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Planet Earth
Ms. Lyons
Minerals

Rock is made up of one or more pure, naturally
occurring, non-living, crystal like materials call
minerals.
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Most minerals are quite rare. Only a few, such as
quartz, feldspar and mica, are found throughout
the Earth’s crust (the thin outermost layer of
Earth)
Minerals Continued…
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A mineral can be an element (a pure substance)
or a compound (two or more elements
combined)
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Example: Quartz is a compound of silicon and
oxygen
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The Mohs Hardness Scale was developed to
identify minerals according to how hard they are.
A mineral that is rated 1 is very soft and a
mineral that is rated 10 is very hard. (Gold is a
10- the hardest mineral)
Crystals

Crystals are the building blocks of
minerals. A mineral’s crystals are used to
help people identify it.

You can identify crystals using the Six
Major Crystal Systems
Six Major Crystal Systems
Other Clues for Mineral Identification
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Lustre – The ‘shininess’ of the mineral
Colour – The colour of the mineral can be used
to identify it. However a mineral will be a
different colour if it is pure vs. if it is not.
Streak – Is the colour of the powdered form of
the mineral (this is a good way to identify fake
gold)
Cleavage and Fracture – The way a mineral
breaks apart can be a clue to its identity. If it
breaks along smooth, flat surfaces, it is said to
have cleavage. If it breaks with rough or jagged
edges it is said to fracture.
Rock Families

Scientists have grouped Rocks into three
major families, or types, based on how
they form.
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The three families are igneous,
sedimentary and metamorphic rocks.

Each can generally be identified by its
appearance.
Igneous Rock
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Igneous rock forms when hot magma or lava
cools and solidifies.
Magma is melted rock found beneath the
Earth’s crust where temperatures are high.
When magma cools and hardens below the
Earth’s surface it is called intrusive rock.
When magma breaks through the Earth’s surface
in a volcanic eruption, it is called lava.
Rock that forms when lava cools is called
extrusive rock.
Igneous Rock
Sedimentary Rock

Sedimentary Rock makes up about 75% of all
rocks that we see on Earth. This kind of rock is
made from sediments.

Sediments are loose materials, such as bits of
rock, minerals, and plant and animal remains
that get packed in layers and cemented together.

The arrangement of these layers is called
stratification.
Sedimentary Rock…

The process of squeezing the layers together is
called compaction.

In some rocks, minerals dissolve as water soaks
into the rock, forming a natural cement that
sticks pieces of sediment together (this is called
cementation)
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Examples?
Sedimentary Rock

Shale
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Sandstone
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Conglomerate
Metamorphic Rock
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Metamorphic Rock means ‘changed form’. This
type of rock may be formed below the Earth’s
surface when extremely high pressures and heat
cause the original rock or parent rock to change
form.
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The type of rock formed depends on the amount
of pressure applied.
Metamorphic rock can change so completely that
it no longer looks like the parent rock. There are
enough common characteristics , however that
geologists know they are related.
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Metamorphic Rock

