1. Year 3 Revision for test on tectonics
Available for download at: geographyiseasy.wordpress.com

2. The main physical features of the Earth:Learn names and location
Asia
North America
Europe
Alps
Rocky
Mountains
Himalayas
Atlantic
Ocean
Africa
Pacific
Ocean
Indian
Ocean
South America
Andes
Oceania
Southern Ocean
Antarctica

3. Definition of ‘Plate tectonics’
Definition: The theory of plate tectonics states that the Earth's crust is broken into a number of large and small slabs of rock called plates. Why is this theory very important? The formation of mountains and volcanoes, and the occurrence of earthquakes have been explained using this theory.

4. CROSS-SECTION OF THE EARTH
DIVIDED INTO PLATES WHICH FLOAT ON THE MANTLE
CRUST: SOLID THIN LAYER.
MADE OF TWO MAIN TYPES:
CONTINENTAL (60 KM THICK)
OCEANIC (8 TO 10 KM THICK)
(MUCH HEAVIER THAN CONTINENTAL)
MANTLE:MOLTEN ROCK WHICH MOVES IN CIRCLES DUE TO CONVECTION CURRENTS
THE CORE GIVES OFF INCREDIBLE HEAT WHICH CAUSES THE MANTLE TO FLOW.
Draw, label the four layers and annotate.

5. The importance of crust
There are two types of crust which have different characteristics.
Older, lighter, cannot sink and is permanent.
Younger, heavier, can sink and is constantly being destroyed and replaced.

6. World map of plate boundaries: Learn names and location.
Pacific

7. How are plate boundaries classified?
The boundaries between plates can be classified into three main types according to the direction of movement of the plates on either side of the boundary. Plates may either move away from each other (divergence), towards each other (convergence), or past each other.

8. Learn these Figures
MANTLE
MANTLE
MANTLE

9. Destructive/convergent boundaries
5-The Peru-Chile trench
forms where the
oceanic plate is being
subducted.
6-The collision causes
folding and uplift of
rocks which form fold
mountains.
4-The melting plate
creates lighter
magma that rises
towards the surface
to form volcanoes.
Andes fold mountains
Pacific
Ocean
Trench
Volcano
Nazca Plate
(Oceanic)
South American
Plate (Continental)
Earthquakes
Mantle
Subduction
zone
3-The heat from
the mantle causes
the oceanic plate
to be destroyed.
1-The Nazca Plate is being subducted below the South American Plate.
2-Friction and pressure
cause earthquakes to
occur along the subduction zone

10. Constructive/divergent boundary
4-Submarine volcanoes appear along the ridge. Some may grow to form islands, e.g. Iceland.
3-A mid-ocean ridge is formed by the new crust.
Oceanic crust
Oceanic crust
2-As the plates move apart, magma from the mantle rises to fill the gaps and forms new oceanic crust.
1-Convection currents pull plates apart.
Constructive/divergent boundary

11. Describe and explain the characteristic features of a constructive boundary. (4)
What are features? Mid-ocean ridges and volcanic islands are the features of a constructive boundary. The question asks for an explanation , i.e. the reasons for these features. You may answer this question using the ‘case study’, i.e. located example, of the Mid-Atlantic constructive boundary. Describe and explain the characteristic features of a destructive boundary. (4) Subduction zone-earthquakes-volcanoes-trenches-fold mountains

12. Learn annotations

13. Why do some volcanoes not occur on plate boundaries?... Hot spots
Some volcanoes do not occur on plate boundaries. These volcanoes are formed over hotspots. These are fixed points in the mantle that generate intense heat. Volcanoes are created if the magma rises above the ocean surface. As the crustal plate moves over the stationary hotspot, new volcanoes are formed. Hotspots are associated with chains of islands such as Hawaii.

14. As the plate moves over the stationary hotspot, new volcanoes are formed.

15. Learn the named example of hot spot
Learn the named example of hot spot. Case study: The Hawaiian Islands, which are entirely of volcanic origin, have formed in the middle of the Pacific Ocean more than 3,200 km from the nearest plate boundary. The Hawaiian Islands are located over a hotspot. The magma rises through the Pacific Plate to supply the active volcanoes.