Finding Out About The Structure Of The Earth
(All textbook references are for the Earth Science textbook)
Station 1: Layers Of The Earth
1. Colour the “Layers of the earth” worksheet on the back of this sheet.
2. Use page 312 from the textbook to help you to label the layers.
Station 2: How Do Seismic Waves Provide Evidence About the Structure of the Earth?
1. Try dropping a marble into the water in the washing up bowl and observe the pattern of ripples, these ripples are examples of waves. This is described on page 308.
2. Use the information on pages 308 and 309 and the wordbank to complete the passage below.
When an Earthquake happens shock ______are sent through the Earth. These shock waves are called ______waves. The two main types of seismic waves are known as ______waves and
S waves. Both types of waves travel well through solids but S waves are ______by liquids and P waves find it more difficult to travel through a liquid than a ______. After an earthquake, scientists use an instrument called a ______to measure the strength of S waves and P waves at different ______around the planet. From this information they have been able to work out that the Earth is made up of different ______and some of these layers are liquid.
3. Use the slinky to model the two different types of seismic waves. Use figure 11-5 on page 351 to work out which wave is which and draw a diagram of each.
Station 3: Convection Currents In The Mantle
1. Turn to page 384 in the book to see a diagram of convection currents in the mantle.
2. Add the words cooler, current,less, mantle, plates to complete the sentence below.
A convection ______is formed when warmer, ______dense material rises to replace
______more dense material. The convection currents in the ______are believed to cause
the movements of the ______in the theory of plate tectonics.
3. Carry out the following experiment to observe convection currents in water.
(i) Place 200ml of water in a 250ml beaker.
(ii) Support this with a clamp and stand above a candle. Use the plasticine to make a base for the candle.
(iii) Light the candle.
(iv) Use the straw to carefully lower a potassium permanganate crystal into the water and heat with the candle.
(v) Watch the colour of the potassium permanganate spreading to see a convection current.
(vi) Draw a diagram of what you have observed.
Station 4:The Earth’s Magnetic Core
1. Pick up two magnets, the red ends (poles) are North and the blue ends are South. Try approaching the different ends towards one another.
2. Use the wordbank to help you to complete the following passage:
Magnets have two ______, North and ______. Two North poles will ______one
another but a North and South pole will ______.
3. Use the wordbank above and pages 310 and 311 to complete the following sentences:
Scientists think the inner core spins inside the outer core creating a ______field. This is possible because the outer core is a ______and the inner core is a ______. Both sections of the core are made from ______and nickel.
5. Use the equipment provided to observe the magnetic field around a magnet.
Station 5: Is the Mantle a Solid or a Liquid?
1. Look through pages 312 and 313 to find out about the mantle.
2. You are now going to try the cornstarch and water experiment. You will need to wash your hands after this.
(i) First approach the cornstarch with your fingertips. Can your fingertips enter the cornstarch? Is the cornstarch acting like a solid or liquid?
(ii) Now try to hit the cornstarch with the flat of your hand. The harder you try to hit it the better. Can your hand enter the cornstarch? Is the cornstarch acting like a solid or liquid?
(iii) Write down your observations about cornstarch and water below.
______
______
______
3. You probably noticed that the cornstarch and water mixture sometimes seems like a solid and sometimes seems like a liquid. The mantle also has combined properties of a solid and liquid.
Write a comment about the mantle.
______
______
Extension Activities
1. Look at Figure 9-3 on page 310 and make notes in your exercise book explaining what you see. This links with the work you did on station 3.
2. Read pages 350 and 351, what is the third type of seismic wave called? Try to model this using a slinky.
3. The strength of earthquakes can be measured using Richter or Mercalli Scale. Carry out some research to find out more about these scales, page 353 is a good place to start.
4. Try the brain pop quiz on the Earth’s structure.
http://www.brainpop.com/science/theearthsystem/earthsstructure/
JS2011 Structure Of The Earth