1. Draw a cross section of the earth and label it with the correct names and characteristics
crust - relatively thin and rocky (Oceanic 30-50km and continental 6-8km) - LITHOSPHERE!
mantle - has the properties of a solid, but can flow very slowly km, oC – ASTHENOSPHERE
outer core - made from liquid nickel and iron km, oC
inner core - made from solid nickel and iron

2. Where does the heat come for the convection currents?
How is the earth heated?
Where does the heat come for the convection currents?
Radioactive decay of uranium in the core raises the temperature to over 5000oC
Heat moves from the core to the surface in plumes. These bring magma to the surface

3. Magnetic field
The Earth also has a magnetic field as a result of the outer core – the liquid iron acts as an electric dynamo and produces the field
This field protects us from the sun’s harmful radiation

4. What are the commands in this question?
Plate boundaries
Typical exam question: (4Marks) Explain why earthquakes happen on destructive plate margins. You may draw a diagram to help your answer.
What are the commands in this question?
Have a go!

5. What did you get?

6. A* answer I find diagrams easier than Writing…. Draw a labelled
A Destructive margin is where 2 plates collide. One plate is sub-ducted under the other one. Usually a oceanic plate is sub-ducted under a continental plate. There is friction between the two plates. The pressure builds and eventually gives way, The energy release is the land shaking, called an earthquake.
I find diagrams easier than
Writing…. Draw a labelled
Diagram to help answer the Q

7. Constructive Plate Boundary

15. The oceanic crust melts and rises
Name this plate boundary. G A B E F D C
Continental crust
Mantle
The oceanic crust melts and rises
Explosive volcanoes
Oceanic plate
The oceanic crust sinks under the less dense continental crust
Earthquakes occur due to friction
Match the labels to the letters

17. A B C F D E G Named Continents Named Plates Use of Keywords
Clear Descriptions
Clear Explanations A B C F D E G

18. Volcano types
Watch the video and sketch the different types of volcano with their characteristics

19. There are 3 different types of volcanoes:
Active - eruptions can be anytime and often.
Dormant - has been a while since it has erupted, but could at anytime.
Extinct, meaning it hasn't erupted in a very long, long time so it probably won't ever again.

20. Pyroclastic flow fast-moving current of superheated gas
can reach temperatures of about 1,000 °C
rock which reaches speeds moving away from a volcano of up to 700 km/h

21. Lava flow Lava is molten rock that flows out of a volcano
Depending on its composition and temperature, lava can be very fluid or very sticky (viscous).
Fluid flows are hotter and move the fastest; they can form streams or rivers

25. Cinder cone volcanoes Cinder cones
build from lava that is blown violently into the air and breaks into fragments.
As the lava pieces fall back to the ground, they cool and harden into cinders (lava fragments about ½ inch in diameter) that pile up around the volcano's vent.
Cinder cones are the smallest volcanoes and are cone-shaped.

26. Where are volcanoes located
Where are volcanoes located? Volcanoes are found along destructive (subducting) plate boundaries, constructive (divergent) plate boundaries and at hot spots in the earth's surface.
What is the Ring of Fire? A volcanic chain surrounding the Pacific Ocean. It is formed along a destructive (subducting) plate boundary.
What are lahars and pyroclastic flows? The most destructive aspect of volcanoes are lahars and pyroclastic flows.
Lahars are volcanic mudflows created when water (from rain or melt water from glaciers) and ash mix. This deadly combination can have devastating results on the surrounding area. When lahars settle they can be metres thick and as hard as cement. Lahars can occur long after a volcanic eruption.
Pyroclastic flows are avalanches containing hot volcanic gases, ash and volcanic bombs. On steep volcanoes pyroclastic flows can reach speeds of over 100 miles per hour.