The lower part of this is under such pressure that it is solid, even though it is at such a high temperature.
What is the core.
100
In 1912, what scientist proposed the idea of continental drift to explain why continents seem to fit together like a jigsaw puzzle?
Who is Alfred Wegener.
100
What is the place where two plates meet?
What is a plate boundary.
100
These are caused by the sudden shifting of rock as plates shift positions.
What are earthquakes.
200
Most of the Earth’s mass is made up of what layer?
What is the mantle.
200
What were the three pieces of evidence that supported Wegener’s theory?
What is fossils, seafloor spreading, and convection.
200
Many earthquakes occur in southern California because of a large __________, or break in the crust.
What is a fault.
200
These occur where magma from the mantle either flows or explodes through the crust.
What are volcanoes.
300
What is the part of the Earth that we live on?
What is the crust.
300
When a liquid is heated, it becomes less dense. It rises and floats above cooler liquids. When it cools again, it sinks. More hot liquid can float above it. This process is called what?
What is convection.
300
When plates move away from each other, seafloor spreading and the forming of valleys can occur. This is called what?
What is a spreading boundary.
300
Believe it or not, most of these are located on the ocean floor.
What are volcanoes.
400
Earth’s crust and part of the upper mantle make up which layer?
What is the lithosphere.
400
Scientists believe that convection in the mantle can move what?
What is Earth's tectonic plates.
400
When plates slide past each other, strong earthquakes can occur. This is called what?
What is a fracture boundary.
400
These detect ground movement (earthquakes) as they occur.
What are seismographs.
500
What theory explains how the lithosphere is broken into moving plates that float on a layer of partly melted rock?
What is plate tectonics.
500
Alfred Wegener thought that about 225 million years ago, the continents were joined in one large continent he called Pangaea. What does Pangaea mean?
What is "all earth".
500
When plates collide, one plate might slide beneath the other. As a result, towering mountains can form. Sometimes, deep ocean trenches, earthquakes, and volcanoes can result. This is called what?
What is a colliding boundary.
500
Which U.S. state is considered a hot spot because of the number of volcanoes there?