1. Contemporary science issues
Lesson 14: Journey to the centre of the Earth
Main Activity 1 – evidence cards
© Gatsby Technical Education Projects

2. Evidence card Evidence card Evidence card Evidence card
We have little direct evidence of what is inside the Earth. The composition of the mantle has been examined mainly through samples obtained from volcanic activity. A small amount of mantle rock has been obtained by direct drilling.
Evidence card
Some rare meteorites are made of rock containing a large proportion of iron and nickel.
(5)
(1)
Evidence card
Iron-nickel meteorites are much denser than most Earth rocks. They are even denser than rock samples that have been drilled from beneath the crust (from the mantle).
Evidence card
The density of the Earth is higher than that of any other planet in our solar system.
(9)
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3. Iron and nickel are magnetic materials.
Evidence card
The average density of the Earth is approximately 5.4 grams per centimetre cubed (5400 kg per cubic metre). The density of water is 1g/cm3.
Evidence card
The densities of iron and nickel are nearly 8000 and 9000 kg/m3 respectively.
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Evidence card
The density of rock obtained from the mantle beneath the crust is 4500 kg/m3.
Evidence card
Iron and nickel are magnetic materials.
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4. Evidence card Evidence card
The average density of rocks from the Earth’s surface is 2700 kg/m3.
Evidence card
The Earth has a magnetic field around it.
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