Peak ground velocity from a magnitude 4.8 earthquake under Tewksbury township, N.J., (gold star) on April 5, 2024. The shaking was relatively weak at the epicenter but spread unexpectedly far, mainly to the northeast. (Courtesy Won-Young Kim)
On April 5, 2024, a magnitude 4.8 earthquake hit Tewksbury township in northern New Jersey, causing widespread alarm. This was the largest quake since 1884, when a magnitude 5 quake shook the seabed off Brooklyn, causing significant damage. While existing models predicted substantial damage at the epicenter, the reality was quite different. Surprisingly, New York City experienced stronger shaking than expected, leading to minor damage. The effects of the quake reached as far as Virginia and Maine, challenging previous assumptions about earthquake hazard in the region.
The earthquake, while not significant on a global scale, was felt by an estimated 42 million people in the densely populated U.S. Northeast. The U.S. Geological Survey received a record number of reports through an online portal, indicating the widespread impact of the event. Contrary to expectations, the quake did not cause significant damage at its epicenter, with only minor incidents reported. However, the shaking extended far beyond the epicenter, causing unexpected effects in nearby cities and even reaching as far as New England.
A study conducted by researchers, including Won-Young Kim of the Lamont-Doherty Earth Observatory, analyzed the seismic waves generated by the earthquake. The findings suggested that the quake occurred on a previously unmapped fault, explaining the unusual pattern of shaking observed. The energy released by the quake traveled along the fault line, bouncing back and forth between the surface and the Earth’s mantle, resulting in amplified shaking in distant locations.
The aftermath of the April 5 earthquake has spurred new research efforts, aimed at understanding the dynamics of seismic activity in the region. By monitoring aftershocks and studying the geological implications of the event, scientists hope to improve earthquake forecasting and preparedness in the future. The findings from this event have challenged existing notions of earthquake hazard in the U.S. Northeast, highlighting the need for continued research and monitoring to mitigate future risks.
