Plate Tectonics
Name the four parts of the Earth?
What are the two types of crust found on Earth?
Continental and oceanic.
What is the difference between magma and lava?
Magma is molten rock under the ground and lava is when it reaches the surface.
What is the name of the point in the Earth's crust where an earthquake is generated.
Focus
What causes a tsunami?
An underwater earthquake or landslide.
Name the two people who influenced the theory of plate tectonics.
Alfred Wegener and Harry Hess.
Name the type of plate boundary where two plates collide.
Convergent plate boundary.
Name a type of volcano.
One of: shield, cone or composite.
What is the name of the point on the Earth's surface above where the earthquake is generated?
Epicentre.
Outwards, like ripples in a pond.
What are two pieces of evidence that support the theory of continental drift?
Coastline matching up, same fossils on different continents, same geology on different continents, climate indicators.
Name the type of plate boundary where plates pull apart.
Divergent plate boundary.
Give two ways volcanoes can be dangerous.
E.g. lava flow, pyroclastic flow, ash clouds, landslides.
Name the three types of seismic waves.
P (primary) waves, S (secondary) waves and L (surface) waves.
How quickly could a tsunami affect land after an earthquake?
Less than an hour.
Describe the process of seafloor spreading.
Magma rises at mid-ocean ridges and solidifies, creating new crust. As more magma rises, it pushes the older crust further away from the mid-ocean ridge.
Name the type of plate boundary where plates move past each other.
Transform plate boundary.
Where are most of the world's volcanoes found, and why?
They are found on the ring of fire because this is a lot of plate boundaries occur.
Which type of seismic wave would arrive first?
P waves.
Is Australia at risk from tsunamis?
Yes, but the risk is small because Australia is located away from plate boundaries where the underwater earthquakes are likely to occur.
Name two processes that cause tectonic plates to move.
Two of: convection currents, downwards pull of oceanic crust, upwards movement of magma at ocean ridges.
If continental and oceanic crust collide, what will happen and why?
The oceanic crust will subduct under the continental crust because it is more dense.
How are volcanic chains created?
Magma plumes erupt from fixed hotspots in the Earth and form volcanoes. As a tectonic plate moves, it moves across this hotspot so new volcanoes form in a chain behind the moving plate.
On a seismogram, the distance between the P waves and S waves tells you what?
How far away the earthquake is.
How can you stay safe during a tsunami?
Move away from the beach, get to high ground or go inland, know your evacuation route, remember there might be more than one wave.