Earth Structure and Plate Tectonics By the end

Earth Structure and Plate Tectonics By the end of this lesson you will: • Know the structure of the Earth’s interior • Understand plate tectonics and their movement

What is this? Digital Vision 9 (NT)

WALT What is the structure of the Earth? WILF All students are able to recall the structure of the Earth ( grade D ) Most students are to describe what are tectonic plates and how they move by convection currents ( grade C ) Some students are able to explain continental drift and what happens at plate boundaries ( grade B )

Starter 1. Which metals are found at the centre of the Earth? 2. How thick is the Earth’s crust? 3. How were the Himalayan mountains formed? 4. Where do we find volcanoes? 5. Why do earthquakes happen? 6. Who is Wegener?

Key Words Core crust convection currents mantle tectonic plates continental drift

The Earth’s Structure Beneath the atmosphere the Earth consists of 3 main layers:

The Structure of the Earth A thin crust 10 -100 km thick A mantle – has the properties of a solid but it can also flow A core – made of molten nickel and iron. Outer part is liquid and inner part is solid The average density of the Earth is much higher than the crust, so the inner core must be very dense

What am I? • I am dense, very hot, made mostly of solid iron and nickel. Inner core • I’m iron and nickel too, but I’m liquid. • I’m really very thin and am mostly silicon, Crust oxygen and aluminium • I’m a viscous semi-solid with convection Mantle currents circulating in me. • I just hang around on the outside. Outer core Atmosphere

How am I doing? Were you able to answer the questions? YES ? Well done you have achieved WILF 1 All students are able to describe the structure of the Earth ( grade D )

Tectonic plates • • The crust is made of about twelve plates These are like big rafts floating on the semi-molten mantle. Convection currents within the mantle cause the plates to move. Although they only move about 2 cm/year this can have huge effects over long periods of time.

Movement of the Lithosphere crust The Earth’s LITHOSPHERE (i. e. the _______) is split up into different sections called ____ plates: tectonic These plates are moving apart from each other a few centimetres every _______ due to the year convection ____ currents in the mantle caused by the radioactive ____ decay of rocks inside the core. Words – radioactive, crust, convection, tectonic, year

How am I doing? Were you able to complete the sentences? YES ? Well done you have achieved WILF 2 Most students are to describe what are tectonic plates and how they move by convection currents ( grade C )

Continental Drift

Introducing plate tectonics

Evidence for Continental Drift The theory is supported by several pieces of evidence. For example, if we consider Africa and South America there is: – The “jig-saw fit” – The similarities in the rock layers from Africa and South America. – Similarities in the type and age of fossils. – Evidence of related species that definitely did not swim the Atlantic Ocean! Jig Saw fit Similar rocks and fossils

Task Working in a pair Write your own explanation for plate tectonics and continental drift using the information given to you by your teacher and text book Include a section on what evidence is available to support the idea of continental drift

WALT What is the structure of the Earth? WILF All students are able to recall the structure of the Earth ( grade D ) Most students are to describe what are tectonic plates and how they move by convection currents ( grade C ) Some students are able to explain continental drift and what happens at plate boundaries ( grade B )

Plate boundaries

Activity • Find the words and write a sentence about how each one has something to do with plate tectonics. – Drift – Earthquake – Fossil – Jigsaw – Magma – Pangaea – Plates – Subduct – Volcano