For example limestone and marble look different,
but they both have a hardness value of 3, and
both are made of the mineral calcite. Both
limestone and marble react with dilute
hydrochloric acid.
The Rock Cycle
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The Rock Cycle – Rocks continue to
change in an ongoing process. Rocks
change as a result of the rock cycle. In
order to identify rocks after they have
weathered, you need to identify the
minerals found within the rock.
The Rock Cycle
Rock Cycle
Sediment and Soil
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Soil is formed from the combination of compost
(which is decaying plant matter), rock,
sediments, living material like twigs and leaves
and dead worms or insects.
The dark coloured portion of the soil is called
humus and is very fertile.
Soil Continued…
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Layers of soil make up a soil profile.
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The top layer is called topsoil (it consists of
humus and small grains of rock)
The second layer is lighter in colour, and contains
less humus and larger rock chunks.
The third layer contains ever larger rocks that are
only beginning the process of being broken down
into soil.
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Soil Profile
Erosion and the Moving Crust
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Erosion is the movement of rock and
mineral grains from one place to another.
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Sediment comes from larger rocks that
have broken down or worn away through
weathering.
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Sedimentation is the process where
eroded material is deposited and built up.
Mechanical Weathering
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Mechanical Weathering is the physical breakup or disintegration to rocks.
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For example, gravity causes rocks to fall down a
cliff and break apart.
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Rocks rolling down a slope or in a fast-moving
stream rub and bump against each other,
becoming smoother and more rounded.
Frost Wedging
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Frost wedging – during the daytime in
the spring water runs into cracks in rocks.
Then at night the water freezes in the
cracks and pushes the rocks apart. Each
day more water runs into these cracks
until eventually the rock breaks apart.
Mechanical Weathering
Chemical Weathering
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Chemical Weathering breaks down minerals
through chemical reactions
Some material may be dissolved, other materials
are weakened. Rocks react with water, with other
chemicals dissolved in water, or with gases in the
air.
An example of chemical weathering is acid rain,
which contains dissolved chemicals from air
pollution. Acidic rain reacts with some rocks such
as limestone. The rock material dissolves easily
in the water and washes away.
Chemical Weathering
Biological Weathering
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Biological Weathering is the physical or
chemical breakdown of rock caused by living
organisms, such as plants, animals, bacteria and
fungi.
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Physical Biological Weathering occurs, for
example, when a plant root wedges into a rock
by forcing its way into a crack. As the root grows
and expands, so does the crack, and the rock is
pushed apart until it eventually crumbles and
breaks.
Biological Weathering
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Biological Weathering can also be chemical. For
example acidic fluids produced by plant roots,
bacteria, fungi and some insects and small animals
can cause chemical reactions. As the rock slowly
dissolves and flows away with rainwater, cracks and
crevices increase in size until the rock finally breaks
apart.
Erosion
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Mechanical, Chemical and Biological weathering
work together constantly to change our
landscape.

Glaciers, gravity, wind and water all cause
erosion. Changes in our earth’s surface that
happen slowly (those caused by glaciers) are
called “gradual changes”. Those that happen
quickly like floods, landslides and rockslides are
called “sudden changes”.
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Water in motion is a very powerful cause of
erosion
Weathering and Erosion
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http://www.teachertube.com/viewVideo.p
hp?video_id=20814&title=Weathering_an
d_Erosion_by_StudyJams
The Moving Crust
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The earth’s crust is the layer of the earth that
we walk on and build our homes on. It also
includes deeper areas where minerals and oil and
gas are mined.
The mantle is found under the crust. It is made
of rock material.
The upper mantle is solid and the lower mantle
has the consistency of taffy.
The earth’s crust and the upper mantle form the
lithosphere.
Continued…
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The outer core is under the mantle and
consists of iron and nickel. The
temperature here is 5500 degrees Celsius
and is so hot that iron and nickel are in a
liquid state.
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The intense pressure of all the layers
forces the inner core to have a
temperature of over 6000 degrees Celsius.
Layers of the Earth
Continued…
Layers of Our World
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http://www.teachertube.com/viewVideo.p
hp?video_id=43078&title=Layers_of_Our_
World
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Geographic Information System
Continental Drift
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Continental drift is the belief that the
continents at one time where completely joined
together and over the years have drifted apart.
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A German scientist named Alfred Wegener found
evidence that supported his theory. This evidence
came in the form of rock similarities, fossil
similarities, and climatic similarities between
continents. Wegener believed that all of the
earth’s continents had been joined together in a
giant supercontinent called “Pangaea". He had
difficulty proving this theory and died in 1930 still
trying to prove it.
Advances in Technology
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Sonar (sound wave technology) revealed
to scientists that the ocean’s floor is not
flat. It revealed that mountain ranges
exist on the ocean floor.
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What was causing the mountains to form?
Sea Floor Spreading
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Sea floor spreading is the process in which
an ocean floor slowly increases in size over
time because of the formation of new igneous
rock along a fault.
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The ocean floor is spreading and getting
wider by about 2cm per year (about the same
speed at which your fingernails grow).
Sea Floor Spreading
Continued
Theory of Plate Tectonics
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Theory of plate tectonics states that the
earth’s crust is broken up into pieces called
plates.
These plates are always moving on the earth’s
mantle.
Plates that are moving together are called
converging plates and plates that are pulling
apart are called diverging plates.
One explanation for why plates move is based on
the theory that a convection current is causing
the earth’s plates to move.
Convection Currents
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Geologists are still not sure what causes
the Earth’s plates to move. One
explanation is that convection currents in
the mantle under the Earth’s crust move
the plates.

