Tectonics Flashcards
How do convection currents move tectonic plates?
The rising hot material, that is rising from the core cools down and becomes more dense so it sinks creating movement on the bottom of the tectonic plates and causes them to move.
How do earthquakes occur?
Earthquakes are caused by the tension that builds up at all three types of plate boundary
How does a composite volcano form?
A composite volcano forms at convergent boundaries. They form when a oceanic plate meets a continental plate, the denser oceanic plate is forced down into the mantle and destroyed. This often creates composite volcanoes.
How does a shield volcano form?
Shield volcanoes occur at hotspots. At a hotspot hot magma from the mantle moves towards the surface, causing an unusually large flow of heat from the mantle to the crust. Sometimes the magma breaks through the crust and reaches the surface, this causes an eruption and a shield volcano forms.
How does a tsunami occur?
Underwater earthquakes cause the seabed to move, which displaces water. Waves spread out from the epicentre of the earthquake (the point on the earths surface that’s straight above the focus).
