Earth's Layers
This is the science that studies Earth.
What is Geology?
A break or a fracture in rock where movement has occurred
What is a fault?
This sudden shaking of the ground can result from movement of rocks beneath Earth's surface
What is an earthquake?
This instrument records vibrations caused by earthquakes
What is a seismograph?
This opening or crack in Earth's surface can release hot gases, ash, and molten rock
What is a volcano?
The Earth's three major layers from the outside inward
What are the crust, mantle, and core?
In this type of fault, rocks on one side move down while rocks on the other side don't move
What is a normal fault?
This point on Earth's surface is directly above the place where an earthquake begins
What is the epicenter?
This is the record produced by a seismograph during an earthquake
What is a seismogram?
This is the channel through which volcanic gases, ash, and rock are ejected
What is a vent?
This solid outer layer is the only major layer directly observed and sampled
What is the crust?
In this type of fault, rocks on one side move horizontally along the fault
What is a strike-slip fault?
This weak earthquake may be followed by smaller aftershocks
What is a tremor?
These push-pull waves, also called P waves, travel in the same direction as the wave motion and pass through solids and liquids
What are primary waves?
This term describes a volcano that could erupt again but is not currently active
What is a dormant volcano?
This elements makes up 47% of the Earth's crust by weight
What is oxygen?
These mountains form when layers of rock buckle as tectonic plates push together
What are folded mountains?
This branch of science studies earthquakes
What is seismology?
These waves consist of side to side motions and can only travel through solid regions of the Earth's interior
What are secondary waves?
This belt around the Pacific Ocean contains more than half of the world's active volcanoes
What is the circum-Pacific belt, or the Ring of Fire?
This is the hot, mostly solid middle layer
What is the mantle?
These mountains form along a fault when rocks on one side move up and rocks on the other side sink
What are fault-block mountains?
This theory explains how strained rocks on either side of a fault suddenly spring back, causing vibrations in the Earth's crust
What is the elastic rebound theory?
This famous scale, named after the man who invented it, is used to measure earthquake strength
What is the Richter scale?
This fast-moving, superheated mixture of gas and volcanic ash races down a volcano's slope as an avalanche
What is a pyroclastic flow?