Unit 8 Lesson 3 Flashcards
How many layers does Earth have?
Earth has 4 layers
Crust
The thin, rigid, rocky outer layer
Mantle
The thickest layer
Some liquid rock but Mostly solid
Outer Core
Molten liquid metal
Extremely hot
Inner Core
Made of solid iron and nickel
Plate tectonics
Earth’s crust is divided into plates that are always moving
Tectonic plates move toward each other and away from each other
Fault
A break in earth’s crust where rock on one side can move in relation to rock on the other side
Earthquake
When the pressure becomes too great, the rock on one side of the fault snaps free and slides past the rock on the other side
The release of energy and shaking of the ground
Focus
The point inside earth where an earthquake begins
Epicenter
The point on earth’s surface directly above the focus.
Earthquake motion is most severe here
Seismograph
A device that graphs earthquakes. Can use it to predict if an earthquake is likely to occur
Earthquake magnitude
The amount of energy it releases
How strong the earthquake is
Richter Scale
Measures the magnitude of earthquakes on a scale of 1 - 10 Using a seismograph
Moment Magnitude Scale (MMS)
Uses a mathematical formula to calculate the total energy an earthquake releases
More accurate than the Richter Scale
Magma
The liquid rock below earth’s crust
