PETROLIA, California – Residents of Northern California's Humboldt County were rocked by a magnitude-5.9 earthquake Thursday, but officials said there were no immediate reports of major injury or damage from the second large temblor to hit the area within a month.
The U.S. Geological Survey reported the quake struck at 12:20 p.m. about 35 miles northwest of the community of Petrolia and nearly 50 miles west of Eureka. The shaking was felt within a 150-mile radius, as far north as southern Oregon and as far south as Sonoma County, according to the USGS Web site.
Local officials and residents reported feeling a rolling sensation that caused items to fall from walls and shelves. Many said the movement didn't feel nearly as severe as the magnitude-6.5 quake that struck the same region Jan. 9 and caused more than $40 million in damage and one serious injury — an elderly woman who fell and broke her hip.
Eureka Fire Chief Eric Smith said crews were checking on structures that were damaged in the previous earthquake to make sure they're secure.
Phil Smith-Hanes, the county spokesman, said its Office of Emergency Services had not received any reports of major damage or injuries. "At first blush, it doesn't look like it's a big deal," he said.
Humboldt County Sheriff's Office spokeswoman Brenda Godsey, who was in a restaurant at the time, said the quake lasted 25 to 30 seconds, with none of the violent jolts felt last month.
"Everybody was very calm and just sort of waited it out," she said, adding that sheriff's dispatchers received no significant calls.
At the Petrolia General Store, a box of cereal and some sardine cans tumbled from the shelves, but the windows remained intact.
"Glass bottles were rattling, and you could see the lights swinging back and forth," said Amie Barr, 30, a store employee. "But it didn't feel as strong (as the Jan. 9 quake)."
She added, "We have them all the time, so we're pretty used to it here."
Steve Walter, a seismologist at the USGS in Menlo Park, said Thursday's quake was not an aftershock because it occurred on a different fault, but "we could speculate it might have been triggered by the one last month."
The temblor — initially reported by the USGS as magnitude-6.0 but later revised to magnitude-5.9 — did not trigger any tsunami warnings.
Walter said the far-northern coast of California is the most seismically active area in the state, but the potential for damage and injuries there is smaller because it's less populated.
"They get more earthquakes and much bigger quakes up there," he said. "They have had more in the past, and they will have more in the future than any other part of California."