Foreshocks

There December what's called foreshocks, waiting for a largest quake about one hour or less later. ❋ Unknown (2010)

A typical large earthquake will include a mainshock, the largest earthquake in a sequence, and may be preceded by smaller earthquakes known as foreshocks and followed by smaller earthquakes called aftershocks. ❋ Unknown (2004)

In April 2009 a major earthquake in Italy was preceded by a series of small earthquakes, known as foreshocks, but that doesn't always mean a big one is coming. ❋ Unknown (2010)

One such sign is a pattern of small "foreshocks" that leads to a major shock. ❋ Unknown (1981)

Occasionally there will be foreshocks, but unfortunately, we never really know when a smaller earthquake is a foreshock and when it isn't, and as far as I know we really didn't have any particular warning for this earthquake. ❋ Unknown (2010)

According to local authorities, a significant number of foreshocks smaller seismic events preceding a large event had been experienced in the region prior to the main shock. ❋ Unknown (2009)

One of the things we find about foreshocks is that they happen within 10 kilometers of their main shock. ❋ Unknown (2007)

Sometimes there are foreshocks, but there are no geological clues offered here. ❋ Unknown (2005)

It apparently occurred without any significant foreshocks. ❋ Unknown (2003)

( "The problem is distinguishing between those and other patterns that don't turn out to be foreshocks, because no large earthquake follows them," says Karen McNally, another of Caltech's geophysicists.) ❋ Unknown (1981)

The earthquake was preceded by foreshocks, including a 7.2 magnitude earthquake that occurred two days earlier, about 25 miles away. ❋ Unknown (2011)

Not all massive earthquakes give warning shots like foreshocks, and even when they do, those may only be identified as precursors to something bigger in hindsight. ❋ Unknown (2011)

On the morning of Feb. 4, 1975, a swarm of foreshocks led officials in Haicheng, China, to predict an earthquake and issue evacuation orders. ❋ JERRY THOMPSON (2011)

They were to decide whether the small tremors in the quake-prone zone were foreshocks leading up to a larger quake, and what the public should be told. ❋ JERRY THOMPSON (2011)

Despite the massive foreshocks, there was no way to predict that Japan's biggest-recorded earthquake was looming, said Paul Caruso, a geophysicist with the U.S. Geological Survey USGS in Golden, Colo. ❋ Unknown (2011)

Today's earthquake was preceded by a series of large foreshocks over the previous two days, beginning on March 9 with a magnitude 7.2 quake about 25 miles 40 km away, and continuing with three other earthquakes greater than magnitude 6, according to the USGS. ❋ Unknown (2011)