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Geology Day - Erosion and weathering, Rock Detectives, Volcanoes earthquakes and tsunamis

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Geology
Lesson 1 – Erosion and Weathering
Lesson 2 – Rock Investigations
Mrs Breward
Monday, 10 May 2021
DO NOW TASK: Rock cycle quiz
TASK- Complete the following quiz in your book.
Get ready to self-assess with RED and PURPLE pens.
1. Does the rock cycle ever stop?
2. What are the 3 categories of rock?
Geology- the
study of rocks.
No
Sedimentary, Igneous, Metamorphic
3. Could a rock go from sedimentary rock to metamorphic rock?
Yes
4. Could a metamorphic rock became an igneous rock?
Yes
5. Could a rock go through the entire cycle in our lifetime?
No
6. Does geology move quickly or slowly compared to our lives?
Slowly
What is the same?
What is different?
Did one cause the other?
Justify your answer.
Erosion and weathering
Tuesday, 22 February 2022
Learning objectives
Grade 3/4 – Recall how rocks can be damaged over time.
Grade 5/6 – Explain why some rocks are more affected by
weathering than others.
Grade 7/8 – Predict how much rocks will be affected by
weathering in a given situation.
Rock cycle recap
The Earth, and Rocks are always changing… very simply, this
is how it works:
Sedimentary rock
Igneous rock
Metamorphic rock
Three types of rocks
RECAP.
Sedimentary rock:
Formed by sediment settling over
time (e.g. bottom of ocean)
Metamorphic rock:
Formed from other rocks that have
been changed due to heat and
pressure
Igneous rock:
Formed when magma (molten rock)
cools and hardens
EXTENSION- What do you think the Rock cycle is so
far? Write a definition in your books.
https://youtu.be/SuNfbEDMOQs
1. What are the 3 types of
rock? (1)
2. Describe how fossils are
formed in sedimentary
rocks. (3)
3. Explain how marble is
formed from limestone (2)
Answers
1. Igneous, sedimentary and metamorphic.
2. An explanation linking three of the following points:
• dead animals / plants (1)
• (dead animals / plants) become covered in sediment (1) (Allow covered in sand /
rock / limestone)
• are {squashed / crushed /compacted / pressured} (as layers of sediment build up
on top of one another) (1)
• long time period (1)
• fossils are caused by skeletons/bones / shells / remains (1)
Answers!
3. An explanation linking the following points:
(limestone is subject to)
• heat(1)
• and pressure (1)
(from the surrounding earth)
Ignore melting / magma / lava
Ignore crushed
Freeze-Thaw
Exfoliation
https://yout
u.be/qGw1y
B10lX0
Weathering
Biological
Chemical
Weathering and erosion
What is the difference between weathering and erosion?
Weathering BREAKS down the rock into sediment,
erosion MOVES the sediment to new places
Explaining weathering
Read the steps that cause each type of weathering.
Put them into the correct order.
Explaining weathering
Put the steps into the correct order
Freeze-thaw
Exfoliation
1 Water gets into crack
1 Rock heated by sun and expands
2 Water freezes and expands
2 Rock cools down and contracts
3 Crack is opened up
3 Rock weakened
4 Rock falls to pieces
4 Surface layers of rock peel off
Biological weathering
Chemical weathering
1 Seeds fall into crack
1 Rainwater contains weak acid
2 Crack provides moisture and shelter
2 Acid attacks rock
3 Roots grow
3 Rock dissolved or weakened
4 Crack widens and rock breaks up
4 Rock worn away or broken up
Questions
1) Why are roads in Canada most likely to be affected by freezethaw weathering?
2) Why would a patio be likely to suffer from biological
weathering?
3) Why has the Great Sphynx of Egypt suffered from exfoliation?
Lesson 2: Becoming a rock detective…
https://youtu.be/R5Qz2Zil3dQ
Learning objectives
Grade 3/4 – Identify some types of rock from samples
Grade 5/6 – Evaluate rock structure to determine its type
Grade 7/8 – Explain the characteristics of different rock types
Crystal structures
• Think about the mineral salt.
• It is made of cube- shaped crystals.
• No matter where you find it, on your table or at the beach,
its crystals will be shaped like cubes.
