What is an earthquake? Imagine this, click on the speaker
button (Spilsbury, 2004) An earthquake is the shaking of the ground
as a result of movement of tectonic plates located on the outer
layer of the Earths surface. The moving plates send out shock waves
that can be strong enough to change the surface of the Earth
pushing up rock faces and leaving gapping cracks in the ground.
Cause huge destruction by destroying buildings and structures such
as bridges. Breaking power and gas lines and causing fire.
Triggering natural events such as landslides, volcanic eruptions
and tsunamis. Causing loss of life (vtaide, n.d)
Slide 4
What causes earthquakes? The outer surface of the Earth called
the crust is made up of layer solid rock which make the land the
(continental plate) and the oceans the (Oceanic plate). These
plates move very slowly around the Earth floating on hot liquid
rocks found in the upper mantle. As the plates move they slide and
grind along side each the boundary that they rub along is known as
a fault. This movement is called transform boundaries, sometimes
two plates get caught on each other this causes friction and builds
up a huge amount of pressure that needs to be released. The energy
is released from the fault in all directions producing seismic
waves (Spilsbury, 2004)
Slide 5
Watch this clip http://www.youtube.com/watch?v=VSgB1IWr6O4
Slide 6
Earthquakes Where the earthquake begins below the Earths
surface is called the hypocentre. The area on the Earths surface
directly above were the earthquake started is called the epicentre.
Sometimes an earthquake can have foreshocks before the main shock
and then after the main shock aftershocks will occur which can
lasts for weeks and months after the main earthquake (Spilsbury,
2004). Earthquakes are recorded on seismographs which make a
recording called a seismogram. The size of an earthquake is called
a magnitude (USGS, 2012). Earthquakes are measured on a Richter
scale, which is rated on how much damage an earthquake has caused.
The stronger the earthquake the higher the number.
Slide 7
Magnitude Scale
Slide 8
Where do earthquakes occur? Earthquakes can happen all around
the Earth on continental plates and oceanic plates. Most of them
occur at the meeting of two plates on tectonic boundaries however
some can happen in the middle of a plate (Spilsbury, 2004). Some
regions are more prone to Earthquakes than others. The edge of the
Pacific plate has frequent earthquakes particularly in areas such
as New Zealand, Vanuatu, Solomon Islands, Papua New Guinea, Japan,
America and in Indonesia where the Indo- Australian Plate collides
with the Eurasian Plate. Although Australian does not sit on the
edge of a plate it can still experience earthquakes because the
Indo- Australian plate is being pushed north which makes it bump
into the Eurasian, Philippine and Pacific Plates. Adelaide is at
most risk of having an Earthquake in Australia. Interesting fact:
There are on average 80 earthquakes of magnitude 3.0 or more in
Australia each year. Earthquakes above magnitude 5.5, such as the
5.6 magnitude event in Newcastle in 1989, occur on average every
two years. About every five years there is a potentially disastrous
earthquake of magnitude 6.0 or more. (Australian Government
Geoscience, 2012)
Slide 9
Watch this clip Japans Tsunami
http://www.youtube.com/watch?v=oWzdgBNf hQU
Slide 10
A Challenge Listen up (Adapted from The Ohio State University,
2012)
Slide 11
Reference List Australian Government Geoscience Australia.
(2013). Hazards where do earthquakes occur? Retrieved 25 October,
2013 from
http://www.ga.gov.au/hazards/earthquakes/earthquake-basics/where.htmlhttp://www.ga.gov.au/hazards/earthquakes/earthquake-basics/where.html
National Geographic. (2011). Earthquakes 101 youtube clip.
Retrieved 25 October, 2013 from
http://www.youtube.com/watch?v=VSgB1IWr6O4 National Geographic.
(2011). Earthquakes: Rare video Japan Tsunami. Retrieved 25
October, 2013, from http://www.youtube.com/watch?v=oWzdgBNfhQU
Splisbury, L & R. (2004). Shattering Earthquakes. Great
Britain: Harcourt Education Ltd The Ohio State University. (2012).
Middle school math and science. Retrieved 25 October, 2013, from
http://msms.ehe.osu.edu/2012/03/06/building-quake-resistant-structures-in-the-classroom/
USGS. (2012). The science of earthquakes. Retrieved 25 October,
2013, from http://earthquake.usgs.gov/learn/kids/eqscience.php What
is an earthquake? (n.d.). Retrieved 25 October, 2012 from
http://www.vtaide.com/png/George/earthquake.htm Images Christchurch
earthquake House [Image].(n.d.) Retrieve 25 October, 2013, from
https://www.google.com.au/search?q=earthquake&hl=en&qscrl=1&rlz=1T4ADSA_enAU477AU477&source=lnms&
tbm=isch&sa=X&ei=TD9sUsfLLaiTiQfruIGICQ&sqi=2&ved=0CAcQ_AUoAQ&biw=1438&bih=596#facrc=_&imgdii=_&imgrc=L94gM
QRydMF-
XM%3A%3BHdwFEQnAx5bXmM%3Bhttp%253A%252F%252Fimages.brisbanetimes.com.au%252Ffile%252F2011%252F02%252F2
3%252F2199285%252Flarge2.jpg%3Bhttp%253A%252F%252Fwww.brisbanetimes.com.au%252Fchristchurch-
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