foreshocks
Quakes before quakes
Foreshocks are smaller earthquakes that precede a larger seismic event in the same area, though they can only be identified as such after the main quake occurs.
Seismologists study foreshock patterns hoping to improve earthquake prediction, with limited success.
The term extends metaphorically to warning signs before any major disruption: The market volatility proved to be foreshocks of the coming crash.
Slight shaking movements
- magnitudeSize or scale
- epicenterPoint above seismic origin
- faultImperfection or blame
- seismographEarthquake measuring device
tectonics · P-waves · S-waves · hypocenter · seismicity · rupture · subduction · seismometer
Alert about danger
- harbingerOne who foreshadows
- indicatorSign revealing status
- signalMessage-conveying cue
- forewarningNotice of future trouble
prelude · herald · portent · omen · antecedent · forerunner · presage · precursor
tremors
Slight shaking movements
seismograph · tectonics · P-waves · S-waves · hypocenter · seismicity · rupture · subduction · seismometer · vibrations
warning
Alert about danger
forewarning · prelude · herald · portent · omen · antecedent · forerunner · presage · precursor · early-warning
alert
Warning or watchfulness
- evacuationRemoval from danger
- emergencySerious sudden danger
- readinessState of being prepared
drill · safety · advisory · notification · siren · alarm · hazard · risk · escape · survival
- earthquakesearthquake, quake, earthquakes, quakes, epicenter
- seismologyearthquake, earthquakes, seismograph, seismicity, seismometer