• Use your hand lens to study the rock salt.
The same mineral can have different colours. This is caused by small amounts of different
elements that got into the mineral when it was forming. While the colour of a mineral may vary,
its crystal shape is always the same. For example, diamonds can be clear, yellow, pink, and even
blue, but its crystals will always have eight faces (sides).
Rock structure
Become a geologist
• Measure and weigh your rock sample
• Identify each sample as either sedimentary,
metamorphic or igneous.
• Study the structure of grains and crystals,
can you see any shapes?
• Does the rock feel smooth or rough?
• Record your observations
Metamorphic
Sandstone
Marble
pressure
schist
heat
sedimentary
igneous
limestone
magma
sedimentary
igneous
etamorphic
heat
schist
chist
imestone
marble
magma
pressure
Session 2
Volcanoes, earthquakes and tsunamis
DO NOW TASK
The properties of Igneous Rocks.
• Igneous Rocks are very strong and do not erode (wear
away) easily. Most mountains are made of Igneous
Rock.
• They are strong because they contain crystals.
• These crystals also make them non-porous. This means
that there are no holes in the rock surface and water
(or other liquids) will not soak into it.
Volcanoes
What’s the difference between magma and lava?
Igneous rocks form from the solidification of once-molten rock material.
When this mushy melt is found underground penetrating other rocks, it's called magma, and the
solidified rock is termed intrusive.
By contrast, molten material that has erupted onto the Earth's surface is named lava, which
cools into what geologists call extrusive (or volcanic) rocks.
What type of Igneous Rock will
form at A?
A
Intrusive Igneous
Rock
What type of Igneous Rock will
form at B?
B
Extrusive Igneous
Rock
Volcanoes
• Some volcanoes explode with the force of an atomic bomb.
Others spill rivers of gently flowing lava.
• Make notes during the presentation to answer the questions
on your worksheet.
https://www.amnh.org/explore/ology/earth/volcanoesmagma-rising
The Saint-Pierre Volcanic Disaster 1902
1. What is the name given to an eruption of hot gases, ash and rocks? Pyroclastic flow
2. How fast does it travel? 480 kmh / 300 mph
3. On what date did the earthquakes begin? April 23rd 1902
4. What was the first material to affect a nearby town and when did it occur? Ash on May 2nd 1902
5. How high did the column of ash and fumes rise from Mount Pelée? 3km / 2miles
6. What killed 23 people? Mudflow
7. How long did the tsunami take to reach Saint-Pierre? 15 minutes
8. How many people were killed by the pyroclastic flow from Mount Soufrière? 1,565
9. On what two dates did Mount Pierre erupt? May 8th and May 20th
10. What type of rock do you think created the 300m “Needle of Pelée”? Pumice
11. Why do you think it is important to know about historical volcanic eruptions? Volcanic eruptions are one
of Earth's most dramatic and violent agents of change. Not only can they drastically alter land and water
for miles around a volcano, but tiny liquid droplets of sulfuric acid erupted into the stratosphere can
change our planet's climate temporarily.
A lava spine can either be formed by viscous lava slowly being pushed out of the vent, or by magma that has
solidified within the vent before being pushed out.
How acid rain forms
The term 'acid rain' refers
to rainfall containing strong
acids.
These can originate from
both natural sources and
human activity.
Volcanic acid rain (pH 2.5-5.0) is
dominated by hydrochloric acid (HCl)
and sulfuric acid (H2SO4) .
Acid rain practical
You are going to test some rock
samples for the presence of
carbonate minerals.
How could you increase the
rate of the reaction in these
tests?
Use ONE drop only!
GOGGLES AT ALL TIMES!
Name of rock
Effect of adding acid
What causes the fizz?
Carbonate minerals are unstable in contact with
hydrochloric acid.
When acid begins to effervesce (fizz) on a specimen, a
reaction similar to the one shown below is taking place.
CaCO3 + 2HCl → CO2 + H2O + Ca++ + 2Cl–
On the left side of this reaction, the mineral calcite
(CaCO3) is in contact with hydrochloric acid (HCl). These
react to form carbon dioxide gas (CO2), water (H2O),
dissolved calcium (Ca++), and dissolved chlorine (Cl--).
