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List the four layers of Earth (from the outer layer to the inner layer).
Crust, mantle, outer core, inner core
Which layer of the Earth is the thickest because it makes up 84% of Earth's volume?
Mantle
As you go deeper inside the Earth, what happens to the heat, density, and pressure?
All three increase as you get closer to the core.
Which two layers of Earth are made of hard, solid material that does not flow?
Crust & inner core
Which layer of Earth is the only liquid layer, made of melted iron and nickel?
Outer core
Which layer of Earth is the hottest?
Inner core
What caused the Earth to form in layers?
Density
How do differences in density affect the movement of materials?
Heavier material sinks, lighter material floats.
What theory did Alfred Wegener propose in 1912 to explain the position of the continents?
Continental Drift
Harry Hess proved Wegener's theory by discovering new crust being made at divergent boundaries on the sea floor. What did Hess call his theory?
Seafloor Spreading
A combination of Wegener's and Hess' theories produced the commonly accepted belief that the lithosphere is divided into plates, which move on top of the asthenosphere. What is this modern theory called?
Plate Tectonics
Which type of boundary results in the subduction of a plate and volcanic activity on Earth's surface?
Convergent boundaries (oceanic-continental)
Which two geologic events are MOST common along tectonic plate boundaries?
Earthquakes & volcanoes
Which geological feature is formed at a convergent boundary between two continental plates?
Mountains
What are the cracks in Earth's crust caused by pressure between the plates?
Faults
Which geologic event is the result of earthquakes in the sea floor?
Tsunamis
