Evidence of Plate Motion
Wegener developed the hypothesis that Earth's landmasses had once been fused together, and then slowly broke apart in a process called what?
Continental Drift
What is formed when two tectonic plates collide at a convergent boundary?
The type of stress that pulls on and thins an area of Earth's crust is called what?
tension
Most volcanoes occur at hot spots?
True/False?
False, most volcanoes are formed at or near convergent and divergent boundaries.
The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent boundary.
What is subduction?
Wegener believed there once was a supercontinent called what?
Pangaea
What is the circular movement of material in the mantle that drives plate movement called?
Convection
When a plate is compressed it can create what?
mountains
True or False
True
An area where magma from deep within the mantle melts through the crust above.
Hot Spot
Evidence that supported the hypothesis of continental drift included fossils, land features, and what?
Plates move apart from each other at a ________________ boundary.
Seismic waves produced by earthquakes are measured by a device called what?
seismographs
Once magma touches oxygen or water is becomes ______________?
Lava
Single number that geologists use to assign to an earthquakes size
magnitude
The zipper-like mountain ranges that run across the floors of the ocean are called what?
mid-ocean ridges
Earthquakes often occur along ______________________ as a result of the buildup of stress.
plate boundaries
Which side of the United States is at greater risk of having an earthquake? Why?
West Coast because of the San Andres Fault
Describe the magma in an explosive eruption.
The magma will be thick and sticky causing build up.
Name 3 types of faults
1. Normal Fault
2. Reverse Fault
3. Strike-Slip Fault
The process where molten rock flows up through a crack in Earth's crust and hardens into solid strips of new rock on both sides of the crack is known as what?
Sea-Floor Spreading
A construction company wants to build a new highway over a transform boundary. Is this a good idea? Why or why not?
No. Plates move in opposite directions at transform boundaries. Any structure that is built on or near such boundary could be cut in half, offset, or otherwise damaged.
You hear about an 8.0 magnitude earthquake on the news. Bonnie says "That doesn't sound too bad. An 8.0 is just one more than the 7.0 we had here last year." Explain why that's not the right way to think about the magnitude of an earthquake.
Every whole number step on the scale isn't just "one more," it's actually 32x increase in released energy.
Name 3 ways we can predict a volcano eruption.
2. Tiltmeter - measure the tilt of the volcano
3. Seismograph - measure the rumblings deep inside the volcano
What did a tectonic plate say to another tectonic plate after they accidentally collided?
My fault!
:)