The carbon dioxide bubbles that you observe are
evidence that the reaction is taking place. When that
occurs, calcite or another carbonate mineral is present.
Environmental affects of acid rain
Lesson 4: Earthquakes and Tsunamis
What do the yellow lines on this map show?
What are earthquakes? What are plate margins?
DESTRUCTIVE
CONSERVATIVE
Earthquakes are vibrations
caused by earth movements
at plate margins and at
major fault lines (cracks in
the earth’s surface).
They can occur at all
major plate margins but
the most severe
earthquakes are normally
found at CONSERVATIVE
and DESTRUCTIVE margins.
Earthquake data
Look at today’s data from the
USGS and plot the
earthquakes on your map.
• What do you notice?
• Draw a red line around the
‘Ring of Fire’
• What is the size, depth and
location of the largest
earthquake today?
https://earthquake.usgs.gov/earthquakes/map/?cur
rentFeatureId=ak0217timl90&extent=-12.03932,201.79688&extent=68.72044,11.95313
What do you think a tsunami is?
Tsunami is a Japanese word.
It means ‘Harbour Wave’.
A tsunami is a giant wave.
Was your idea close to the real
meaning?
• A tsunami is a giant wave caused by a huge
earthquake under the ocean.
• The earthquake causes a large amount of water to
be displaced very quickly.
• A series of waves travels through the deep water.
• As the waves travel through shallower water near
the land, they get bigger.
Did you know...
before the tall
wave hits the land,
the water level at
the shore will
drop?
Watch this video which shows how a
tsunami is formed.
What can you see that looks out of place?
What kinds of damage have occurred
in the area?
If you were in a rescue team who have
just arrived at the scene, what kinds of
help might you need to give?
Photo courtesy of Official US Navy page (@flikr.com) – granted under creative commons licence - attribution
What Causes a Tsunami?
Approaching tsunamis are
sometimes predicted by a
sudden rise or fall of coastal
waters and are usually
accompanied by a loud roar
that sounds like a train or
aircraft. If you notice
these, move inland to high
ground straight away.
Stay out of danger until
an "ALL CLEAR" is issued
by the emergency
services.
Homes and other buildings
located in low lying coastal
areas are not safe. Do
NOT stay in such
buildings if there is a
tsunami warning.
The upper floors of high,
multi-story, reinforced
concrete hotels can
provide safety if there is
no time to quickly move
inland or to higher ground.
Never go down to the
beach to watch for a
tsunami! A small tsunami
at one beach can be a
giant a few miles away.
Stay tuned to your local
radio or television
stations during a tsunami
emergency.
Japan – 2011
At 2:46pm, an 8.9 magnitude earthquake struck the north
east coast of Japan. The quake triggered a huge tsunami
which swept inland. In places, the tsunami waves reached
as far as 10k inland and entire towns virtually
disappeared. Japan has the longest recorded history of
tsunamis.
Sumatra, Indonesia – 2004
This Indian Ocean earthquake and tsunami was the
most devastating of its kind in modern times, killing
230,000 people in 14 countries, and bringing waves
of up to 30m high. It was the third largest
earthquake ever recorded, had the longest duration
ever observed (8.3 - 10 minutes), and caused the
entire planet to vibrate.
Lisbon – 1755
The earthquake and
tsunami almost totally
destroyed Lisbon and had a
death toll in Lisbon alone
of between 10,000 and
100,000 people, making it
one of the deadliest
disasters in history.
Italy – 1908
The Messina earthquake and
tsunami took about 123,000 lives
in Sicily and Calabria, southern
Italy. The major cities of
Messina and Reggio Calabria were
almost completely destroyed.
Italy - 1783
The Calabrian earthquakes
were a sequence of five
strong earthquakes that
hit the region of Calabria,
the first two of which
produced tsunamis. The
death toll lies in the range
of 32,000 to 50,000
people.
https://youtu.be/Wx9vPv-T51I
Tsunamis
Complete the Tsunami worksheet
Session 3 – Could you be a geologist?
https://www.geolsoc.org.uk/careerprofiles
Exit ticket- Exam questions
Have you been inspired to study
geology today?
• https://youtu.be/O8HNlhVbGzY - Dante’s Peak film trailer 1997
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