Tectonic Plate Theory
Who proposed the original idea of continental drift in 1912?
Alfred Wegener
What are the three major types of plate boundaries?
Divergent
Convergent
Transform
What natural disaster is most commonly associated with transform plate boundaries?
Earthquakes
What is the term for the process where one plate sinks beneath another?
Subduction
What is one type of evidence that Wegener used to support continental drift?
Fossils
Jigsaw Coastlines
Magnetic Stripes on the Sea Floor
At which boundary type do tectonic plates move away from each other?
Divergent
What is the “Ring of Fire”?
A zone of frequent earthquakes and volcanoes around the edges of the Pacific Plate.
Why are oceanic plates generally subducted under continental plates?
Oceanic crust is denser and thinner than continental crust.
What process inside the mantle is responsible for moving tectonic plates?
Convection currents
Why are volcanoes common at convergent boundaries but rare at transform boundaries?
Transform boundaries slide past each other, not allowing magma to rise.
Which plate is responsible for the “Ring of Fire”?
The Pacific Plate
Why are volcanoes uncommon at transform boundaries?
Plates slide past each other without creating space for magma to rise.
What discovery about rocks on the ocean floor helped prove that new crust forms at mid-ocean ridges?
There was magnetic patterns matching on either side of the mid-ocean ridge and rocks closer to the ridge are younger than rocks farther away.
Which boundary type is most strongly associated with deep ocean trenches?
Convergent (subduction zones)
At which type of boundary does new crust form?
Divergent boundaries (mid-ocean ridges)
Which three forces influence the speed of tectonic plate movement?
Ridge push
Slab pull
Convection currents.
How can Earth’s crust be both constantly created and constantly destroyed at the same time?
New crust forms at divergent boundaries through seafloor spreading, while old crust is destroyed at convergent boundaries when it sinks back into the mantle through subduction.
At a convergent boundary between two continental plates, what major geological feature is most likely to form?
Mountains
Why do tsunami waves increase dramatically in height when they approach shallow coastal waters, despite being barely noticeable in deep ocean?
As the wave enters shallow water, its speed decreases and wavelength shortens, forcing the energy upward into a much taller, more destructive wave.
What does the pattern of increasingly older volcanic islands as you move away from a hotspot indicate about the plate above it?
The plate is moving over a stationary hotspot, and the age progression shows both the speed and direction of plate movement.