A powerful 4.8 magnitude earthquake struck northern New Jersey on Friday morning, rattling millions across the Northeast and triggering a series of unsettling aftershocks that continued to shake the region throughout the day and into the night.
The initial quake hit at around 10:23 a.m. ET, centered between the towns of Whitehouse Station, Califon, and Lebanon – a rural area about 60 miles northeast of Philadelphia and 50 miles west of New York City. While relatively shallow at just 3 miles deep, the moderate tremor packed enough punch to jolt residents from Long Island to Washington D.C., over 200 miles away.
“I was sitting at my dining room table and it just started shaking violently,” recalled Tim Apgar, fire chief in nearby Whitehouse Station. “I thought maybe a truck had backed right into the house. It rumbled and shook for a good 30 seconds or more, with the water in our pool visibly sloshing back and forth.”
Untypical Tremors for the Northeast
While not unheard of, earthquakes of this magnitude are quite rare in the Northeast region of the United States. The quake originated along the Ramapo Fault Line, an intraplate geological fracture that stretches from southeastern New York through northern New Jersey, eastern Pennsylvania and into Maryland.
Intraplate faults like the Ramapo are found within tectonic plates themselves rather than at their boundaries, where the majority of the world’s seismic activity occurs. With intraplate regions under less strain, earthquakes tend to be smaller but still very potent when they do strike due to the comparatively older, colder, and more rigid geology.
“An earthquake of this size can be considered strong for this region,” said Dr. Jessica Turner, a seismologist at Columbia University’s Lamont-Doherty Earth Observatory. “While nothing on the scale of major events along fault lines in the Pacific ‘Ring of Fire,’ a 4.8 magnitude quake is more than enough to cause localized damage, particularly to older structures not designed with quakes in mind.”
Striking at a Fault Sweet Spot
Indeed, the Ramapo Fault’s orientation and depth appeared to amplify the quake’s potency across a remarkably broad area. Preliminary data from the U.S. Geological Survey indicates the tremor was potentially felt by over 42 million people, with shaking reported as far north as Maine and as far south as Virginia.
New York City was definitely rattled, with office workers evacuating skyscrapers across Manhattan as a precaution. No major damage was reported in the city, though the quake certainly turned some heads.
“It felt like a huge truck went barreling down the street and crashed right into the building,” said Marissa Valdez, an accountant in Lower Manhattan. “Then it just kept shaking for what felt like forever. Things were swaying, pictures fell off walls. It was pretty scary, not going to lie.”
While startling, the upheaval was much more severe closer to the New Jersey epicenter. In the quaint borough of Lebanon, firefighters raced from call to call checking for any structural damage or emergencies. Miraculously, no injuries were reported despite the intensity.
“We got a couple gas leaks called in, along with a resident needing assistance and others just frantically asking if we felt the shaking too,” said Avery Schaefer, captain of the local EMS squad. “When the quake struck, our building swayed so violently, we thought for sure it was going to come down.”
Historic Gristmill Shattered by Shockwaves
While the region appeared to avoid any catastrophic destruction, at least one priceless piece of American history was not so lucky. The 18th century Colonel John Grist Mill in Whitehouse Station partially collapsed as the powerful seismic waves rippled through.
“This is one of the most important buildings from the Revolutionary War era,” said Adam Mueller, mayor of the local township. “To see the top portion crumble away into the road is just heartbreaking. But we’ll rebuild it accurately to its former glory – have to preserve these landmarks.”
Unsettling Pattern of Aftershocks
As if the initial tremor wasn’t distressing enough, a series of aftershocks began rippling through shortly after across northern New Jersey, southeastern Pennsylvania, and into New York City. The strongest – a 3.8 magnitude quake around 6 p.m. in Gladstone, NJ – gave the region an eerie repeat of the morning’s alarming shakes.
“I was just getting off work and suddenly everything started quaking again,” said Kennedy Duncan, a server at the Gladstone Tavern. “I was in disbelief, thinking ‘No way, not another one!'”
Aftershocks are essentially smaller earthquakes that occur in the same general area as the main shock, caused by lingering shifts along the reactivated fault line. The USGS warned such aftershock sequences can persist for weeks or even longer after a sizable quake.
“When you get an earthquake of this size, it’s not just one sudden jolt and done,” Dr. Turner explained. “Faults undergo a re-rupturing process that gradually relocates the built-up stresses, triggering more tremors in its wake. The 3.8 aftershock was substantial enough to be considered its own small earthquake.”
No Widespread Damage, But Unsettling All the Same
Fortunately, in the hours after the back-to-back quakes, no catastrophic damage or injuries were reported across the heavily populated Northeast corridor. Still, the unusual geologic event had millions on edge throughout the day, bracing for more potential shaking to come.
President Joe Biden was briefed on the situation and his administration continued monitoring for any major impacts. Mass transit agencies like New Jersey Transit were temporarily delayed as infrastructure inspections were conducted. Airports like Newark Liberty snarled with a morning of groaning steel and spooked passengers.
In Philadelphia, Mayor Cherelle Parker said the city’s municipal buildings appeared unscathed except for some preventative evacuations and procedural checks.
“Philadelphia has come through this rare earthquake in very good shape,” Parker told reporters. “But it’s certainly made for an unsettling day across our entire region.”
A ‘Once-in-a-Lifetime’ Wake-Up Call
For most Northeasterners, the 4.8 magnitude temblor and its restless aftershocks were an unprecedented and unnerving experience. The last similar earthquake to hit the area was back in 2011 when a 5.8 quake struck near Richmond, Virginia – still over 230 miles from Philly.
That vista-shaking 2011 quake ended up causing some damage in the Philadelphia region, including shattered glass at the city’s towering IBC building. Friday’s rumblings appeared to mercifully avoid any such widespread impacts.
But the alarming subterranean event was undoubtedly a wake-up call about the seismic risks lying beneath this ancient core of North America.
“I’ve lived in this area my whole life and certainly never felt anything like this morning’s earthquake,” said Whitehouse resident Will Melick, whose town lies right near the quake’s epicenter.
“It was pretty crazy, honestly,” Melick added. “I mean, you hear about California dealing with these all the time out west. But for us here in old, stable Jersey? It’s one of those things you never really imagine happening until suddenly it does. A bit of a once-in-a-lifetime event witnessing Mother Nature’s power like that.”
