Download Weathering is the process by which natural forces break down rocks

• Weathering is the process by
which natural forces break down
rocks.
• There are 2 types of weathering:
– Mechanical weathering
– Chemical weathering
1. Making connections with past
learning
We talked about weathering when talking about the
rock cycle.
Weathering is the process by which natural forces
break down rocks.
On ISN 66 Explain, using full sentences and IQIA, how
weathering is connected to the rock cycle. Make sure
to include which type of rock is directly involved
1. Making connections with past
learning
On ISN 66 Explain, using full sentences and
IQIA, how weathering is connected to the
rock cycle. Make sure to include which type
of rock is directly involved
Weathering creates sediment which is
compacted and cemented together to
create sedimentary rock.
• Mechanical weathering is the
breaking up of rocks by physical
forces.
• There are 4 main types:
–
–
–
–
Ice wedging
Exfoliation
Plant root growth
Abrasion
When water freezes, it
expands. Water freezes
in the cracks and pores
of rocks and the force
of its expansion is
strong enough to split
the rocks apart.
The process in which layers or sheets of rock
gradually break off due to the expansion of the rock
caused by a decrease in pressure.
Trees, bushes, and
other plants may
take root in cracks
of rocks. As the
roots of these
plants grow, they
wedge open the
cracks.
The process of
wearing down by
friction, the rubbing
of one object or
surface against
another.
2. Making connections with outside of
the classroom
Have you ever put a beverage in a can into the
freezer and left it? What happens?
On ISN 66, Explain how this example is
connected to ice wedging. Use full sentences,
IQIA.
2. Making connections with outside of
the classroom
Have you ever put a beverage in a can into the freezer
and left it? What happens?
On ISN 66, Explain how this example is connected to ice
wedging. Use full sentences, IQIA.
A can left in the freezer will expand and eventually
explode. This is related to ice wedging because the liquid
in the can is like the liquid that is in the cracks of rocks.
When the liquid freezes, it expands, forcing anything in
the way (the can or the rock) to move or break
3. Make connections outside of the
classroom
I just bought a face wash that claims to exfoliate
my face so I end up with smooth skin.
On ISN 66, explain how mechanical weathering
exfoliation and the exfoliation of my face are
similar.
3. Make connections outside of the
classroom
I just bought a face wash that claims to exfoliate
my face so I end up with smooth skin.
On ISN 66, explain how mechanical weathering
exfoliation and the exfoliation of my face are
similar.
Both exfoliations take layers (of skin or of rock)
off of a surface
4. Make connections outside of the
classroom
On ISN 66 Explain what
is happening in this
picture. Be sure to use
full sentences, IQIA.
Include any vocabulary
terms we have
discusses thus far.
4. Make connections outside of the
classroom
On ISN 66 Explain what is
happening in this
picture. Be sure to use
full sentences, IQIA.
Include any vocabulary
terms we have discusses
thus far.
The plant root growth is
forcing the sidewalk up
and out of the way
resulting in cracking
5. Making connections outside of the
Classroom
This is sandpaper.
Sandpaper is used to make
wood smooth, especially
before painting or staining.
On ISN 66, Explain how this
is connected to the
abrasion example
5. Making connections outside of the
Classroom
This is sandpaper.
Sandpaper is used to make wood
smooth, especially before
painting or staining.
On ISN 66, Explain how this is
connected to the abrasion
example
Sandpaper uses friction to wear
down the surface of wood just
like mechanical weathering
abrasion is when rocks are worn
down at their surface by friction
• The breakdown of rocks by
chemical reactions that change the
rocks’ makeup, or composition.
• There are 2 main types:
– Dissolving
– Rusting
6. Making connections with prior
knowledge
On ISN 66, explain what you know about
chemical reactions. How do you think
chemical reactions can break down rock?
• Water is the main cause
of chemical weathering.
• Many more minerals
dissolve in water that is
slightly acidic – like
lemonade.
•
•
The oxygen in air is
also involved in
chemical weathering.
Many common
minerals contain iron.
When these minerals
dissolve in water,
oxygen in the air and
the water combines
to produce rust.
8. Making connection outside of the
classroom
On ISN 66 explain what
happened to this bike
(why is it that
orange/brown/red
color?)
What do you think will
eventually happen to
the chain?
7. Making connections outside the
classroom
Imagine you had a sugar cube.
If that were to represent a rock, explain in
detail how you could use that to
demonstrate chemical weathering. Write
out the explanation in full sentences, IQIA,
on ISN 66