A convection current is the flow
resulting from the rise of warmer
materials and the sinking of cooler
materials.
Convection Currents Continued…
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When two plates collide or converge, one is
shoved under the other. These places are called
subduction zones.

Scientists suggest that subduction zones form
where convection currents cool and sink.
At the upper part of the mantle, the heated rock
moves the plate along as if it were on a conveyer
belt. When the rock cools, it sinks down into the
mantle pulling the plate with it, forming an ocean
trench.
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…
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If there is Sea Floor Spreading does that
mean the Earth’s crust is getting bigger??
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The theory of plate tectonics is our best
explanation for the formation of
earthquakes, volcanoes, and mountains.
Earthquakes
Why do they Happen?
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Earthquakes are usually caused when rock
underground suddenly breaks along a fault.
This sudden release of energy causes the seismic
waves that make the ground shake.
When two blocks of rock or two plates are
rubbing against each other, they stick a little.
They don't just slide smoothly; the rocks catch
on each other. The rocks are still pushing against
each other, but not moving. After a while, the
rocks break because of all the pressure that's
built up. When the rocks break, the earthquake
occurs.
How do we measure Earthquakes?
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Scientists use a machine called a seismograph
to measure earthquakes.
This machine is attached to bedrock (the solid
rock that lies beneath the soil and looser rocks)
in order to feel vibrations that result from an
earthquake
Continued…
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Seismologists (scientists who study
earthquakes) use a method of
measurement called the Richter Scale to
describe the strength of the earthquake.
The smaller the number the less
devastating the quake.
Most earthquakes that cause damage and
loss of life register between 6 and 8 on the
Richter Scale.
Earthquake Waves
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There can be many episodes of groundshaking movement in an earthquake
caused by seismic waves.
Seismic waves are the energy waves
that travel outward from the source of the
earthquake.
Aftershocks are smaller quakes that
happen after the initial quake.
Aftershock Damage
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Aftershocks can cause damaged buildings
to collapse. The Kobe earthquake in
Japan, 1995, produced over 600
aftershocks.
Types of Earthquake Waves
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There are 3 kinds of seismic waves that
occur in an earthquake.
1) Primary or P waves
2) Secondary or S waves
3) Surface waves
Primary or P Waves
Primary (P waves) travel the fastest of
all three types of waves and can pass
through solids, liquids and gases.
 These cause slight vibrations that rattle
dishes and warn people that an
earthquake is taking place and that larger
earth movement may be on its way.
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Secondary or S Waves
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Secondary (S waves) travel more
slowly than P waves and can only pass
through solids.
Surface Waves
Surface waves are the slowest of the
three waves, but their rolling motion
causes the most damage.
 They break up roads and buildings,
because they cause one part of a structure
to move up while the other part moves
down.
 These waves travel outward like the
ripples in a pond when you throw a
pebble.
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What does the Seismograph tell you?
What can this tell us?
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The earthquake that happened in Japan
registered on the seismograph at the University
of Manitoba.
This is because P waves travel right through the
centre of the Earth. S waves did not register.
Because we know S waves cannot travel through
liquid but P waves can, we can hypothesize that
the Earth’s outer core is liquid.
Locating an Earthquake

