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2024-04-05, M4.8, New Jersey

On April 5, 2024 at 14:23:20 UTC (10:23am local time) a M4.8 earthquake occurred near Whitehouse Station, New Jersey, USA, around 60km ESE of New York City. It has been followed by an aftershock sequence of 41 further events of smaller magnitude so far.

This earthquake was caused by a combination of shallow oblique reverse and strike-slip faulting, occurring at a depth of only around 5km. It is an example of an “intraplate” earthquake that occur on existing faults, away from a tectonic plate boundary.

The event was recorded by seismic stations in Ireland operated by DIAS in the Irish National Seismic Network (INSN), see figure below, with the signal just visible above the background noise. An earthquake of magnitude M4.8 at a distance of around 5000km is close to the limit of what can be detected, as the amplitude of the ground motion from the seismic waves reduces with distance as the energy spreads out and is attenuated.

Earthquakes in this part of the US are uncommon but do happen occasionally. 13 earthquakes of M4.5 and larger have been recorded within 500km of this event since 1950, with the largest being the damaging and widely felt M5.8 Mineral Virginia earthquake on 23 August 2011.

While this earthquake was relatively small in global terms, earthquakes of this magnitude are commonly felt more widely in the eastern US (compared to the Western USA) because of the relatively high population density and efficient wave propagation through older cratonic crust. Shaking from this earthquake was felt by millions of people across the Northeast US (see intensity map from the USGS below), but no significant damage to buildings or injuries to people have been reported.

Felt intensity map of the 5 April 2024 M4.8 New Jersey earthquake, showing the effects of ground shaking that occurred during this event, source: USGS

More information is available at the below resources:



Past Seismograms
follow this link

Live Seismograms
All stations here
Filtered versions here
DSB - Dublin
VAL - Kerry

Past Spectrograms
follow this link
Live Spectrograms
All stations here
ITIP - N. Tipperary
IMAY - Mayo