Understanding earthquakes

Created by

Lucas B

Cards (15)

How are earthquakes caused?
When tectonic plates move against each other at tectonic plate boundaries, they stick and huge amounts of pressure build up, until the rock fractures and energy is released as seismic waves
What is the earthquake focus?
The point inside the crust from where the pressure is released
What is the earthquake epicentre?
The point on the surface directly above the focus
What are primary seismic waves?
The first seismic waves released from an earthquake, which travel along the focus
What are secondary seismic waves?
The second seismic waves released from an earthquake, which travel along the focus
What are Love waves?
The third seismic waves released from an earthquake, which travel along the surface
What are the characteristics of primary waves?
They are the fastest and first to reach the surface, travel through both solids and liquids, but are less destructive
What are the characteristics of secondary waves?
They are slower than primary waves, only travel through solids, but are more destructive
What are the characteristics of Love waves?
They are the slowest and last to reach the surface, but are the most destructive seismic waves
How can seismic waves be measured?
Using a seismometer, which detects and measures ground movements
What is magnitude?
The amount of energy released by an earthquake in the epicentre, measured by the Moment Magnitude Scale
What are the primary effects of earthquakes?
Ground shaking which causes buildings and infrastructure to collapse, and cracks in the Earth's crust from the energy released during an earthquake
What are the secondary effects of earthquakes?
Liquefaction where the shaking from the earthquake causes the ground to melt, landslides also occuring from shaking, and tsunamis caused by underwater earthquakes
What are aftershocks?
Generally smaller earthquakes that occur after a major one
What is intensity?
An earthquake's effect on people, infrastructure, and the environment