An earthquake occurs when rocks underground release stored energy, causing the ground to shake. Earthquakes are usually caused by the movement of tectonic plates. They can cause damage and loss of life through mechanisms like fires, landslides, floods, and tsunamis. Scientists measure earthquakes using seismographs which record seismic waves. The location and magnitude of quakes are determined by analyzing these wave recordings. Major quakes pose risks like liquefaction of soils and large tsunami waves.
Neo4j - How KGs are shaping the future of Generative AI at AWS Summit London ...
Earthquakes
1.
2. Earthquake Information
EARTHQUAKE INFORMATION
An earthquake is when the ground is shaken caused by rocks
releasing energy. Earthquakes, also known as tremors, are
caused when the plates inside the earth move or crash into each
other. Earthquakes normally occur over plate boundaries.
Earthquakes cause many deaths. It is said that about 10,000
people die yearly from earthquake eruptions. Earthquakes can
cause fires, mud slides, floods, and tsunamis. Usually after
massive earthquakes little ones happen shortly after.
Here is a few facts:
-The worlds largest earthquake was a 9.5 earthquake in Chile on
May 22, 1960.
-The first earthquake that we know of was in California about 50
kilometres away from Los Angeles in 1769.
-It is said that there are about 500,000 earthquakes around the
world each year. About 100,000 of them we can feel and about
100 of them cause damage.
Weird fact:
Earthquakes can happen on the moon they are called
moonquakes. They are not very big but they still do happen.
Information from-
http://earthquake.usgs.gov/learn/facts.php
and
http://environment.nationalgeographic.com/environment/natural-
disasters/earthquake-profile/
and
BC SCIENCE 7 Textbook
and
http://scienceblogs.com/deanscorner/assets_c/2011/03/ss-110311-japanquake-
01_ss_full-thumb-1200x791-62422.jpg
3. Faults
FAULTS
A fault is where the Earth has cracked open.
This shows that there has been an
earthquake. Big faults show that the tectonic
plates have been pushing together very hard.
There are three different types of faults that I
will be talking about:
-Normal Faults
-Reverse Faults
-Strike Slip Faults
Interesting fact:
-The fault in San Andreas California caused
chaos, many people were injured during this
time.
Information from-
http://en.wikipedia.org/wiki/Fault_(geology)
and
BC SCIENCE 7 Textbook
and
http://blogs-
images.forbes.com/moneybuilder/files/2011/08/earthquake.jpg
4. Normal Faults
NORMAL FAULTS
A normal fault is where the
rock above the fault moves
down and the fault below
moves up. Normal faults
usually happen where the
lithosphere is being stretched.
Other times it happens near
deltas, at the end of big lumps
of sand or mud.
information from-
http://www.see.leeds.ac.uk/structure/faults/normal/index.htm
and
http://geomaps.wr.usgs.gov/parks/deform/gfaults.html
and
BC SCIENCE 7 Textbook
and
http://www.sleepingdogstudios.com/Network/Earth%20Scie
nce/ES_11.2A_files/slide0010_image022.jpg
5. Reverse Faults
REVERSE FAULTS
Reverse faults are cracks,
in the crust, where one of
the plates are pushing up
into another plate. Or
when the plate is folding
up because it is being
pushed by another plate.
In a reverse fault the rock
that is above the fault is
pushed up and over the
rock below the fault.
Information from-
http://www.geo.mtu.edu/UPSeis/where.html
and
BC SCIENCE 7 Textbook
and
http://www.public.asu.edu/~ntoke/block-
reversefault.jpg
6. Strike Slip Fault
STRIKE SLIP FAULTS
A strike slip fault is when the two
rocky blocks rub side by side. If
the block rubs to the left it is
called a left lateral. If the block
rubs to the right it is called a right
lateral. The result of this fault’s
motion is caused by strong
cutting forces. The strike slip fault
is studied the most out of all the
faults. Strike slip faults are also
the longest fault out of them all.
