The Changing World Structure of the Earth
Bristol If you start on the Earth’s surface how far down would you go if you travelled the same distance as the distance between London and: Barcelona New York Paris
The distance from London to: Bristol = 200 km New York = 5586 km Barcelona = 1183 km Paris = 343 km
Deepest mines in the world = 3 500 m Deepest geological survey = 12 000 m The Earth is 12 800 000 m in diameter 1000 x deeper than our deepest hole The Earth is made of many layers Formed millions of years ago Heavy matter sank to middle Lighter matter floated on top Structure of the Earth
The Earth’s Structure Beneath the atmosphere the Earth consists of 3 main layers:
The temperature is high and the outer core is molten. Towards the centre high pressure makes the inner core solid. Intense heat is generated in the inner core by decay of radioactive elements like uranium. 1300 km 1110 km 3000 km The core The core extends to about half the radius of the Earth. It is made mostly from iron and nickel and is where the Earth’s magnetic field comes from. It is very dense. 5500 C Inner core Outer core
How many parts make up the Earths core? What are they? Challenge: Why is the hotter part of the core solid, while the cooler part is liquid?
The mantle extends outwards from the core to the crust: a distance of about 2,900 km. It is mostly a semi-molten liquid upon which the Earth’s crust floats. The heat coming from the core generates convection currents in the viscous mantle that cause the crust above to move. 2900km The mantle Mantle
What is the layer of our planet surrounding the core called? Challenge: This layer is not a liquid, but is often described as ‘syrupy’. Why is this?
The crust is the thin layer of rock at the surface upon which we live. Eight elements make up over 98% of the Earth’s Crust – although they are virtually entirely in the form of compounds. % 20-60 km The crust Crust
What is the outer layer of the Earth known as? Challenge: Why do scientists think that the core is made of much denser material than the crust?
By studying earthquakes Seismic waves travel through the Earth The way the waves travel tells us what they’re travelling through Features on the surface Cooling of the crust – cracking Actually movement of plates How do we know?
I am dense, very hot, made mostly of solid iron and nickel. I’m iron and nickel too, but I’m liquid. I’m really very thin and am mostly silicon, oxygen and aluminium I’m a viscous semi-solid with convection currents circulating in me. I just hang around on the outside. What am I? Inner core Outer core Crust Mantle Atmosphere
Attach labels to the correct part of the diagram. Atmosphere Outer core Crust Mantle Inner core