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Vocabulary
Structure of the Earth
Continental Drift Theory
Plate Tectonics
Miscellaneous
100

This occurs when a plate moves over a magma plume in the ocean.

What is an island chain.

100

There are ______________ main layers of the Earth.

What is 3

100
Created the Continental Drift Theory
Who is Alfred Wegener
100
Earthquakes and Volcanoes are usually located in relation to these
What is a plate boundary
100
The Himalayan mountains are the result of a ___________________________ boundary.
What is convergent boundary
200
A number of rigid, but moving, pieces of Earth's surface
What is tectonic plates.
200
The thickest layer of the Earth
What is the mantle.
200
Evidence of matching animal fossils from two separate continents _____________________ and _____________________
What is Africa and South America
200
The mid-ocean ridge is an example of a ____________________ boundary and ___________________ occurs here where new ocean floor is formed.
What is divergent boundary; sea-floor spreading
200

Hot magma is less ________________ than cool magma, thus creating a convection cycle.

What is dense

300

The theory that all continents are fragments of Pangaea now drifting apart.

What is the Theory of Continental Drift

300

__________________ plates are more dense than _____________________ plates.

What is oceanic and continental

300
Evidence of tropical plants were found on this continent
What is Antarctica
300

Trenches are found only at

What is subduction zones.

300
_________________ are a result from the build up of stress at a plate boundary.
What is earthquakes
400

States that youngest rocks of ocean floor are at divergent boundaries, moving outward.

What is seafloor spreading.

400

This law explains why the Earth is not gaining or losing mass.

What is conservation of matter-the rocks are recycled.

400
Pangaea existed this many millions of years ago
What is around 250 million years ago
400

This is the mechanism (what causes) the plates to move.

What is convection (currents) cycles in the mantle

400
The San Andreas Fault in California is an example of a ____________________ boundary.
What is a transform boundary
500

This theory came after the Theory of Continental Drift once more evidence was discovered.

What is the Theory of Plate Tectonics

500
The Earth's crust is thinnest under the _____________________ and thickest under the _____________________.
What is thinnest under the ocean and thickest under the continents.
500

Continental Drift Theory was not accepted because it did not explain this

What is how the continents moved

500
The two types of convergent boundaries
What is subduction (where volcanoes often occur) and collision (where mountains are usually formed)
500

This person used sonar to map the bottom of the ocean and discovered the mid-ocean ridge in the Atlantic Ocean.

Who is Harry Hess!