Information from-
http://www.iris.edu/gifs/animations/faults.htm
and
http://geomaps.wr.usgs.gov/parks/deform/gfaults.html
and
http://www.tinynet.com/faults.html
and
BC SCIENCE 7 Textbook
and
http://www.consrv.ca.gov/cgs/information/publications/teach
er_features/PublishingImages/strike-c.gif
7. Seismic Waves
SEISMIC WAVES
A seismic wave is a wave of
energy that travels rapidly
through the Earth, and causes an
earthquake. Seismic waves are
studied by seismologists and
geophysicists. The speed of the
waves depend on how dense
they are. The speed starts to gain
the deeper the wave is. it goes
about 2 to 8 kilometres in Earth’s
crust and about 13 kilometres in
the mantle.
Information from-
http://en.wikipedia.org/wiki/Seismic_wave
and
BC SCIENCE 7 Textbook
and
http://www.eoearth.org/files/114201_114300/114212/Epicen
ter_diagram.gif
8. Primary Waves
PRIMARY WAVES
Primary waves are one of the kinds of
body waves that happen during an
earthquake. A primary wave is one of
the main waves that occur after an
earthquake. A primary wave is the
fastest kind of seismic wave. Primary
waves go as fast as 1450 miles per
hour in the air and 500 miles per hour
in granite. Primary waves move like a
slinky.
Fact
-A primary wave is called that because
it is the first wave to appear during an
earthquake
-Animals can actually hear the primary
waves going through the air.
Information from-
http://www.universetoday.com/85000/p-waves/
and
BC SCIENCE 7 Textbook
and
http://cse.ssl.berkeley.edu/img/earthquakes/PWave.gif
9. Secondary Waves
SECONDARY WAVES
A secondary wave is another type
of body wave that occur during an
earthquake. Secondary waves
move like waves in a rope. The
secondary wave can only go
through liquid not solid things like
the primary wave can.
Fact
-A secondary wave is called that
because it is the second wave to
appear during an earthquake.
Information from-
http://en.wikipedia.org/wiki/S-wave
and
BC SCIENCE 7 Textbook
and
http://regentsprep.org/regents/earthsci/graphics/swave.jpg
10. Surface Waves
A surface wave is yet
again another type of
body wave that occurs
during an earthquake. A
surface wave is the
slowest wave that
occurs. Surface waves
cause the most damage
during an earthquake.
Surface waves move
just like secondary
waves.
Information from-
http://electriciantraining.tpub.com/14182/css/14182_76.htm
and
BC SCIENCE 7 Textbook
and
http://earthquake.usgs.gov/learn/eqmonitoring/eq-mon-
1.php
11. Locating an Earthquake
LOCATING AN EARTHQUAKE
When an earthquake occurs the
first question asked is where was
the earthquake? Scientists use
the time of the seismic waves to
show the locations. Well primary
waves are faster than secondary
waves. So it is possible to
determine where the earthquake
was by measuring the time when
they got there. The further the
waves are the further the
earthquake stretches.
Information from-
http://earthquake.usgs.gov/learn/faq/?categoryID=2&faqID=
118/index.html
and
BC SCIENCE 7 Textbook
and
http://assets.knowledge.allianz.com/img/earthquake_measu
ring_french_nationa_seismic_survey_institute_seismic_wav
es_seismograph_m_16574.jpg
12. Hypocentre
HYPOCENTRE
Where the earthquake
happens in the Earth is
where the hypocentre is,
also known to be called
the focus. The primary
and secondary waves
come out of the
hypocentre.
Information from-
http://www.wisegeek.com/what-is-an-
epicenter.htm
and
http://www.eoearth.org/article/Hypocenter
and
BC SCIENCE 7 Textbook
and
http://www.empr.gov.bc.ca/Mining/Geoscience/S
urficialGeologyandHazards/Earthquakes/Publishi
ngImages/eq-2b.gif
13. Epicentre
EPICENTRE
Where the earthquake
starts on the surface it is
called the epicentre. The
epicentre is directly above
the hypocentre. The
epicentre is directly above
the place where the fault
begins. The surface waves
come from the epicentre.
