abstract
amplitude
background
beat
break
change
curve
digital
disaster
display
earthquake
electric
electricity
electronic
emergency
eruption
fracture
frequency
graph
grid
illustration
meter
monitor
motion
natural
nature
oscilloscope
physical
pressure
pulse
pulsing
quake
rate
richter
richter scale graph
scale
scary
seismic
seismograph
seismometer
sharp
symbol
technology
trace
wave
waveform