Erosion
Erosion is not the same as
weathering. Weathering is the
process where rock is broken
down or dissolved into smaller
pieces by physical, chemical or
biological weathering process.
Transport by water:
Everyday, millions of tons of sediments
are moved along rivers, coasts and
deep oceans.
Transport by wind:
Wind transport can result in stunning
landscapes as sand is blown away from
place to place. In the deserts, dunes are
created. Wind can also create sand
storms
Erosion (or mass wasting) involves the movement of the weathered rock (now pebbles, sand or soil) from one place to the other by the action of wind, ice, water and gravity. Examples of mass wasting include rock falls, slumps, and debris flows
Transport makes erosion complete, because it is the part that involves the movement of the eroded materials or sediments.
Transport by water:
Everyday, millions of tonnes of sediments are moved along rivers, coasts and deep oceans. Water transport occurs in four ways: Traction, saltation, fine particles and soluble salts.
Transport by wind:
Wind transport can result in stunning landscapes as sand is blown away from place to place. In the deserts, dunes are created. Wind can also create sand storms
Rocks and the Rock Cycle
Three
Types
of
Rocks
• Rocks are
classified by
how they form
– Igneous
– Sedimentary
– Metamorphic
– Rocks can change
from one type to Schist
another over time
Igneous Rocks
• Igneous rock:
forms when molten
rock (magma) cools
and hardens
• Classified by:
– Where they form
– Crystal (grain) size
Basalt
Intrusive igneous: cooling
takes place slowly beneath
Earth’s surface
granite
Extrusive igneous:
cooling takes place
rapidly on Earth’s
surface
Pumice
Sedimentary Rock
• Sedimentary rock: forms from the
compaction and/or cementation of
sediments
• This process is called lithification
• Sediments are:
– Rock pieces
– Mineral grains
– Shell fragments
Limestone
How do sediments form?
Sediments form
through the
processes of
weathering and
erosion of rocks
exposed at
Earth’s surface
weathering
erosion
Sedimentary Rock can….
• Sedimentary rock can also form from
the chemical depositing of materials
that were once dissolved in water
gypsum
• When water
evaporates,
minerals are
left behind and
form rock
Classtic sedimentary rocks
are those that are formed by
accumulation, compaction, and
cementation of different
solid particles that came
from mechanical or chemical
weathering.
gypsum
gypsum
Conglomerate
gypsum
breccia
gypsum
Sandstone
gypsum
Siltstone
gypsum
Shale
• Metamorphic
Metamorphic Rock
rock: forms when
any rock type is
changed into a
different kind of
rock
• Changes due to
great heat and/or Gneiss
pressure
How does rock change?
• Rocks are heated,
squeezed, folded,
or chemically
changed by
contact with hot
fluids
marble
a. Cementation and compaction (lithification)
b. Heat and pressure
c. Weathering, transportation(erosion), and deposition
d. Cooling and solidification
e. Melting
Rocks/Rock Cycle Foldable
• Your foldable should include the
following:
1. Name of each rock type
2. How each rock type formed
3. A brief description of rock
type
4. At least 2 examples of each
rock type
5. Illustrate 1 example for each
rock type
Copy Me
Do Now – Tuesday March 11
In Textbook:
• Complete
• pg. 107 #1-8
Do Now – Thursday March 4
Rock
Texture
Composition
Comments
Limestone is composed of the mineral
Conglomerat
e
Coarse,
2mm
Rounded pebbles
Rounded pebbles, sand
and clay can easily be
seen
Sandstone
Medium,
.0625 – 2 mm
Quartz, other
minerals and rock
fragments
Sand grains can be
seen; rough surfaces
Shale
Microscopic,
.004 - .06 mm
Clays, micas
Has muddy appearance
Limestone
Coarse to fine
Calcite, shells
May contain fossils,
seashells; fizzes when
in hydrochloric acid
Chert
Fine
Quartz
Is light-colored; also
called flint; once used
for arrowheads
Rock salt
Coarse to fine
Halite
Has salty taste;
table salt
A.
B.
C.
D.
quartz
calcite
halite
gypsum
Based on the information given about each of these rocks,
into which rock type would all these examples be classified?
A.
B.
C.
D.
Igneous
Metamorphic
Sedimentary
Mineral
Moh's
Hardness Scale
Approximate Hardness of
Common Objects
Talc
1
Gypsum
2
Fingernail (2.5)
Calcite
3
Copper penny (3.5)
Fluorite
4
Iron nail (4.5)
Apatite
5
Glass (5.5)
Feldspar
6
Steel file (6.5)
Quartz
7
Streak plate (7.0)
Topaz
Topaz
8
Corundum
9
Gypsum
10
Diamond
Which statement is best
supported by the data
shown?
A. An iron nail contains
fluorite.
B. A streak plate is composed
quartz.
C. Topaz is harder than a
steel file.
D. Apatite is softer than a
copper penny.
Based on the
processes shown in
the diagram, which
type of rock is formed
at #1?
A. Sedimentary
B. Igneous
C. Metamorphic
D. Clastic
Because heat and
pressure are needed to
form #3, it must be what
type of rock?
A.
B.
C.
Sedimentary
Igneous
Metamorphic
Questions:
1. What is a sedimentary rock?
2. What processes must occur to produce
a sedimentary rock?
3. What is a metamorphic rock?
4. What processes must occur to produce
a metamorphic rock?
5. What is an igneous rock?
6. What processes must occur to produce
an igneous rock?
Conclusion: