Earthquakes and why they happen

Section	Detail
Key Ideas	Earthquake strength is measured on the Richter Scale and the intensity of their effects on the Mercalli Scale. Earthquakes happen because of the stress where tectonic plates meet.
Terms	Distribution, Richter Scale, seismograph, Mercalli Scale, focus, shock waves, epicentre.
Starter	BBC Earthquakes Video
Main	1. TDIT    2. Using H p18 answer the following questions:    What are earthquakes?    How dangerous are they?    How many earthquakes are there each year?    Where do they occur (what is their distribution or global pattern)?    What is the link with where volcanoes occur?    3. What is the difference between a seismometer and a seismograph?    4. What do the Richter and Mercalli scales measure?    5. Explain how an earthquake measuring 6 on the Richter scale is 100 times stronger than one measuring 4.    6. What number on the Mercalli scale is an earthquake likely to be if it is the top story on the BBC news? Does this depend on the country the earthquake occurs in?    7. On what type of plate boundary do most earthquakes happen? Explain why many strong earthquakes occur along destructive plate margins.    8. Why are tectonic stresses lower along constructive plate boundaries?    9. Draw a diagram to illustrate the terms; focus, shock waves, and epicentre.    10. Read eyewitness accounts of earthquake survivers http://www.bbc.co.uk/news/world-asia-pacific-12711152 http://www.geography-site.co.uk/pages/physical/earth/witness/cal1.html http://news.bbc.co.uk/1/hi/8455735.stm
Plenary	Run through 'Earth shakes, rattles and rolls' powerpoint.

BBC Earthquakes Video - Starter

Earth shakes rattles_and_rolls

View more presentations from ckzebra

How do shield and composite volcanoes form?

Section	Detail
Key Ideas	Shield volcanoes occur at constructive plate boundaries and composite volcanoes occur at destructive plate margins. Features of a volcano include magma chamber, vent, crater and layers of rock (lava) and sometimes ash.
Terms	Shield volcano, composite volcano, magma chamber, vent, crater
Starter	Violent volcanoes clip – what makes volcanoes erupt and are they all the same?
Main	1.   TDIT 2.   Students use diagram below to mark 12 volcanoes (see list below) on world map and label if they are on destructive or constructive plate margins – then say if shield or composite. 3.   Students draw and label NT p13 C&D and add 2 examples of each, country and plate margin. 4.   Volcano photo quiz
Plenary	a.   What are shield volcanoes and what type of plate margin would you find them on? b.   What are composite volcanoes? Plate margin type? c.   Name 2 shield and 2 composite volcanoes. Describe their location.

Laki

Hekla

Helgafell

Surtsey

Mauna Loa

Kilauea

Fuji

Cotopaxi

Krakatoa

Ruapehu

St Helens

Etna

What are the different types of plate boundary?

Section	Detail
Key Ideas	The 3 main types of plate boundary, destructive, contructive and conservative are all different. Examples of the boundaries are important to remember.
Terms	Convection currents, destructive margin, constructive margin, conservative margin, subduction, collision
Starter	Lava image – where is that happening? What makes it liquid? Convection currents animation
Main	1.   TDIT 2.   World map of tectonic plates 3.   Plates jigsaw 4.   Annotate plate margin cross-sections (below) using NT p10/11 D, E, F 5.   Add examples: ·         Destructive (subduction) = Nazca moving under South American – Andes Mts ·         Destructive (collision) = Indian towards Eurasian – Himalaya Mts ·         Constructive = Eurasian & North American away from each other - Mid Atlantic Ridge/Iceland ·         Conservative = Pacific & North American moving alongside each other – San Andreas Fault, California
Plenary	a.   How quickly do plates move? b.   Give an example of a conservative plate margin. c.   What happens at a destructive plate boundary? d.   How was Iceland formed?

Convection Currents

World Map of Plate Margins

Plate jigsaw