Here's What Caused Earthquake That Shook Houses Across LI: USGS

LONG ISLAND, NY — With thousands turning to social media to compare notes on what Gov. Kathy Hochul has called "one of the largest earthquakes on the East Coast in the last century," experts are now explaining what caused the event.

According to the United States Geological Survey, or USGS, the 4.8 magnitude earthquake Friday, near Whitehouse Station, NJ, "occurred as a result of oblique reverse and strike-slip faulting at shallow depths in the crust. Although this event did not occur near a plate boundary, such 'intraplate' earthquakes can and do occur. While this earthquake is relatively small globally, earthquakes of this magnitude are commonly widely felt in the eastern United States because of efficient seismic wave propagation in the region."

Earthquakes in the eastern US are infrequent — but not unexpected, the USGS said, adding that since 1950, 40 other earthquakes of magnitude 3 and larger have occurred within 250 km of Friday's earthquake.

"In that time range, the April 5, 2024, earthquake is the largest. Within 500 km of the April 5 earthquake, 13 earthquakes, M 4.5 and larger have been recorded since 1950, the largest being the August 23, 2011, M 5.8 Mineral, VA, earthquake which caused substantial damage and was felt throughout the eastern United States."

Friday's earthquake occurred in a region where faults have been previously identified and may be reactivated at any time, the USGS said.

Residents have expressed shock, echoing the statement, "The house shook" after the quake — and New York sent out alerts warning about after shocks.