How do you estimate how far away a
thunderstorm is? The same theory applies
to earthquakes.
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P waves travel faster than S waves.
Therefore the further apart the P and S
waves are, the farther away the
earthquake.
Source of the Earthquake
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Scientists have a special name for the source of
an earthquake. In fact, they use two names.
The place deep in the crust where the earthquake
begins is called the focus of the earthquake.
The primary and secondary waves come from the
focus of the earthquake.
The surface location directly above the focus is
called the epicentre.
Surface waves travel out from the epicentre.
Types of Rock Movement in
Earthquakes
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The rock in the Earth’s crust is under pressure all
the time from tremendous forces. These stresses
can cause rock to bend and stretch. But when the
pressure is too great, the rock breaks suddenly,
creating a fault.
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Movement along a fault can spread more than a
kilometer in a second.
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Fault zones exist where tectonic plates meet.
Normal Faults
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Normal faults occur because of tension forces (rock being
pulled apart). In this type of fault, rock generally moves
down.
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These generally happen on the sea floor and cause little
damage
Reverse Faults
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Reverse faults occur because of compression
forces (rock being pushed together). In this fault,
rock generally is forced upward.
Strike-Slip or Transform Faults
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Strike-slip or Transform faults occur because
of shear forces. Rock along the edges of these
faults generally have many bumps and bulges.
Other Effects of Earthquakes
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Some earthquakes happen under the sea.
The water displaced by an earthquake can
become a huge wave called a tsunamis.
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Tsunamis can travel across oceans and
cause great damage when they break on
shore.
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In mountains, earthquakes can trigger
avalanches or rock slides.
Volcanoes
Volcanoes
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A volcano is an opening in the Earth’s
crust that releases lava, steam, and ash
when it erupts (becomes active).
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The openings in the earth’s crust when a
volcano erupts are called vents. When
volcanoes are not active, they are
described as dormant.
How are Volcanoes Formed?
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Volcanoes are formed when rock surfaces
beneath the earth’s surface push against each
other.
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The rock pushing downwards begins to melt and
turn into magma.
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Eventually there is so much magma that it is
forced up through cracks in the earth’s crust and
an eruption occurs.
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Volcanoes erupt in stages over a period of weeks,
months, or even years.
Famous Volcanoes
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Mount St. Helens (U.S.A.) erupted in
1980.
Famous Volcanoes
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Mount Vesuvius in Italy has been dormant since
1944 and scientists believe that it is set to erupt
any time.
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A huge area beneath the peak is filling with
magma. The situation is even more dangerous
because the opening at the peak is sealed by a
rock ‘plug’. Plans are being made for emergency
measures if such an event occurs.
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Mount Vesuvius erupted in 79 BC. Many things,
including people were preserved in the ash.
Mt. Vesuvius
Ring of Fire
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The volcanoes around the Pacific Ocean
make up the Ring of Fire.
The name comes from the circle of
volcanoes that pour red hot lava, fire and
steam.
 Most volcanoes in the Ring of Fire occur at
subduction zones.
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Ring of Fire
Mountains
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Mountain building takes many years, and it
creates some of the most beautiful scenery in
the world!
How are Mountains Formed?
Most mountains are large areas that have
been uplifted due to the movement or
heating of plates.
 The movement along these boundaries
can create great heat and pressure. The
pressure can cause the rocks to fold and
fault, creating mountains!
 Sometimes the heat can melt the rock and
cause it to form volcanoes.

Continued…
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Sedimentary rocks that are places under
slow, gradual pressure can either fold or
break.
Rock that has been heated and is soft begins
to fold.
The top part of this folded rock is called the
anticline, and the bottom of the fold is called
the syncline
Continued…
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If the rock is too brittle to fold, it can break,
forming a fault. Faults can be the result of
squeezing the earth’s crust or of stretching the
earth’s crust.
When the earth’s crust is squeezed together,
sedimentary rock forms into slabs that move up
over each other like shingles on a roof. This
process is called thrust faulting.
When the earth’s crust is stretched blocks of rock
can tilt and slide down. Here, older rocks may
end up on top of younger rock, and these huge
amounts of rocks can form mountains called
fault block mountains.
Fault Block Mountain
The Rockies
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The Canadian Rockies have been formed
by sedimentary rock sliding on the
basement rock and pushing the crust
upwards (Sedimentary rock is seen at the
surface).
Continued…
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The American Rockies have been formed
by igneous and metamorphic (basement
rock) rock being shoved on top of each
other and pushed upwards (Basement
rock is seen at the surface).
Age of a Mountain
Young mountains are jagged at the top.
 Older mountains are more rounded
because their surfaces have been eroded
and weathered due to mechanical,
biological and chemical weathering
 The Canadian Rockies are fairly young, the
Laurentian Mountains in Quebec are older
and are in the process of being worn
down.

