Key Terms
People, Places, and Things
True or False
Mapping the Ocean Floor
Theory
100
The hypothesis that the continents slowly move across Earth's surface.
What is Continental Drift?
100
A young German scientist that proposed the theory of continental drift.
Who is Alfred Wegener?
100
True or False: The Pacific Ocean is shrinking.
True.
100
A device used to determine the distance to objects under water; used to map the mid-ocean ridge.
What is sonar?
100
Wegener's name for his supercontinent.
What is Pangaea?
200
The process by which molten material adds new oceanic crust to the ocean floor.
What is Sea-Floor Spreading?
200
An American geologist that proposed Sea-Floor Spreading.
Who is Harry Hess?
200
True or False: At deep-ocean trenches, conduction allows oceanic crust to sink back into the mantle.
False.
200
The longest chain of mountains in the world.
What is the mid-ocean ridge?
200
Wegener used evidence from landforms, climate, and these to support his theory of continental drift.
What are fossils?
300
A trace of an ancient organism that has been preserved in rock.
What is a fossil?
300
The name of the single landmass that broke apart 200 million years ago and gave rise to today's continents.
What is Pangaea?
300
True or False: The Earth's magnetic field has changed direction over time.
True.
300
In relation to the mid-ocean ridge, oldest rock is located here.
What is farther away from the ridge?
300
Wegener believed that these were formed when drifting continents collided causing the edges to crumple and fold.
What are mountains?
400
The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle
What is subduction?
400
The undersea mountain chain where new ocean floor is produced.
What is the mid-ocean ridge?
400
True or False: The geographic north pole is at the same exact location as the magnetic north pole.
False.
400
In relation to the mid-ocean ridge, youngest rock is located here.
What is in the center of the mid-ocean ridge?
400
True or False: Wegener believed that Earth's climate had changed over time.
False.
500
A device that determines the distance of an object under water by recording echoes of sound waves.
What is sonar?
500
A deep valley along the ocean floor through which oceanic crust slowly sinks towards the mantle.
What is a deep-ocean trench?
500
True or False: The Atlantic Ocean is expanding.
True.
500
Molten material, drilling samples, and magnetic stripes are used as evidence that this process occurs.
What is Sea-Floor Spreading?
500
The name given to the group of geologists that opposed Wegener's theory of continental drift.
What are the Fixists?
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