Sc Science Y e ar 3 Scie ntists and Inve ntors Y ear One Scie - PowerPoint PPT Presentation

Sc Science Y e ar 3 Scie ntists and Inve ntors Y ear One Scie cience ce | Y e ar 3 | Scie ntists and Inve ntors | Journe y to the Ce ntre of the Earth | Le sson 4

Ai Aim • I can describe what Inge Lehmann discovered about the E arth’s core. Succes ess C Criter eria • I can describe Inge Lehmann’s life and work. • I can explain what she discovered about the E arth’s core. • I can explain how the E arth’s core helps create igneous rocks.

What’s Under er Our Feet eet? The ground we walk on feels solid. But what is underneath the ground? F or a long time, scientists wondered about this. Many people were fascinated with the idea of what was under our feet. S ome people even wondered whether there could be another inhabited world beneath the ground! Nobody can see the centre of the E arth, so scientists had to use other methods to find out the answer.

Inge L e Leh ehmann Inge Lehmann was the scientist who finally discovered what lies in the centre of the E arth. Y our Inge Lehmann Activity S heet shows a picture of Inge Lehmann, and has space to fill in facts about her life and work. Around the room you will find key pieces of information about Inge and what she discovered. Move around the room to find the facts you need to complete your activity sheet and learn more about this incredible woman.

The e Cen entre o e of t the E e Earth Inge discovered that below the E arth's surface was a solid core surrounded by molten liquid rock. Before her discovery, scientists thought that the E arth's core was liquid too. Her ideas explained the strange readings from earthquake waves that had previously puzzled scientists. Thanks to Inge's work, we now know that the E arth's core is made of solid iron and nickel, and that it is about as hot as the surface of the S un! It has a radius of about 1220km, so it is slightly smaller than the Moon. The E arth's core is solid because of the pressure from the outer layers of the E arth pushing down on it.

The e Cen entre o e of t the E e Earth The immense heat of the E arth's solid core is enough to melt rocks. This melted rock is known as magma. Magma makes up a layer between the E arth's core and the ground. As the magma cools near the surface or the E arth, it starts to turn back into solid rock. The rocks formed by cooling magma are called igneous rocks. E xamples of igneous rock include pumice, granite and obsidian. pumice granite obsidian

Earths Layers Ea Core Inner Although this is the hottes t part of the E arth (with temperatures reaching 5500°C) it is actually s olid. It is made up of Iron and Nickel; thes e qualities were dis covered by the s cientis t, Inge Lehmann. r ore Oute This surrounds the solid inner core, but the material in this section is liquid. It is also made of iron C and nickel that has been melted by the high temperatures. Mantle This is the wides t layer making up the E arth at a thicknes s of nearly 3000km! The material here is a mix of rock and s emi-molten (melting) rock called magma. t Crus This is the outer layer of the E arth and the bit that we live on. It is not very thick (between 0-60km) and is broken up into ‘plates ’ that are s lowly moving.

Ea Earths Layers Using your Layers of the E arth Activity S heet, write some information about each of the earths layers in the spaces provided. Can you find out any more information about the earth’s layers? S ee how many facts you can find and add them to your activity sheet!

Ai Aim • I can describe what Inge Lehmann discovered about the E arth’s core. Succes ess C Criter eria • I can describe Inge Lehmann’s life and work. • I can explain what she discovered about the E arth’s core. • I can explain how the E arth’s core helps create igneous rocks.