DALLAS -- A small earthquake followed by an aftershock rattled a suburb west of Dallas overnight, cracking some walls and knocking down pictures, but authorities reported no serious damage and the unscathed Dallas-Fort Worth airport near the epicenter kept up normal flight operations.
Emergency officials said they had no indications of any injuries from Saturday's late-night quake.
The initial earthquake measuring a preliminary magnitude of 3.4 struck at 11:05 p.m. CDT on Saturday and was centered about 2 miles north of the Dallas suburb of Irving, the US Geological Survey's national earthquake monitoring center in Golden, Colo., reported. USGS Geophysicist Randy Baldwin told The Associated Press from Colorado that the initial quake lasted several seconds and appeared strong enough to be felt up to 15 or 20 miles away.
He said the smaller aftershock with an estimated 3.1 magnitude occurred four minutes later and just a few miles away in another area west of Dallas.
Irving's emergency operators were flooded with more than 400 calls after the initial quake as people reported such minor damage as cracks in some walls and a ceiling, pictures knocked down and a report of a possible gas leak, according to an emergency official, Pat McMacken. City officials said they were still following up on the various reports early Sunday.
The Dallas-Fort Worth International Airport continued routine operations even though the shaking was felt at the airport partly located in Irving's city limits, airport public affairs officer David Magana said. He told AP that the airport, which bustles at peak hours because of 1,800 daily departures and arrivals, was in a quiet period with very little air traffic late Saturday night.
He said the shaking caught the attention of those at the airport but didn't prompt any wider alarm.
"I wouldn't call it panic. I would call it surprise," Magana said by phone.
He said members of the airport operations team went out afterward and inspected landing strips, buildings and other airport installations and found no damage.
"There were no impacts or outages and no disruptions to flights," Magana said. "I felt it at my house. It shook it a little bit but it wasn't enough of a jolt to shake anything loose like you have in California. I've been in California and this was nothing like that."
Some reports in Dallas said the rattling was felt for many blocks all around Irving, beginning lightly and ending with a jolt. One person reported the quake was strong enough to knock open some file cabinets. Others reported that lightbulbs shattered during the quake.
Baldwin said more aftershocks are possible Sunday, noting the region has been periodically rattled by small quakes including a swarm of minor temblors in 2008. He also said magnitude estimates of the quake and aftershock could be revised after further study because the seismological station is rather distant at about 65 miles from the epicenters of the quake and aftershock.
About 1,200 reports by people who felt the quake were recorded with the Colorado earthquake monitoring center soon after it hit.