{"id":2119332,"date":"2026-08-28T15:35:30","date_gmt":"2026-08-28T12:35:30","guid":{"rendered":"https:\/\/analyse.optim.biz\/?p=2119332"},"modified":"2026-08-28T15:35:30","modified_gmt":"2026-08-28T12:35:30","slug":"remember-the-earthquake-that-hit-new-york-in-2024-scientists-finally-found-the-source","status":"publish","type":"post","link":"https:\/\/analyse.optim.biz\/?p=2119332","title":{"rendered":"Remember the Earthquake That Hit New York in 2024? Scientists Finally Found the Source"},"content":{"rendered":"

[analyse_image type=”featured” src=”https:\/\/gizmodo.com\/app\/uploads\/2026\/08\/2024-tewksbury-earthquake-1200×675.jpg”]<\/p>\n

\n
\n

On April 5, 2024, a magnitude 4.8 earthquake struck Tewksbury, New Jersey. The shaking took an estimated 42 million people from Virginia to Maine by surprise\u2014the East Coast certainly isn\u2019t known for its seismic activity. Now, researchers have finally figured out where this bizarre quake came from, and its origin wasn\u2019t what they expected.<\/p>\n

At first, the Ramapo Fault\u2014the largest in the region\u2014seemed like the obvious suspect, but the quake\u2019s epicenter was located too far away and its orientation did not align with the earthquake signal. In a study published earlier this month in the journal JGR Solid Earth, researchers took a closer look. Their findings suggest this quake originated on a previously unmapped, immature fault zone in the New Jersey Highlands, now named the \u201cMountainville Fault.\u201d<\/p>\n

\u201cWhat we are learning through these findings is that subtle, immature faults may pose a greater seismic hazard than the prominent, large faults that we traditionally focus on when assessing the earthquake hazards of a region,\u201d lead author Folarin Kolawole, a structural geologist at Columbia University\u2019s Lamont-Doherty Earth Observatory, told Gizmodo in an email.<\/p>\n

\u201cIn fact, we are finding that the faults that ruptured other major earthquakes in the East Coast also exhibit characteristics that are consistent with those of immature faults. So, our results may have implications that extend across the broader U.S. East Coast,\u201d he added.<\/p>\n

Fault forensics<\/h2>\n

Unlike the West Coast, which is where most earthquakes in the U.S. occur, the East Coast does not lie on a tectonic plate boundary. In this region, quakes occur within the North American plate, typically manifesting as thrust faulting along north-south trending faults.<\/p>\n

A fault is a fracture that separates two blocks of rock in a plate. When these blocks move against each other, the build-up and sudden release of stress can cause an earthquake.<\/p>\n

Previous research by scientists at Columbia University suggested the 2024 Tewksbury quake was unusual. The tremblor appeared to have occurred along a north-northeast trending fault and resulted from a combination of a thrust mechanism (when one block moves up and over the other) and a strike-slip mechanism (when the blocks move horizontally past each other). This hinted at the existence of a previously unknown fault plane.<\/p>\n

To investigate this hidden fault and why it slipped in April 2024, Kolawole and his colleagues relied on a combination of aftershock locations, field mapping, laboratory friction experiments, stress analyses, and LiDAR\u2014a remote sensing technique used to examine Earth\u2019s surface.<\/p>\n

\u201cWe were able to find the source of the earthquake by projecting the aftershocks of the 2024 event to the surface, and then went out to look at the rock exposures in the area the projection points to (in this case, Moutainville area of Tewksbury),\u201d Kolawole explained.<\/div>\n

Rethinking the East\u2019s seismic hazard<\/h2>\n

The researchers noticed that the upward projection of aftershocks indeed aligned with LiDAR imagery of an unmapped fault zone located about 2 miles (3.5 kilometers) west of the earthquake\u2019s epicenter.<\/p>\n

When they observed this lineament in the filled, they found that the exposed bedrock showed consistent fracturing patterns that matched the character of the signals seismometers recorded from the Tewksbury earthquake. But what was most surprising was that the geological characteristics of the fault zone suggested it was \u201cimmature,\u201d meaning it lacks the internal structure and prominent surface expression of larger, mature faults but is still capable of producing quakes.<\/p>\n

By tracing the Tewksbury earthquake back to what is now known as the Mountainville Fault, this study shows that the East\u2019s most significant quakes can occur outside of the region\u2019s large, well-mapped fault systems. While this particular event did not cause any major damage, it was the largest earthquake recorded in New Jersey since 1900, and its impact was felt by tens of millions across a wide swath of the nation.<\/p>\n

Thus, understanding the earthquake-generating potential of the region\u2019s lesser-known fault systems is critical to assessing risk, especially near densely populated areas like New York City. Now, Kolawole and his colleagues are working to determine the triggering mechanism of the Tewksbury quake to help inform earthquake forecasting in the region.<\/p>\n

Update: Friday, August 28, 2026<\/strong>: This story has been updated to include comments from Folarin Kolawole, lead author of the study. <\/em><\/p>\n<\/div>\n<\/article>\n

