By now we’re all aware of Friday’s 4.8 magnitude earthquake that historically rattled New York City. The quake officially centered near Lebanon, New Jersey according to the U.S. Geological Survey, with ripples being felt as far as Philadelphia and Boston.
With the original shake behind us now, many have wondered about possible aftershocks of Friday’s seismic event, and we’re here to answer your questions.
What are aftershocks after an earthquake?
Aftershocks are smaller, lower magnitude earthquakes that occur in the same area as the main earthquake. They are caused by the Earth’s crust trying to readjustment stress after the main earthquake’s massive release of energy. This phenomenon will typically be about 1.2 magnitude units smaller than the mainshock.
These aftershocks can range in magnitude and frequency as well, with some being barely noticeable and some damaging.
How long can aftershocks happen after an earthquake?
Aftershocks can occur minutes, hours, days, or even weeks after the main earthquake, gradually decreasing in frequency and intensity over time. There’s no set rule on how long they will last, and is often based on factors such as the size of the initial earthquake, geological characteristics of the area, and more.
Will there be any aftershocks from Friday’s earthquake?
Possibly! As mentioned, aftershocks can happen in the weeks after the initial event. Dax Soule, a seismologist and assistant professor at Queens College told CBS New York, “While aftershocks are a concern for this first 24, 36, 72-hour period out to about a week, the entire East Coast is a seismically active area. But most of the earthquakes are relatively small.”
A few aftershocks have already been felt in NYC and New Jersey which you can see below, but the possibility of even more aftershocks as of now [Tuesday afternoon] is currently in the air.
How many aftershocks have happened in NY, NJ since 4.8-magnitude quake?
According to information released by Governor Kathy Hochul, there have been just over 30 aftershocks felt around the region as of Saturday morning. One of the stronger ones was felt at around 5:30 pm on Friday. See below for a running list of aftershocks recorded in the NJ/NY region.
| 2024-04-06T04:18:26.965EST | 1.9 | 4 km E of Califon, New Jersey |
| 2024-04-06T04:09:18.260EST | 1.7 | 6 km ESE of Califon, New Jersey |
| 2024-04-06T03:11:18.616EST | 1.7 | 4 km WSW of Bedminster, New Jersey |
| 2024-04-06T01:07:47.436EST | 1.7 | 5 km SW of Gladstone, New Jersey |
| 2024-04-05T20:51:18.307EST | 1.5 | 5 km WSW of Gladstone, New Jersey |
| 2024-04-05T20:39:11.635EST | 1.8 | 4 km W of Bedminster, New Jersey |
| 2024-04-05T19:39:23.815EST | 1.5 | 5 km NE of Whitehouse Station, New Jersey |
| 2024-04-05T19:10:49.196EST | 1.9 | 3 km SW of Bedminster, New Jersey |
| 2024-04-05T18:16:18.281EST | 1.9 | 5 km WSW of Bedminster, New Jersey |
| 2024-04-05T17:59:13.778EST | 3.8 | 7 km SW of Gladstone, New Jersey |
| 2024-04-05T16:21:07.157EST | 1.9 | 3 km ENE of Whitehouse Station, New Jersey |
| 2024-04-05T16:13:47.904EST | 2 | 6 km NNE of Whitehouse Station, New Jersey |
| 2024-04-05T14:40:20.185EST | 1.8 | 6 km ESE of Califon, New Jersey |
| 2024-04-05T13:32:13.627EST | 2.2 | 4 km NE of Whitehouse Station, New Jersey |
| 2024-04-05T13:21:55.646EST | 1.9 | 6 km E of Califon, New Jersey |
| 2024-04-05T13:18:48.029EST | 2 | 5 km SSW of Chester, New Jersey |
| 2024-04-05T13:14:13.044EST | 2 | 4 km S of Chester, New Jersey |
| 2024-04-05T12:49:49.389EST | 1.8 | 6 km NNE of Whitehouse Station, New Jersey |
| 2024-04-05T12:31:50.989EST | 1.8 | 7 km W of Bedminster, New Jersey |
| 2024-04-05T11:49:36.690EST | 2 | 5 km SSE of Long Valley, New Jersey |
| 2024-04-05T11:37:10.448EST | 1.8 | 6 km ESE of Califon, New Jersey |
| 2024-04-05T11:33:15.007EST | 1.9 | 4 km ESE of Califon, New Jersey |
| 2024-04-05T11:27:56.419EST | 1.9 | 6 km NNE of Whitehouse Station, New Jersey |
| 2024-04-05T11:20:20.203EST | 2 | 6 km NNE of Whitehouse Station, New Jersey |
| 2024-04-05T10:23:20.309EST | 4.8 | 2024 Whitehouse Station, New Jersey Earthquake |
What should I do if there’s an aftershock?
Should there be an aftershock, the Governor recommends you take immediate action to protect yourself and others.
- Drop to the floor, cover your neck, and hold on to something that is sturdy
- Stay indoors if possible and avoid doorways, windows, and exterior walls
- Listen for emergency alerts
- Assess your surroundings and see if theres damage