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Related to foreshock: tsunami, aftershock


A minor tremor of the earth that precedes a larger earthquake originating at approximately the same location.


(Geological Science) a relatively small earthquake heralding the arrival of a much larger one. Some large earthquakes are preceded by a series of foreshocks. Compare aftershock


(ˈfɔrˌʃɒk, ˈfoʊr-)

a relatively small earthquake that precedes a greater one by a few days or weeks and originates at or near the focus of the larger earthquake.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.foreshock - a tremor preceding an earthquake
earth tremor, microseism, tremor - a small earthquake
References in periodicals archive ?
0 quake was a foreshock of an even bigger earthquake, Chen replied, "It can't be ruled out, however the probability is relatively small.
All aftershocks and foreshock should be eliminated from the catalogues (Abrahamson, 2006).
The study, based on data gathered by NASA satellites, details observations of particles being accelerated in the foreshock region - which lies just beyond Earth's magnetic field - as a result of some hitherto unknown mechanism.
Let's hope this is not a foreshock of something bigger to come, which is certainly a possibility," said Dan Jaksa, senior seismologist for GeoScience in Australia.
0 foreshock occurred in close proximity to active fluid injection wells.
Dan responded correctly only to the untaught prefixed words forethought (session 6), foresight (session 9), and forethought and foreshock (session 15) after root word training.
5-magnitude foreshock, rose to 45 as of Tuesday, while search and rescue operations continued amid strong aftershocks.
The agency also said that Saturday's massive earthquake was the main event while the one on April 14 was a foreshock.
Even if a foreshock occurs, there is no means to identify whether it is actually a aACAyforeshock' and that a major quake will follow.
After performing required revisions, including deleting aftershock and foreshock through spatial and temporal windows method [8], homogenization of magnitudes, determination of year, completion of catalogue and etc.
If an aftershock is larger than the main shock, the aftershock is redesignated as the main shock and the original main shock is redesignated as a foreshock.
Conditions in the foreshock change in response to solar particles streaming in from the sun, moving magnetic fields and a host of waves, some fast, some slow, sweeping through the region.