\n

On April 5, 2024, a magnitude 4.8 earthquake struck Tewksbury, New Jersey. The shaking took an estimated 42 million people from Virginia to Maine by surprise\u2014the East Coast certainly isn\u2019t known for its seismic activity. Now, researchers have finally figured out where this bizarre quake came from, and its origin wasn\u2019t what they expected.<\/p>\n

At first, the Ramapo Fault\u2014the largest in the region\u2014seemed like the obvious suspect, but the quake\u2019s epicenter was located too far away and its orientation did not align with the earthquake signal. In a study published earlier this month in the journal JGR Solid Earth, researchers took a closer look. Their findings suggest this quake originated on a previously unmapped, immature fault zone in the New Jersey Highlands, now named the \u201cMountainville Fault.\u201d<\/p>\n

\u201cWhat we are learning through these findings is that subtle, immature faults may pose a greater seismic hazard than the prominent, large faults that we traditionally focus on when assessing the earthquake hazards of a region,\u201d lead author Folarin Kolawole, a structural geologist at Columbia University\u2019s Lamont-Doherty Earth Observatory, told Gizmodo in an email.<\/p>\n

\u201cIn fact, we are finding that the faults that ruptured other major earthquakes in the East Coast also exhibit characteristics that are consistent with those of immature faults. So, our results may have implications that extend across the broader U.S. East Coast,\u201d he added.<\/p>\n

Fault forensics<\/h2>\n

Unlike the West Coast, which is where most earthquakes in the U.S. occur, the East Coast does not lie on a tectonic plate boundary. In this region, quakes occur within the North American plate, typically manifesting as thrust faulting along north-south trending faults.<\/p>\n

A fault is a fracture that separates two blocks of rock in a plate. When these blocks move against each other, the build-up and sudden release of stress can cause an earthquake.<\/p>\n

Previous research by scientists at Columbia University suggested the 2024 Tewksbury quake was unusual. The tremblor appeared to have occurred along a north-northeast trending fault and resulted from a combination of a thrust mechanism (when one block moves up and over the other) and a strike-slip mechanism (when the blocks move horizontally past each other). This hinted at the existence of a previously unknown fault plane.<\/p>\n

To investigate this hidden fault and why it slipped in April 2024, Kolawole and his colleagues relied on a combination of aftershock locations, field mapping, laboratory friction experiments, stress analyses, and LiDAR\u2014a remote sensing technique used to examine Earth\u2019s surface.<\/p>\n

\u201cWe were able to find the source of the earthquake by projecting the aftershocks of the 2024 event to the surface, and then went out to look at the rock exposures in the area the projection points to (in this case, Moutainville area of Tewksbury),\u201d Kolawole explained.<\/div>\n

Rethinking the East\u2019s seismic hazard<\/h2>\n

The researchers noticed that the upward projection of aftershocks indeed aligned with LiDAR imagery of an unmapped fault zone located about 2 miles (3.5 kilometers) west of the earthquake\u2019s epicenter.<\/p>\n

When they observed this lineament in the filled, they found that the exposed bedrock showed consistent fracturing patterns that matched the character of the signals seismometers recorded from the Tewksbury earthquake. But what was most surprising was that the geological characteristics of the fault zone suggested it was \u201cimmature,\u201d meaning it lacks the internal structure and prominent surface expression of larger, mature faults but is still capable of producing quakes.<\/p>\n

By tracing the Tewksbury earthquake back to what is now known as the Mountainville Fault, this study shows that the East\u2019s most significant quakes can occur outside of the region\u2019s large, well-mapped fault systems. While this particular event did not cause any major damage, it was the largest earthquake recorded in New Jersey since 1900, and its impact was felt by tens of millions across a wide swath of the nation.<\/p>\n

Thus, understanding the earthquake-generating potential of the region\u2019s lesser-known fault systems is critical to assessing risk, especially near densely populated areas like New York City. Now, Kolawole and his colleagues are working to determine the triggering mechanism of the Tewksbury quake to help inform earthquake forecasting in the region.<\/p>\n

Update: Friday, August 28, 2026<\/strong>: This story has been updated to include comments from Folarin Kolawole, lead author of the study. <\/em><\/p>\n<\/div>\n

[analyse_source url=”https:\/\/gizmodo.com\/freak-earthquake-that-hit-new-york-in-2024-came-from-a-hidden-fault-zone-2000804298″]<\/p>\n","protected":false},"excerpt":{"rendered":"

[analyse_image type=”featured” src=”https:\/\/gizmodo.com\/app\/uploads\/2026\/08\/2024-tewksbury-earthquake-1200×675.jpg”] On April 5, 2024, a magnitude 4.8 earthquake struck Tewksbury, New Jersey. The shaking took an estimated 42 million people from Virginia to Maine by surprise\u2014the East Coast certainly isn\u2019t known for its seismic activity. Now, researchers have finally figured out where this bizarre quake came from, and its origin wasn\u2019t what […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[226,53],"class_list":["post-2119332","post","type-post","status-publish","format-standard","hentry","category-politics","tag-crawlmanager","tag-gizmodo-com"],"_links":{"self":[{"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=\/wp\/v2\/posts\/2119332","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2119332"}],"version-history":[{"count":0,"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=\/wp\/v2\/posts\/2119332\/revisions"}],"wp:attachment":[{"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2119332"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2119332"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2119332"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}