Geologists Folarin Kolawole and Zachary Foster-Baril from Lamont-Doherty Earth Observatory are on a mission to analyze a rock outcrop near Lake Solitude Dam in High Bridge, N.J., close to the epicenter of a recent earthquake. After a magnitude 4.8 earthquake struck the New York metropolitan area on April 5, 2024, the team quickly mobilized to study the event. The quake originated 4.7 kilometers under Whitehouse Station, sparking curiosity about the possibility of larger earthquakes in the region.
The area’s ancient granitoid gneiss outcrops are marked with old earthquake cracks, hinting at a complex seismic history. The Ramapo Fault, believed to be mostly inactive, runs through Pennsylvania, New Jersey, and New York, branching into numerous secondary faults like the one responsible for the recent quake. Geologists aim to uncover the mechanics behind earthquakes by studying rock fractures and other features linked to past events.
During fieldwork near the epicenter, Kolawole’s team discovered old earthquake fractures and witnessed a magnitude 3.8 aftershock, reinforcing the need for further study. Weeks later, they continued their search for earthquake clues in various locations, including a waterfall-covered outcrop and a wooded knoll with uncharted gneiss formations. The team’s discoveries, including ancient fault remnants and slickensides, shed light on the seismic history of the region. Despite the challenging conditions, the geologists are determined to unveil more secrets hidden in New Jersey’s ancient rocks.
