Earth's Layers
This is the thin, rocky outer layer of the Earth that we live on.
The Crust
Convection currents happen because _____ material rises and _____ material sinks.
Hot/Warm rises, Cold/Cool sinks
He was the scientist who first proposed the theory of Continental Drift.
Alfred Wegener
This is the underwater mountain range where new ocean floor is created.
Mid-Ocean Ridge
When two plates crash into each other, it is called a _____ boundary.
Convergent
This layer is made of solid iron and nickel and is the hottest part of the planet.
The Inner Core
In which layer of the Earth do convection currents flow?
The Mantle
This "Supercontinent" existed 250 million years ago before the continents broke apart.
Pangaea
Where would you find the oldest rocks on the ocean floor?
Farthest away from the ridge / near the continents
When two plates slide past each other, they often cause these natural disasters.
Earthquakes
The thickest layer of Earth, made of hot, semi-solid rock.
The Mantle
What is the "engine" or energy source that powers convection currents?
Heat from the core
Name two pieces of evidence Wegener used to prove his theory.
Fossils matching on different continents, "puzzle piece" fit of coastlines, or matching mountain ranges
This process happens when the ocean floor sinks back into the mantle at a deep-ocean trench.
Subduction
A Divergent boundary is most likely to create which feature?
A Rift Valley or Mid-Ocean Ridge
This liquid layer of metal creates Earth’s magnetic field.
The outer core
Describe the movement of a convection current in one sentence.
Heat makes rock less dense so it rises, then it cools and sinks back down in a circle.
Why did other scientists laugh at Wegener’s idea at first?
He couldn't explain how or why the continents moved.
What "pushes" the ocean floor apart at the ridge?
Magma rising up and cooling into new rock
The lithosphere is broken into giant pieces called _____.
Tectonic Plates