Tectonics Hazards Flashcards
What are the four major layers of the Earth’s structure?
Crust, Mantle, Outer core and Inner core.
Which layer is the thickest?
Mantle.
Which two layers are entirely solid?
Inner core and Crust.
Which are the two different types of crust?
Oceanic crust and continental crust.
Which type of crust is more dense? Why is this significant?
Oceanic crust is more denser. This is significant because the oceanic crust then subducts under the continental because it is denser (in convergent plate boundaries).
What is the name of the process that causes Earth’s tectonic plates to move?
Convection currents.
How many different types of plate boundaries are there?
Four: Convergent, Collision, Divergent and Conservative.
What direction do the plates move in at Convergent plate boundaries?
The two plates (oceanic and continental) move towards each other and the denser on (oceanic) subducts underneath.
True or false? Volcanoes occur at conservative plate boundaries.
True, violent volcanoes occur at convergent plate boundaries.
Explain two characteristics of a shield volcano.
The type of lava (basaltic) is quite runny and that is because it has a lower silica content. The volcano erupts quite frequently and it is quite gentle when it does.
Explain two characteristics of a composite volcano.
The type of lava (andestic) is quite viscous and that is because it has a higher silica content. Since they don’t erupt that often when the do it is very harsh and violent.
What is a hotspot?
A hotspot is the place where magma rises up through the crust.
What does magnitude mean?
Magnitude the measure of earthquake size.
What is the name of the scale that earthquakes measure on?
The Richter scale.
What causes tsunamis?
An underwater earthquake which causes a large displacement of water.
