water, or ice, it
breaks down chemically and mechanically.
• This process, which breaks rocks into smaller
pieces, is called weathering.
• The movement of weathered material is called
erosion.
• Where sediments are deposited, layer upon layer
builds up.
• Pressure from the upper layers pushes down on the
lower layers.
 If the sediments are small, they can stick together
and form solid rock. This process is called
compaction.
If sediments are large, like sand and pebbles,
pressure alone can’t make then stick together
• Large sediments have to be cemented together.
• As water moves through soil and rock, it picks up
materials released from minerals during
weathering.

• The resulting solution of water and dissolved
materials moves through open spaces between
sediments.
Chemical sedimentary rocks
form when dissolved minerals
come out of solution.
• Minerals collect when seas or
lakes evaporate. The deposits
of minerals that come out of
solution form sediments and
rocks.
• Chemical sedimentary rocks
are not made from pieces of
preexisting rocks.

• Large areas of the central United States have
limestone bedrock because seas covered
much of the country for millions of years.
• It is hard to imagine Kansas being covered
by ocean water, but it has happened several
times throughout geological history.
• When water that is rich in dissolved salt
evaporates, it often deposits the mineral halite.
• Halite forms rock salt.
• Rock salt deposits can
range in thickness from
a few meters to more
than 400 m.
• Companies mine these deposits because rock
salt is an important resource.
compaction
sediments are pressed
and cemented
together, or when
minerals form from
solutions
alreadyexisting rocks
that are
weathered and
eroded
Detrital
Chemical
Broken
fragments of
other rocks
Dissolved minerals come
out of solution
cementation
limestone
weathering
erosion
Halite
Organic
• Rocks made of the remains of once-living
things are called organic sedimentary rocks.
• One of the most common organic
sedimentary rocks is fossil-rich limestone.
• Like chemical limestone, fossil-rich
limestone is made of the mineral calcite.
• Fossil-rich limestone mostly contains
remains of once-living ocean organisms.
• Chalk is another
organic sedimentary
rock that is made of
microscopic shells.
• When you write with
naturally occurring
chalk, you’re crushing
and smearing the calcite-shell remains
of once-living ocean organisms.
• Another useful organic sedimentary rock
is coal.
• Coal forms when pieces of dead plants are
buried under other sediments in swamps.
• These plant materials are chemically
changed by microorganisms.
• The resulting sediments are compacted over
millions of years to form coal, an important
source of energy.
sediments are pressed
and cemented
together, or when
minerals form from
solutions
alreadyexisting rocks
that are
weathered and
eroded
compaction
Detrital
Chemical
Broken
fragments of
other rocks
Dissolved minerals come
out of solution
cementation
limestone
weathering
erosion
Halite
Organic
Made of the
remains of
once living
things
chalk
coal
5 minute check
December 12, 2013
What are the 3 types of Sedimentary
rock? And how is each one formed?
5.1 - The student will distinguish between sedimentary,
igneous, and metamorphic rocks.E.8.C.1 - Students know
sedimentary rocks and fossils provide evidence for changing
environments and the constancy of geologic processes.

Sedimentary Rocks

- Detrital-weathering then erosion and then deposition
◦ ◦ ◦ -
Copyright © 2010 Ryan P. Murphy

NO MOVEMENT- the rock does not move, it just
breaks into smaller pieces
◦ There are two kinds:
 Chemical weathering involves a chemical change in at
least some of the minerals within a rock. (rust by carbon
dioxide)
 Physical or Mechanical weathering involves physically
breaking rocks into fragments without changing the
chemical make-up of the minerals within it. For example
weeds growing through or water freezing and breaking
apart the rock, or animals stepping on and breaking.
 Abrasion: rocks worn away by grinding action of other rocks

THE MOST IMPORTANT factor in determining rate
of weathering are
◦ Rock type
◦ climate

A hot and wet climate causes weathering to place
at a much faster rate then in a dry and cool place.

