On April 5, 2024, a magnitude 4.8 earthquake centered in Tewksbury, New Jersey, shocked many across the East Coast, particularly in New York City, where shaking was reported much stronger despite minimal damage near the epicenter. Researchers analyzed the earthquake’s rupture direction, concluding it funneled shaking northeastward, which explains the intensity reports. Over 180,000 people reported feeling the earthquake, marking the largest response ever recorded by the USGS. Ongoing research aims to clarify the mechanisms behind this unusual seismic event and assess future risks in the region.
A remarkable seismic event occurred on April 5, 2024, when a magnitude 4.8 earthquake struck Tewksbury, New Jersey, the largest recorded in the state since 1900. This disturbance not only surprised residents across the U.S. East Coast but raised intriguing questions regarding the varying intensities reported by individuals, particularly those situated as far as 40 miles away in New York City, compared to the relatively minimal damage observed near the epicenter. Researchers YoungHee Kim from Seoul National University and Won-Young Kim of Columbia University investigated this phenomenon in a study published in The Seismic Record. After visiting the area shortly after the earthquake, they anticipated visible property damage—such as fallen chimneys or cracked walls—but instead found a surprising lack of destruction. Reports from local law enforcement suggested a calm demeanor among residents near the epicenter, contrasting sharply with the numerous reports of strong shaking from individuals in New York City, which is about 65 kilometers northeast of the epicenter. The U.S. Geological Survey (USGS) received over 180,000 reports through its “Did You Feel It?” platform, marking the highest volume for a single earthquake to date. Approximately 42 million individuals experienced the earthquake across a wide geographic area, from Virginia to Maine, with reports indicating weak shaking southwest of the epicenter and light to moderate shaking to the northeast. Kim and her team concentrated on the earthquake’s rupture dynamics, utilizing Lg waves to analyze the direction of rupture. This analysis suggested that the quake’s rupture extended northeastward and downward along an east-dipping fault plane, which may have channeled the shaking away from the epicenter and directed it northeastward. In contrast to typical thrust faulting in the northeastern U.S., this earthquake displayed unique characteristics, indicating potential mechanisms of thrust and strike-slip movements along a previously hidden north-northeast trending fault. While some minor damages were registered, such as cracks and objects falling from shelves, further reconnaissance indicated some structural destruction, including part of the façade of Taylor’s Mill, a historic site in New Jersey. Current data do not pinpoint the exact fault responsible, but the locations of the shock waves suggest that the associated Ramapo fault system remained inactive during the incident. The investigation’s insights are expected to facilitate the identification of new seismic sources and enhance understanding of stress distribution and strain in the eastern United States. Seismologists like Oliver Boyd emphasized the importance of continued observation in the region, predicting valuable insights could emerge regarding crustal responses to seismic activity and potential risks associated with aftershock sequences. These ongoing studies will aid in understanding how localized earthquake effects vary according to magnitude and distance from the epicenter, ultimately improving strategies for mitigating seismic hazards.
The context of the Tewksbury earthquake of April 5, 2024, is essential for understanding its significance. Earthquakes in the eastern United States are often less documented due to historical records indicating infrequent but potent seismic activity. The Tewksbury event stands out as the most severe since 1900, causing confusion regarding its impact range and observable damage. The geographical distribution of felt reports across several states offers a unique opportunity to study the relationship between rupture mechanics and perceived intensity, especially in a region typically characterized by thrust faults. Understanding this earthquake contributes to broader insights into seismic hazards in areas not typically known for significant earthquakes.
In summary, the 2024 Tewksbury earthquake serves as an important case study for understanding the complexities of earthquake dynamics in the northeastern United States. The contrasting reports of shaking intensity and minimal local damage highlight the necessity for further research into the rupture mechanisms that govern such seismic events. Continued investigation by seismologists promises to enhance knowledge about fault systems and improve preparedness for potential future earthquakes.
Original Source: phys.org
