Section 8.1 What is an earthquake
focus
The point beneath Earth where an earthquake originates
true
True or False: it was not until the 1906 San Francisco earthquake was studied that the actual cause of earthquakes was understood
fault
a fracture in Earth along which movement has occurred
aftershock
a small earthquake that follows the main earthquake
about 100
how many major earthquakes take place each year
fault creep
slow gradual movement of a fault
elastic rebound
tendency for deformed rock along a fault to spring back to its original shape after an earthquake
elastic rebound
the ______________________________ hypothesis states that when rocks are deformed they bend and then break releasing stored energy
epicenter
the location on Earth's surface directly above the focus, or origin, of an earthquake
earthquake
the vibration of Earth produced by the rapid release of energy
true
true or false: most earthquakes occur along existing faults
seismic waves
vibrations that travel through Earth carrying the energy released during an earthquake
