WJEC Earth

1. The theory that states that the Earth's lithosphere is divided into several large and small plates
4. Supercontinent made up of all the continents joined together. It was this that ‘drifted’ apart in the idea of continental drift
6. Rocks in the middle of the Atlantic Ocean are younger than those at the edge. This shows evidence of _____ _____ ________
8. The type of fit of the edges of the continents observed by Wegener
10. The opening at the top of a volcano
11. These are found in the mantle and cause the movement of the tectonic plates
14. Similar ones found on different continents and provide evidence for continental drift
15. The boundary where two tectonic plates collide
17. The scientist who first proposed the theory of continental drift
18. The unit of measurement for the distance moved by tectonic plates each year
20. Solid, hot and made of iron and nickel

2. The explosive release of volcanic ash, gases, and rocks
3. These form at constructive and destructive plate boundaries
5. A sudden shaking or trembling of the ground caused by volcanic activity
6. The boundary where two tectonic plates collide and one is forced beneath the other
7. The molten rock that erupts from a volcano
9. Found outside the earth's crust
12. The boundary where two tectonic plates move apart
13. The solid outermost layer of the Earth
14. The boundary where two tectonic plates slide horizontally past each other
16. Liquid iron and nickel too and very hot
19. The layer of the Earth located between the crust and the core