[grayt urth·kwayk] An earthquake with a magnitude of 8 or greater on the Richter Scale!

[mai·krow·urth·kwayk] An earthquake with a magnitude of 2 or less on the Richter scale. These earthquakes usually can't even be felt!...

[rik·ter skayl] A numerical scale that is used find out the magnitude of an earthquake through seismograph oscillations (ups and downs in...