3.8 Magnitude Quake Shakes New England, Ignites Interest and Curiosity About Seismic Risks

On Monday, a 3.8 magnitude earthquake struck off the coast of York Harbor, Maine, surprising residents across southern Maine, Seacoast New Hampshire, and much of New England. The quake, which occurred at 13.2 kilometers below the surface of the Atlantic Ocean, prompted a flurry of calls to public safety dispatch centers, although remarkably, officials reported no injuries or property damage in the aftermath. This earthquake has reignited interest and concern about seismic activity in the region, leading many to wonder about its rarity and the potential for aftershocks. According to the U.S. Geological Survey (USGS), there have been over 50 recorded earthquakes in Maine and New Hampshire since the year 2000, but incidents of this magnitude are not frequent. The quake is now ranked as the third-highest in the region this century, following a stronger 4.7 magnitude quake near Hollis, Maine, in 2012. Experts from the University of New Hampshire, Sophie Coulson and Majid Ghayoomi, weighed in on the nature of this seismic event. They noted that while smaller earthquakes happen periodically, the occurrence of a quake felt by such a significant number of people is indeed rare for the region. "Generally in New England, we see these somewhat larger earthquakes every five-ish years or so," Coulson explained, emphasizing that the sensation of shaking felt by locals was an unusual experience. The geological context of this event can be traced back hundreds of millions of years to the formation of the Appalachian Mountains, when two continents collided. This ancient tectonic activity left behind faults—"pre-existing planes of weakness"—that can lead to earthquakes. Coulson suggested that the recent quake was driven by pressure changes in the Atlantic Ocean, which are being pushed towards land as tectonic plates shift. Despite the excitement and concern surrounding the quake, experts believe the likelihood of aftershocks is low. "We would typically expect aftershocks to be smaller than the 'mainshock' event, so if there are aftershocks from this event over the next hours or days, they may be small enough that we don't actually feel them," said Coulson. The USGS has estimated a 13% chance of at least one aftershock of magnitude 3.0 or greater in the upcoming week. The loud noise reported by many residents during the earthquake also offers insights into its characteristics. Ghayoomi noted that such a sound indicates a shallow depth of the quake, suggesting a significant release of built-up pressure. Many residents likened the experience to an explosion or a heavy vehicle colliding with a structure, highlighting the dramatic nature of the incident. Even with the potential for minor aftershocks, Ghayoomi pointed out that small earthquakes can serve a practical purpose. "Small earthquakes are often not bad because they increase people's awareness," he noted. They not only prepare communities but also help in releasing accumulated energy in the Earth’s crust. On Star Island, one of the Isles of Shoals, locals reported no apparent changes post-earthquake. Winter caretaker Alexandra de Steiguer described her initial confusion over the quake, believing an airplane might have struck the house due to the loud roar and shaking she experienced. As the region processes this surprising event, many remain curious about the state of seismic activity in New England. While the likelihood of another substantial earthquake remains uncertain, experts emphasize that the geological makeup of the region is capable of producing occasional shakes, keeping residents on alert but also educated about the nature of these phenomena.