The aftershock, reported around 6 p.m., had a 3.8 magnitude and was centered near Gladstone, New Jersey, the United States Geological Survey said. The aftershock was initially said to be 4.0 magnitude.
[Ads /]
Residents recall aftershock hours after 4.8 earthquake in NJ
There have been several aftershocks throughout the day following the original 4.8 earthquake, which happened around 10:23 a.m. and centered between the towns of Whitehouse Station, Califon and Lebanon. That area is about 60 miles northeast of Philadelphia.
READ MORE: USGS weighs in on NJ earthquake, how animals may be able to sense them earlier
Aftershocks will continue for days and weeks ahead, the USGS said.
The Friday morning quake startled millions of people in a region of the country unaccustomed to such tremors.
The 4.8 magnitude registered by this earthquake is just below what's considered to be a moderate quake.
The earthquake had a depth of about three miles, the USGS said.
The agency's figures indicated that over 42 million people might have felt the rumbling.
READ MORE: Viewer videos capture the moment a 4.8 magnitude earthquake shook the region
There are an estimated 13,000 earthquakes in the 4.0 - 4.9 range worldwide every year, according to a chart from Penn State University.
It originated near the Ramapo Fault Line, which extends from near the Hudson River in southeastern New York to just south of Harrisburg, Pennsylvania.
Rattling near the epicenter
Officers in Tewksbury and Lebanon townships spent the day responding to several calls near the center of the quake.
Chopper 6 was overhead as firefighters traveled around town to assess any damage.
"It's pretty crazy. I thought someone ran into the building with a forklift," recalled Will Melick, an employee at Melick's Town Farm.
"I was in disbelief after, like was that really an earthquake," added Kennedy Duncan, an employee at Gladstone Tavern.
Hunterdon County officials say thankfully there have been no injuries.
[Ads /]
As for damages, they say an assessment is underway. So far there have only been reports of structural issues on private properties.
Residents and business owners are urged to document their damages online.
Historic site in New Jersey damaged by quake
Action News was in Whitehouse Station, New Jersey shortly after the quake and caught up with emergency responders in between calls.
RELATED: New Jersey earthquake measured on Penn State Brandywine's seismometer
"I was sitting at the dining room table. I thought someone backed into our house, it just started to shake," said Whitehouse Fire Company Chief Tim Apgar. "It went on for a good 30-plus seconds, just rumbling and shaking. The water in our built-in pool was going back and forth like someone was surfing."
EMS crews staffed for the day felt their building sway, then began responding to calls.
4.8 magnitude earthquake hits NJ, shaking felt across Northeast including Philadelphia area
"We got two gas leaks, a resident for a lift assist, and we had someone call into the station asking if we felt what they felt," said EMS Captain Avery Schaefer.
The damage in the area was minimal, but not every building escaped unscathed. An important piece of New Jersey's history was damaged in the quake.
"This is the Col. John Grist Mill," Mayor Adam Mueller said as he walked Action News reporter Annie McCormick around the site. "It was constructed around 1760 and it was an integral part of the American Revolution."
He said the top portion of the structure collapsed.
"It was in the roadway," Mueller said. "I imagine all these rocks and stones will be replaced historically accurately, to its former glory."
READ MORE: Earthquake scale: How they are measured and what the magnitude and intensity scales mean
New Jersey Gov. Phil Murphy said there is only "limited damage" across the state.
Meanwhile, in Philadelphia, Mayor Cherelle Parker said no damage has been found at the city's municipal complex, and no injuries were reported.
"The city has come through this earthquake in very good shape," Parker said.
Earthquake centered in New Jersey felt by people in Center City Philadelphia
President Joe Biden was also briefed on the earthquake and his team is monitoring potential impacts, according to White House officials.
Some local mass transit agencies had delays after the quake while inspections were performed, but things are now on or close to schedule.
[Ads /]
Earthquake rattles New York City, felt in Washington, D.C.
The quake also rattled New York City, but officials there say there have been no major impacts.
The earthquake could be felt as far south as Washington, D.C. and as far north as Maine, according to the U.S. Geological Survey.
While there were no immediate reports of serious damage, officials were checking bridges and other major infrastructure.
An earthquake centered between NYC and Philadelphia rattles much of the Northeast
Earthquake felt in Philadelphia back in 2011
The last time people felt an earthquake this strong in Philadelphia was back in August of 2011.
That's when a 5.8 magnitude earthquake struck near Richmond, Virginia.
Even though that's 230 miles away from Philadelphia, it was clearly felt here and even caused damage.
In Center City, it shattered a pane of glass on the Independence Blue Cross building. Hundreds of people inside filed into the streets.
The same was the case at Citizens Bank Park in South Philadelphia where Phillies fans rushed out of the stadium. Ultimately, that night's game still went on.
Viewer videos capture the moment a 4.8 magnitude earthquake shook the region
What causes an earthquake?
Earthquakes are violent shaking from the planet's surface, according to AccuWeather. They're caused by movement from Earth's outermost layer, the crust.
The crust is broken up into pieces called tectonic plates that are always on the move, though usually in ways we cannot feel.
When the plates hit a roadblock, stress builds and leads to cracks in the Earth called faults.
In time, the energy from within builds to the breaking point. That sudden release leads to an earthquake.
The shaking begins at a central region called the epicenter and spreads far and wide. An earthquake can then be followed by additional shaking known as an aftershock.
What to do after an earthquake
Here are some tips for what to do after an earthquake hits:
- First, check on yourself on those around you to make sure everyone is okay.
- Check water, gas and electric lines for damage
- If any lines are damaged, shut them off if you can
- Be alert for more shaking as aftershocks are common after earthquakes