Seafloor Spreading Vocab
What is a mid-ocean ridge?
A chain of underwater mountains where seafloor spreading happens.
Where can you find OLDER crust?
Closer or farther away from the mid-ocean ridge.
Farther away
What does converge mean?
To collide or come together
What are the three types of plate boundaries?
Divergent
Convergent
Transform
What are the two types of crust?
Continental crust
Oceanic crust
This is the process where old crust goes back into the mantle.
This process happens at a deep-ocean trench.
Subduction
Fill in the blank: When magma comes out of the mid-ocean ridge, it cools and becomes _________ crust.
New
This is where plates meet.
Hint: There are THREE types.
Boundary
Earthquakes will MOST often occur at which type of plate boundary?
Transform
Fill in the blank: Oceanic crust is _________ dense which means it will subduct back into the Mantle.
More
This land feature is the same as the mid-ocean ridge BUT it is on land.
Rift valley
What drives seafloor spreading?
What is a fault?
A crack or break in Earth's crust where plates move or slip past one another.
When TWO continental plates with EQUAL density collide, what will form?
A mountain range.
How many MAJOR plates are there on Earth?
7 (same as the continents)
What is the name of molten material that is in the mantle?
Magma
Fill in Ms. St. John's saying: "What happens on one side of the ridge __________________."
Happens on the other.
What are plates?
When oceanic crusts collides with continental crust, what will happen?
The oceanic crust will subject under the continental crust.
An ocean with MORE trenches will _________ and an ocean with LESS trenches will ___________.
Grow
This is a FORCE that pulls the older, denser crust into the mantle.
Gravity
The happen by the reversal or flipping of Earth's magnetic field.
What does diverge mean?
To pull apart, divide or move away from one another.
Show me the three hand movements to represent the plate boundaries.
----> <---- (convergent)
<---- ----> (divergent)
<----
----->
(transform)
Who was the woman who helped to create maps of the ocean floor using sonar?
Marie Tharp