Information from-
http://www.wisegeek.com/what-is-an-
epicenter.htm
and
http://en.wikipedia.org/wiki/Epicenter
and
BC SCIENCE 7 Textbook
and
http://earthquakesandplates.files.wordpress.c
om/2008/05/epicenter.gif
14. Seismograph
SEISMOGRAPH
A seismograph is an tool used
to measure earthquakes.
Seismographs have a heavy
pendulum with a needle out
above a revolving drum. The
drum has a device that makes
the needle move and make
drawings. This is how it
records earthquakes.
Information from-
http://www.bookrags.com/research/seismograph-woes-02/
and
BC SCIENCE 7 Textbook
and
http://earthquake.usgs.gov/learn/glossary/?term=seismogra
ph
15. Bedrock
BEDROCK
Earthquakes happen along
faults, tectonic plate
boundary zones or along
the mid oceanic ridges. At
these spots there are big
amounts of rock that slide
past each other and can
become stuck because of
friction. The friction is
overpowered when the
stress has enough force to
cause a slip in the rock.
Information from-
http://www.eoearth.org/article/Earthquake
and
BC SCIENCE 7 Textbook
and
http://earthquake.usgs.gov/learn/glossary/?term=bedr
ock
16. Seismogram
SEISMOGRAM
When an earthquake occurs a
seismograph takes a reading on
everything that happened the
results of the readings and
measurements is called a
seismogram. Many years ago a
seismogram was a pencil
connected to a spinning drum the
pencil would draw a lot of lines.
All of these lines show you the
seismic waves and other activity
during the earthquake.
Information from-
http://www.annalsofgeophysics.net/Seismogram_measuring_the_e
arths_movement.html
and
BC SCIENCE 7 Textbook
and
http://earthquake.usgs.gov/learn/glossary/?term=seismogram
17. Measuring Earthquakes
MEASURING EARTHQUAKES
The size of the earthquake
depends on the size that the fault
was and the size of the slip on
the fault. Scientists can not just
measure earthquakes with a
measuring tape since the faults
are kilometers deep in the Earth’s
crust. Scientists use seismogram
readings made on a seismograph
at the Earth’s surface to show
how large it was. When a small
line is drawn that shows that is
was a small earthquake and
when a big line is drawn it shows
that there was a big earthquake.
Information from-
http://earthquake.usgs.gov/learn/kids/eqscience.php
and
BC SCIENCE 7 Textbook
and
http://www.seismosoc.org/publications/SRL/SRL_73/EQ73-
6.f1.gif
18. Richter Scale
RICHTER SCALE
Seismologists use a
method called the
Richter scale. This
scale shows the
magnitude that the
earthquake was. The
scale shows all
earthquakes
magnitude from 0 to
10.
Information from-
http://earthquake.usgs.gov/learn/topics/richter.php
and
BC SCIENCE 7 Textbook
and
http://mishunderstanding.files.wordpress.com/2011/01
/richter-scale.gif
19. Tsunamis
TSUNAMIS
Some earthquakes happen
under water, this causes
the water to get disrupted
so the waves start to get
bigger. The waves will get
very massive after a little
while and start coming
towards land and cause
major damage where the
massive wave hits.
Information from-
http://www.ess.washington.edu/tsunami/general/physi
cs/earthquake.html
and
BC SCIENCE 7 Textbook
and
http://topnews.in/usa/files/tsunami-wave.jpg
20. Liquefaction
LIQUEFACTION
When an earthquake occurs the
ground shakes and causes wet
soil to act like it is now liquid. The
liquid like soil will start to sink
down underneath buildings and
cause them to collapse. This
does not always happen
underneath buildings it can
happen anywhere.
Information from-
http://ecan.govt.nz/advice/emergencies-and-
hazard/earthquakes/pages/liquefaction-information.aspx
and
BC SCIENCE 7 Textbook
and
http://upload.wikimedia.org/wikipedia/en/thumb/4/42/Liquefa
ction_at_Niigata.JPG/400px-Liquefaction_at_Niigata.JPG
and
http://www.digitaljournal.com/img/8/4/7/1/2/1/i/8/4/3/p-
large/IMG_6825.JPG