Wow. What an afternoon. The quake rattled shoppers at Tysons Corner Center -- including me, your vacationing blogger -- with the trembling lasting about 7 to 10 seconds. Inside the Barnes and Noble on the first floor, the magazine racks shook and particles of dust from the ceiling streamed down. There was loud rumbling.

Up and down the East Coast, people poured out of shops and offices after the earthquake. (Charles Dharapak/AP)

Though cell phone lines were jammed, those who could get through reached friends and neighbors who reported their own bouts of shaking in other places in Northern Virginia. People quickly concluded that an earthquake had happened.

Needless to say, I hope everyone is okay. Be safe. And weigh in with your own experience below.