New York City's skyscrapers are built to withstand most earthquakes
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... The ground rumbled Friday beneath New York City, home to famous skyscrapers like the Empire State Building and One World Trade Center. Though buildings that can reach above 100 stories might seem especially vulnerable to earthquakes, engineering experts say skyscrapers are built with enough flexibility to withstand moderate shaking.

The 4.8 magnitude quake on Friday morning was centered about 45 miles (72 kilometers) west of the city in New Jersey. Aftershocks continued, with a 2.5 magnitude quake on Saturday morning. But no major damage had been reported to the city's mass transit system or its 1.1 million buildings.

Operators of the iconic 103-floor Empire State Building posted "I AM FINE" on Friday on the building's X account.

New York's skyscrapers have been generally built to withstand winds and other impacts far greater than the earthquakes generally seen on the East Coast, said Elisabeth Malsch, a managing principal at Thornton Tomasetti, a New York engineering firm that's done major work on the Empire State Building, Chrysler Building and the Brooklyn Bridge, among other major city landmarks.

"The earthquake that we design for is one that's unlikely to happen. It's a thousand-year event," she explained. "So we don't expect it to happen more than once in a thousand years."

Skyscrapers, by design, are less susceptible to the ground-shaking action of earthquakes than shorter structures because they're made to sway ever so slowly and slightly to protect themselves against powerful, hurricane force winds, Malch said. ...