Theory
This scientist states that continents are moving slowly from their original location.
Who is Alfred Wegener?
This layer has been compared to the eggshell of a hard boiled egg, or the skin of an apple.
What is the lithosphere?
This super continent existed 250 years ago.
What is Pangaea?
Plates move away from one another at this boundary.
What is a divergent boundary?
This occurs when one tectonic plate slips under another.
What is subduction?
This theory was originally rejected because of lack of evidence.
What is continental drift theory?
As new seafloor moves away from an ocean ridge, it becomes (more,less) dense than the material beneath.
What is more?
Plates of the lithosphere float on this sphere.
What is the asthenosphere?
Plates will collide at this boundary.
What is a convergent boundary?
This occurs when the plates move away from a ridge.
What is ridge push?
Harry Hess explained why the continents are moving with this new theory.
What is the theory of plate tectonics?
Differences in this causes convection currents? (two answers)
temperature and density
A vast, underwater mountain chain is called...
What is an ocean ridge?
Plates move by one another at this boundary.
What is a transform boundary?
This occurs when a slab sinks and pulls the rest of the plate with force.
What is slab pull?
This underwater discovery helped Hess explain why the continents are moving.
What is sea-floor spreading?
Crust is neither destroyed nor formed at this type of boundary?
What is a transform boundary?
The youngest rocks on the ocean floor are located here.
What are mid-ocean ridges?
These currents beneath the lithosphere are responsible for the movement of continents.
What are convection currents?
This fossil fern helped Wegener determine that their was one super-continent.
What is the glossophteris?
These observations helped Wegener figure out that the continents were at one time joined together.
What are fossils, rocks and mountains, climate evidence and the way the continents seem to fit together?
These are most likely to form at convergent oceanic-continental boundaries.
What are active volcanoes?
Continental-continental plate collisions cause these.
What are tall mountain ranges?
When one plate collides and goes under another, it may melt and become part of this.
What is the asthenosphere?
The crust and upper mantle make up this sphere.
What is the lithosphere?