Earthquakes large enough to be felt by a lot of people are relatively uncommon on the East Coast. Since 1950 there have been about 20 quakes with a magnitude above 4.5, according to the United States Geological Survey. That’s compared with over 1,000 on the West Coast. East Coast residents were jolted Friday by a 4.8-magnitude earthquake centered near Lebanon, New Jersey with weak rumblings felt as far away as Baltimore and the Massachusetts-New Hampshire border. No life-threatening injuries or major damage have been reported.