Sonic Boom, Not Earthquake, Caused The Tremors That Rocked South Jersey

On Thursday, residents in New Jersey and Long Island reported "mysterious" shakings in the ground. The incident's initial report said the tremors were caused by a sonic boom, not an earthquake.

According to the U.S. Navy, two of their aircraft could have caused the sonic booms that rocked southern New Jersey. The U.S. Geological Survey (USGS) documented a sonic boom about 3 kilometers in Hammonton, New Jersey's north-northeast part. The team didn't find any seismic activity which ruled out earthquake as a likely cause.

An F-18 and an F-35C military aircraft were undergoing supersonic tests near the New Jersey coast. The test wing is not just crucial to the safe test, but also to the assessment of all Navy and Marine Corps aircraft types that are both in service and in progress, added the Navy.

"Navy spokeswoman Connie Hempel said supersonic tests flights are done almost daily in the same area but that most sonic booms aren't felt on land," said a report.

A USGS geophysicists recorded a total of nine booms that occurred in the span of 90 minutes. A sonic boom is a loud blast due to a shock wave coming from an aircraft traveling beyond the speed of sound.

The tremors were first felt and reported near Cape May County in southern New Jersey. Before 2 p.m., the tremors moved up to the coastline. Within the hour, people in Staten Island, Amityville, Long Island and southeastern Connecticut reported similar incidents.

The police departments in New Jersey's Toms River, Hamilton Township and Ocean Country received so many distress calls about the tremors that they had sent out advisories asking the public to stop calling the emergency line 911 unless there is a real emergency.

Photo: Steve Jurvetson | Flickr