UPDATE: 11 more overnight aftershocks rattle N.J. after 4.8 magnitude earthquake
Earthquakes are very tough to predict, but people in the New Jersey region may want to prepare themselves for some more sudden shaking and rumbling in the wake of Friday morning’s magnitude 4.8 quake — one of the largest earthquakes to hit the state in more than a century.
Experts from the U.S. Geological Survey say there’s nearly an 80% chance our region will be hit with an aftershock of magnitude 3.0 or higher within the next week and almost a 15% chance of an aftershock that’s magnitude 4.0 or stronger.
That means the Garden State, and nearby states, could be in for more startling jolts, rattling windows and loud vibrations similar to what occurred Friday morning.
“Aftershocks are earthquakes,” a spokesperson for the USGS told Newsweek. “They are just smaller magnitude quakes that follow the largest quake, which is referred to as the ‘mainshock.’ The M4.8 (Friday) morning would be considered the ‘mainshock’ since it was the largest, while the M4.0 and others occurring after are called ‘aftershocks.’”
“If a larger earthquake were to occur after the mainshock, then that new quake becomes the mainshock, and the earlier quakes become ‘foreshocks,’” the spokesman added. “Then things start again as subsequent smaller quakes following that new quake become aftershocks.”
Almost a dozen aftershocks occurred in New Jersey from late Friday morning through Friday evening, ranging from magnitude 1.8 to magnitude 4.0. Although they were centered in Hunterdon, Morris and Somerset counties, some of them sent shockwaves through the ground for hundreds of miles — causing scores of homes and other structures in many states to shake.
The 4.0 aftershock, which occurred shortly before 6 p.m. Friday, was felt by people as far north as Connecticut and Massachusetts, as far south as Maryland and as far east as eastern Long Island, New York, according to public reports submitted to the U.S. Geological Survey.
“Earthquakes will keep coming, but we can’t predict them,” Allan Rubin, a professor and seismologist at Princeton University, told News 12 New Jersey in an interview that aired Friday evening. “Undoubtedly, in my mind, there will be an earthquake this size (like Friday morning’s quake) in the future, but we don’t know if it’s gonna come in 100 years or 50 years or maybe tomorrow.”
One thing Rubin does know is Friday’s initial quake was a substantial one, especially for the New Jersey region.
“This was a big surprise to me,” Rubin said. “I spent some time in California, and I’d say this is the strongest ground shaking I’ve felt in any earthquake.”
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Len Melisurgo may be reached at LMelisurgo@njadvancemedia.com or on X at @LensReality.