Process where fragments of soil and rock are
broken off from the surface and carried away.
Copyright © 2010 Ryan P. Murphy
Copyright © 2010 Ryan P. Murphy
Copyright © 2010 Ryan P. Murphy
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Process by which fragments of rock are deposited
in a new location.
Copyright © 2010 Ryan P. Murphy

Deposition: Process by which fragments of
rock are deposited in a new location.
Copyright © 2010 Ryan P. Murphy

Deposition: Process by which fragments of
rock are deposited in a new location.
Copyright © 2010 Ryan P. Murphy

Deposition: Process by which fragments of
rock are deposited in a new location.
Copyright © 2010 Ryan P. Murphy

Caused by weathering,
Copyright © 2010 Ryan P. Murphy

Caused by weathering, erosion,
Copyright © 2010 Ryan P. Murphy

Caused by weathering, erosion, and
deposition.
Copyright © 2010 Ryan P. Murphy

Sediment can be transported by wind and
water.
Copyright © 2010 Ryan P. Murphy

Picture of sediment deposition of the
Amazon Delta from space.
Copyright © 2010 Ryan P. Murphy

Sedimentary Rocks

-
Detrital- Sediments are compacted and cemented together.
 Caused by weathering, erosion, and deposition.

-
Chemical – dissolved minerals come out of solutions.
 Limestone and Halite
◦ -
Copyright © 2010 Ryan P. Murphy
Gravel
Conglomerate

Sedimentary Rocks

-
Detrital- Sediments are compacted and cemented together.
 Caused by weathering, erosion, and deposition.

-
Chemical – dissolved minerals come out of solutions.
 Limestone and Halite

-
Organic – Made of the remains of once living things
 Chalk and coal
Copyright © 2010 Ryan P. Murphy

Sedimentary Rocks are usually layered.
Copyright © 2010 Ryan P. Murphy
Usually horizontal

Layers can be from old living materials
(fossils).
Copyright © 2010 Ryan P. Murphy
5 minute check
December 13, 2013
5.1 - The student will distinguish between sedimentary, igneous, and
metamorphic rocks.E.8.C.1 - Students know sedimentary rocks and fossils
provide evidence for changing environments and the constancy of geologic
processes.
How a little bit of heat & pressure transform
rocks!
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
The term "metamorphic"
means "to change form."
Any rock (igneous,
sedimentary, or metamorphic)
can become a metamorphic
rock. If rocks are buried deep
in the Earth at high
temperatures and pressures,
they form new minerals and
textures all without melting. If
melting occurs, magma is
formed, starting the rock
cycle all over again.
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
There are two types
of metamorphic
rocks.
Each is classified
according to its
composition and
texture.
◦ Foliated
◦ Nonfoliated.
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
FOLIATED metamorphic
rocks are those in which
the minerals have been
flattened and pushed
down into parallel layers.
The bands in foliated
metamorphic rock look
like pages in a book.
Examples of foliated rocks
are slate, shale, and
gneiss.

NON-FOLIATED metamorphic rocks do
not display layers. Rather, they are
massive structures with no obvious
banding. The mineral grains grow
and rearrange, but they don’t
form layers.
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

A good example of non-foliated rock
is quartzite, the smooth-textured,
metamorphosed form of the mineral
quartz.
A coarse-textured non-foliated rock is
marble.
Anthracite, or hard coal, is a nonfoliated rock that forms when intense
pressure drives gases out of soft coal,
causing it to harden.

Physical Properties of Minerals and Rocks
1. luster – how light reflects off of it
 Matalic-Shiny
 Non matalic – not shinny, dull, pearly, glassy
2. Streak – Powdered line left behind from a mineral
3. Hardness – Scratching the mineral with different items.
 Mohs scale- 1-softest – 10 hardest
4. How the mineral breaks
 Cleavage – flat and smooth
 Fracture – very jagged