Originally posted at 7:07 a.m. March 17, 2014.
UPDATE at 10:54 a.m.: St. Patrick's Day got off to a shaky start today when a magnitude-4.4 earthquake centered southeast of Encino in the Santa Monica Mountains gave residents a jolt and several seconds of shaking, but there were no reports of any damage or injuries.
The quake, which was originally estimated by the U.S. Geological Survey at magnitude-4.7 but was later downgraded, was centered about six miles north- northwest of Westwood and about five miles underground. The jolt was felt as far away as Santa Barbara and into Orange County.
"We've had a couple of aftershocks greater than magnitude 1.5," USGS seismologist Robert Graves told reporters about an hour after the quake was reported. "The most recent was at 7:23 (a.m.). We had a magnitude 2.7, which would cause very minor shaking, probably felt in the epicentral region.
"We're continuing to analyze the data, but at this point, this seems to be what I would call a rather typical earthquake of moderate magnitude," Graves said. "We don't expect there will be much damage."
Graves said the quake was a "reminder that we live in earthquake country" and emphasized the importance of residents devising an earthquake plan that includes emergency sources of food and water.
Mayor Eric Garcetti echoed that sentiment, calling the "Shamrock Shake" temblor a reminder "that every L.A. family must be prepared with food, water and other essentials, as well as a plan."
The Los Angeles police and fire departments went into their standard earthquake mode after the shaker to survey neighborhoods and critical infrastructure in search of any potential damage, but none was found.
Metro rail lines were delayed briefly as crews inspected tracks for possible damage from the earthquake. Service returned to normal a short time later when no damage was detected.
Los Angeles International Airport operations were not affected by the quake, according to airport police. Los Angeles Unified School District schools were also unaffected.
The California Highway Patrol reported no damage to Los Angeles-area roadways from the earthquake.
Officials at UCLA said the campus in Westwood, despite its proximity to the epicenter, did not suffer any damage.
According to Orange County Fire Authority Capt. Steve Concialdi, the quake was felt in parts of Orange County, but he said there have been no reports of damage or injuries.
Egil Hauksson, a USGS seismologist at Caltech, said the quake was rare in that is was centered in the midst of the Santa Monica Mountains, which are essentially solid rock. He said quakes are generally centered either north or south of the range, but not within the range.
Caltech officials also noted that the experimental early warning system for quakes worked, giving seismologists about a two-second warning before the shaking began.
--City News Service
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