The recent magnitude-4.8 earthquake that struck beneath New Jersey was a rare event in a region where seismic risks are not fully understood. Scientists believe that the earthquake awakened an ancient fault in the Earth’s crust, which had not ruptured in over 200 years. Following the main quake, a 4.0-magnitude aftershock occurred, and at least 11 aftershocks have been reported in the area so far. Statistical models predict that there could be up to 27 aftershocks of magnitude 2 or greater in the coming week.
Researchers are working to identify the exact fault that caused the earthquake, suspecting it may have originated in the Ramapo fault zone in the Newark basin. However, due to the complex nature of the fault system, pinpointing the exact location of the rupture is challenging. The Northeast’s tectonic risk is rooted in ancient faults that have persisted from historic tectonic processes, presenting a different seismic hazard compared to the West Coast’s plate boundaries.
Despite the earthquake’s shallow depth and wide-reaching effects, the length of faults in the Northeast limits the magnitude of potential earthquakes. Scientists emphasize the need to better understand the region’s seismic risk and fault systems, particularly as funding for seismic monitoring networks has decreased. While monitoring aftershocks and understanding fault behavior is important, researchers believe that a global set of stations can effectively monitor larger earthquakes that are more relevant to society.
The earthquake served as a reminder to the East Coast about the importance of preparedness and building codes to minimize the impact of future seismic events. Frederik J. Simons, a geosciences professor, likened the earthquake to a wake-up call for the region, urging continued efforts in disaster preparedness and infrastructure resilience. While the event may have been unsettling, it also serves as an opportunity to improve understanding of the region’s seismic hazards and increase readiness for future earthquakes.