Fossils
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Fossils provide clues about when life
began, and when plants and animals first
lived on the land.
How are Fossils Formed?
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A fossil is formed when soft parts of a dead
animal (skin, muscles and organs) decay quickly,
but the hard parts of the animal (teeth, bones
and shells) are altered and then fossilized.
Bones of the animal become petrified or turned
into a rock like substance.
This happens when water penetrates the bones of
the dead animal and dissolves the calcium
carbonate in the bone. Then a very hard mineral
(silica) is deposited and left behind. This mineral
turns the bones into a rock like substance.
Types of Fossils

Sometimes the actual organism or parts of it may be
preserved as a fossil. These are called original remains
(ex. fly’s preserved in resin, dinosaurs preserved in tar pits
and woolly mammoths preserved in ice.)

Trace fossils are evidence of animal activity (ex.
Footprints, or worm holes that have become fossilized).

A mould is a type of fossil, in which the hard parts of the
organism have dissolved, leaving a cavity in the rock.

A cast is a type of fossil in which sediments or minerals
have filled a mould and hardened into rock.
Fossil Mould and Cast Formation
Geologic Time
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Principle of superposition states that in
undisturbed layers of sedimentary rock, the
oldest layers are always on the bottom and the
youngest layers are always on the top.
Strata is layers of sedimentary rock.
Relative dating is a strategy that scientists use
to figure out the age of the rocks according to
their position in the strata.
Index fossil – a type of fossil that can be used
to determine the age of the material in which it is
found.
Clues From Technology
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The amount of certain elements in a rock can tell geologists
a great deal about the rock’s age. Over billions of years
some elements can change into others.
Over a period of 4.5 billion years, half of the uranium in a
rock will turn to lead. This is known as the half-life of
uranium.
The half-life of a substance is the amount of time that a
given amount of a radioactive substance takes to be
reduced by one-half.
Radiometric dating is the process of determining the age
of a rock specimen by measuring the amounts of
radioactive particles that are present in the rock and by
knowing the half life of the parent rock.
Geological Time Scale

The geological time scale is a division of Earth’s history into
smaller units based on the appearances of different life
forms
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Precambrian period – was the first 4 billion years that
the earth existed until 590 million years ago (during this
time the first super continent called Rodinia was formed)
Paleozoic Era means ancient life (approximately from 590
million years ago to 248 million years ago)
Mesozoic Era means middle life (approximately from 248
million years ago to 65 million years ago)
Cenozoic Era means recent life (approximately from 65
million years ago to present day)
It is believed that the second super continent Pangea first
split into a northern portion called Laurasia and a southern
portion called Gondwanaland.
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Fossil Fuels
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Petroleum is a type of oil found in rock formations in the
Earth’s crust. It is refined into products such as gasoline or
jet fuel (it is most often found in sedimentary rock).
Fossil Fuels are fuels made of decomposed plants and
other organisms that have been hardened and fossilized.
Fossil fuels take millions of years to develop; examples of
fossil fuels include oil, natural gas and coal.
Bitumen is a heavy almost solid form of petroleum. Some
bitumen deposits are found near the surface of the Earth
and can be mined or heated and pumped to the surface (to
be used as gasoline and or jet fuel).
How Do You Find Oil and Gas?
Scientists study surface rocks and samples
from deep within the ground to identify
traps where oil and gas have accumulated
within rock formations.
 Oil and natural gas can move long
distances through strata and sometimes
escape at the surface. Sometimes the
lighter compounds are removed by the air
or water, leaving heavier types of oil
behind.

Oil and Faults