Seafloor Spreading
What is seafloor spreading?
Tectonic plates separating from each other.
Who was the scientist that discovered the theory of continental drift?
Alfred Wegener
Continents were once together.
*bonus points for students who mention Pangea*
The Crust is _________ km below Earth's Surface.
40 km.
Mid-Atlantic Ridge
An underwater mountain range formed by upwelling magma at a divergent boundary.
How fast is the Mid-Atlantic Ridge spreading per year?
A few inches
T/F: Reverse Polarity is a very common occurrence that happens often.
False; it is rare.
Which layer is a solid metal ball made of mostly nickel and iron?
Inner Layer
The Mantle is _________ km below Earth's Surface.
2,800 km
The process where one tectonic plate moves under another and sinks into the mantle.
Yes or No:
Does seafloor spreading have to do with the continents moving?
Yes!
What is an undersea mountain chain where new ocean floor is produced is ________?
Mid-Ocean Ridge
Which layer is mostly composed of liquid nickel and iron?
Outer Layer
The Outer Core is _________ km below Earth's Surface.
5,200 km
Divergent Boundary
A tectonic plate boundary where two plates move away from each other.
What type of rock forms when magma cools underwater?
Igneous rock
What does Pangea mean?
Supercontinent or All the present continents joined together or Greek for “All the Earth.”
What is the theory that explains how new crust is created at mid-ocean ridges?
Seafloor Spreading
The Inner Core is _________ km below Earth's Surface.
6,400 km
Convergent Boundary
A tectonic plate boundary where two plates move toward each other.
What is something that can be found on the Mid-Atlantic Ridge?
Volcanoes
Either: Fossils, Geologic, Climate.
New ocean crust is continually formed at ___________?
Mid-Ocean Ridges
What were the two Continents Alfred Wegener first noticed would fit together?
South America and Africa.
Transform Boundary
A tectonic plate boundary where two plates slide past each other horizontally.