Earthquake rattles heart of Downtown San Francisco

SAN FRANCISCO – A magnitude 3.7 earthquake struck just off the coast of San Francisco Friday morning, adding a jolt to millions of residents to their morning routine.The tremor occurred just after 7 a.m. local time, according to the U.S. Geological Survey. It was felt throughout the Bay Area, as far south as San Jose, according to the USGS shake map.The epicenter was located about 3 miles northwest of the San Francisco Zoo, placing it just off the coast in the Pacific waters. The USGS says the quake had a depth of about 5 miles.A 3.7 quake is relatively minor and quakes of that strength are common in Northern California. There were no initial reports of any damage, but the San Francisco Muni transit system reported temporary delays on its subway system so tunnels could be checked for any issues. Regular service was to resume once checks were completed.