Big Picture: What are earthquakes and where do they occur? Lesson 1/2 • Know what an earthquake is. • Be able to categorise the types of waves earthquakes emit. • Locate named examples of recent earthquakes onto a world map.

Connect: How much do you already know about earthquakes? Take the mini quiz! â&#x20AC;˘ http://news.bbc.co.uk/cbbcnews/hi/newsid_4140000/new sid_4146100/4146125.stm

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Activate: What is an earthquake? Christchurch, New Zealand 2010 http://www.y outube.com/ watch?v=HTySEWxb mc

Demonstrate: What is an earthquake?

An earth quake is a sudden and brief period of intense ground shaking. They occur when the plates in the earths crust collide or move past each other (at constructive and destructive plate margins) . Task: Using this definition, the information on page 24 and what you already know about earthquakes, write your own definition of what you think an earthquake is.

Q. How can earthquakes be measured? • A. By measuring the types of wave they emit during a movement. • There are 4 different types of wave… – – – –

1. Primary waves 2. Secondary waves 3. Transverse waves 4. Longitudinal waves

Primary (P) and Secondary Waves (S) • These occur deep in the earths crust.

– http://www.classzone.com/books/earth_science/terc/content/visualiza tions/es1002/es1002page01.cfm?chapter_no=visualization

• P waves compress the rock through which they travel, while S-waves distort its shape or shear it.

– http://www.pbs.org/wnet/savageearth/animations/ear thquakes/index.html

Can you create this movement with the slinky?!

Longitudinal and Transverse Waves • These occur on the surface later on. • Longitudinal waves have a move up and down movement.

• Transverse waves cause side to side movement.

What is the focus and the epicentre? •

http://highered.mcgrawhill.com/olcweb/cgi/pluginpop.cgi?it=swf::640::480::/sites/dl/ free/0072402466/30425/16_04.swf::Fig.%20%2016.4%20%20Focus%20of%20an%20Earthquake

• The focus of the earthquake occurs deep in the earths crust and is the exact point at which the earthquake is triggered. • The epicentre is the point at the earths crust directly above the focus.

Which type of wave do you think cause more damage to buildings?

Lesson Focus: Where do earthquakes occur? Lesson 1/2 • Know what an earthquake is. • Be able to categorise the types of waves earthquakes emit. • Locate named examples of recent earthquakes onto a world map.

Connect: Today is a skills building lesson. Can you locate the following places on your world maps?

Activate: Create your own annotated sketch of how a earthquake occurs.

• Use the diagram A page 24 to help you. • Your diagram needs to have the following labels. – – – – – –

Transverse waves Longitudinal waves Primary waves Secondary waves Focus Epicentre

Activate: Where do earthquakes occur? • Read the information on page 25 which describes where earthquakes occur. • Task: Summarise the information to explain where they are located.

• Extension: Highlight the important geographical terms.

Demonstrate: Today’s task! • Part A: You are going to develop your geographical skills by locating a the earthquakes that have occurred over the world in the last 7 days! • Group which maps the most locations wins! • Winning group = 3 merits each!

• http://www.bbc.co.uk/schools/gcsebitesize/geograph y/natural_hazards/tectonic_plates_rev2.shtml

Number 1: We will do together!

Reflect: Look at your world maps; can you spot any patterns? • In your books answer the following questions… • 1. Which area of the world has the most earthquakes? • 2. Are their any areas which have no earthquakes at all? • 3. Can you explain why earthquakes are distributed in this way?

Evaluate: In California (USA) has an earthquake happen every day. How do you think people adapt to living with them in this part of the world? â&#x20AC;˘ http://quakequizsf.org/

restless earth, 14 15

restless earth, 14 15