What causes earthquakes in the Northeast, like the magnitude 4.8 that shook New Jersey? A geoscientist explains

It's rare to feel earthquakes in the U.S. Northeast, so the magnitude 4.8 earthquake in New Jersey that shook buildings in New York City and was felt from Maryland to Boston on April 5, 2024, drew a lot of questions. It was one of the strongest earthquakes on record in New Jersey, though there were few reports of damage. A smaller, magnitude 3.8 earthquake and several other smaller aftershocks rattled the region a few hours later. We asked geoscientist Gary Solar to explain what causes earthquakes in this region.