160 likes | 308 Views
Do Now!. Watch the live update link and describe what it is that you are seeing. Based upon what you have studied so far can you see any links? http://www.iris.edu/seismon /. What happens in an earthquake?. Key words
E N D
Do Now! • Watch the live update link and describe what it is that you are seeing. Based upon what you have studied so far can you see any links? • http://www.iris.edu/seismon/
What happens in an earthquake? Key words Focus= the point within the earth where the seismic waves of an earthquake start Epicentre= the point above the focus on the earth’s surface Seismic waves= waves of energy in an earthquake Friction = rub against Tension= energy that builds up LOI can describe what happens in an earthquake SkillI can reflect on how to improve my work
Starter Who can remember? List the types of plate boundaries that earthquakes occur on…
Activity 1 - What does it feel like when an earthquake occurs? Watch the following clip of an actual earthquake… http://www.youtube.com/watch?v=JWtA-TxRO7A&feature=related What would they be thinking and feeling?
Activity 2 - What happens when an earthquake occurs? • Watch the Boardworks animation (next 5 slides). Look carefully at what happens in an earthquake • Take notes using the key words • Now describe in a paragraph what happens when an earthquake occurs… EXTENSION - Make sure you use the following words: Tension Focus Epicentre Seismic waves Friction
How are earthquakes measured? The Richter scale can be used to measure the magnitude (power) of a tremor using an instrument called aseismograph. It is a logarithmic scale which means that a size ‘6’ earthquake on the Richter scale is 10 times larger than a size ‘5’ and 100 times larger than a size ‘4’.
The Mercalli Scale The Mercalli scale rates an earthquake's magnitude based on observations of the damage it causes on a scale of 1 to 12. Items shake from shelves: scale 5 Buildings collapse: scale 10
Plenary • What number on the Richter Scale would you give the following earthquakes… a b c d e
TRUE OR FALSE??? • Focus is the place on the surface of the earth directly above the epicentre • Seismic waves are waves of energy that travel out of the focus • Epicentre is the place in the earth’s crust where the tectonic plates move causing the earthquake • Tension stops the plates moving past each other • Friction stops the plates moving past each other