A recent study has provided new insights into the 4.8 magnitude earthquake that shook parts of New York City back in April, despite its epicenter being located in Tewksbury, New Jersey. Scientists from Columbia University have been investigating the cause of the quake and its implications for the region.

"The bedrocks here are colder, older, and stronger," said Dr. Folarin Kolawole, assistant professor of structural geology at Columbia University. Kolawole explained that because of the nature of the rock formations beneath New York, even smaller earthquakes can cause significant shaking.

"Here, even a small earthquake magnitude would create bigger shaking at the surface, in terms of the energy that is felt over a large area. It’s farther at farther distances."

According to the study by Columbia University’s Lamont-Doherty Earth Observatory, the earthquake did not occur along the well-known Ramapo Fault, which runs through parts of New York and New Jersey. Instead, it originated from an unmapped fault line. Fault lines are cracks in the Earth's crust where earthquakes typically happen. The fact that this quake occurred on an unknown fault has drawn attention from scientists.

"Through our field mapping, particularly mine and that of my students, we were able to find one of those subtle, poorly mapped faults in the area," Dr. Kolawole said.

Now, geologists are focusing on understanding these lesser-known faults. One such fault, located beneath 125th Street in Manhattan, has been producing small tremors. While not large enough to cause significant damage, these minor quakes serve as a reminder of the need for earthquake preparedness in the region.

"The big takeaway is that we need to be prepared. We need to better understand the nature of faults in areas where we already have minor seismicity happening, and use that as a template for assessing the seismic hazard of the region," Dr. Kolawole emphasized.

Some have questioned whether climate change could be contributing to the increase in seismic activity. However, Dr. Kolawole and his team say there is not enough evidence to link the April earthquake to climate change.

Researchers are calling for more funding to monitor fault lines more closely in order to better predict and prepare for future seismic events in the area.