5.3 Aftershock Rattles Southland : Temblor: Frightened people flee stores and movie theaters and two fires are started. But there is little other damage from third-largest jolt since the Jan. 17 Northridge quake.

A powerful aftershock to the Northridge earthquake rolled across Southern California on Sunday, igniting two fires, disrupting power to thousands of San Fernando Valley residents and sending people fleeing from malls and movie theaters, but inflicting little physical damage.

The 5.3-magnitude quake, centered near Panorama City, was felt over a wide area of Los Angeles, Ventura and Orange counties when it hit at 1:20 p.m. It was the third strongest of more than 6,000 aftershocks that have struck the region since the Jan. 17 quake that killed at least 61 people and caused at least $13 billion in structural damage.

It was the seventh aftershock greater than magnitude 5.0, and it served to keep quake-jittery Angelenos on edge for yet another day.

Freeways sustained some “cosmetic cracking,” but no major damage, a state transit official said.

For fans camped outside the Dorothy Chandler Pavilion for tonight’s Oscar ceremonies, the shaker gave them a second authentic L. A. experience--but did not move them from their cherished places. Rhea Sprecher, an art teacher from Wisconsin, still managed to spot Debbie Allen, Goldie Hawn and others. “I felt some rumbling under my feet and I said: ‘Would that be an earthquake?’ ”

Inside, chandeliers swayed, seats rocked and huge pieces of scenery rattled. “Everybody, stay in your seats!” Oscar director Jeff Margolis ordered over the public address system.

Los Angeles city Fire Department officials said two fires were started by the earthquake. A mini-mall blaze in Van Nuys began because of electrical damage caused by the quake, and a transformer at a Department of Water and Power plant near Burbank Airport caught fire after earthquake damage caused oil in the unit to overheat.

Fire destroyed the Woodley Plaza shopping center in Van Nuys, burning a mini-market, video store and a restaurant, said Fire Department spokesman Jim Wells said.

But elsewhere, there was little damage.

In Malibu, a minor rockslide failed to disrupt traffic. And in Santa Monica, life in the bustling Third Street Promenade shopping and dining area was back to normal shortly after the temblor stopped.

“Seismically, this is a very expected behavior. Probably the big news story in this earthquake is people’s nerves,” said Caltech seismologist Kate Hutton.

In the San Fernando Valley and elsewhere, hundreds of people were evacuated from malls and theaters as a precaution.

About 1,000 people were removed from IKEA, a home furnishings store in Burbank. Despite shoppers’ anxiety, the evacuation was quick and orderly, said Dennis Rodriguez, the store’s operations manager.

“People were a little frightened. We got workers together with customers and guided them downstairs,” Rodriguez said. Some children were separated from parents but were reunited outside the building, he said.

Another 500 shoppers were evacuated from the Sherman Oaks Fashion Square mall, where the aftershock shattered plate glass alongside an escalator and sent some overhead spotlights crashing to the floor. No one was injured at the mall, where the first 34 of the complex’s 140 stores closed since the Jan. 17 quake reopened only Saturday, employees said.

“We had the rain yesterday, and another aftershock today,” said Bob Smith, a mall employee. “It’s been a tough weekend.”

The quake also rocked the Glendale Galleria shopping center.

“It shook us pretty hard,” said Drew Boghorsyan of the mall’s customer services department. “We heard the building just rumble. It was really scary.”

Boghorsyan said 26 of the 248 stores in the mall closed after the quake because merchants wanted to go home. He said he knew of no damage to the stores that closed.

A Sherman Oaks house, moved off its foundation by the Jan. 17 quake and scheduled for demolition today, was sent sliding another 20 feet down the hillside, imperiling other houses below.

At Valley movie theaters, moviegoers fled their seats as they were showered with broken plaster and other debris.

“There were some big tiles that fell down,” said John Corcoran, who was at the Fallbrook Mall theater in Canoga Park. The jolt also shook up construction workers still repairing damage from the January temblor.

James Booth of Burbank was on a bucket lift filling cracks on the second floor of the Cal State Northridge science building when the shaking hit.

“I thought it was this jackass shaking the bottom of the lift,” Booth said, pointing to a co-worker. Then, he added, “I thought the entire building was going to come down.”

At the Northridge Fashion Center, badly damaged in the January quake, 23 employees from a wrecking firm also were startled by the aftershock.

“We were in the center of the mall when it hit,” said Al Flores, a supervisor for Cleveland Wrecking Co. “It was a lot of bumping up and down. We just got all our people together, made sure everyone was all right, and got out of there.”

Engineer Chris Brock, of Law/Crandall Inc., a firm hired to evaluate the damage caused at CSUN by the Northridge quake, said inspectors have found “many new cracks, but nothing major yet.”

A Santa Monica conference of the Anxiety Disorders Assn. of America ended with a bang as the quake struck. “I tell you, the timing couldn’t have been better. It was the last day, the last minute, the last second and it hit. It was pretty ironic,” said association President Jerilyn Ross.

At Disneyland in Anaheim, some of the more elaborate attractions were temporarily closed down. At Universal Studios in Universal City, all attractions closed immediately after the quake.

Chris Cangco of Glendale was on a tram going over a bridge that falls apart as part of the special effects tour at Universal when the quake hit.

“I didn’t realize it was an earthquake at the time. I thought it was an effect of the . . . tram.”

But the shocks seemed too intense to be part of the attraction, he said, and the driver didn’t say anything. The ride continued, but the King Kong and earthquake attractions, scheduled to be included in the tour, were closed. Only when the 45-minute ride ended did someone inform the riders that a real earthquake had hit.

The aftershock also knocked out power to about 77,000 San Fernando Valley residents, most for five minutes or less, Department of Water and Power spokeswoman Mindy Berman said. However, about 7,000 customers in Van Nuys were without electricity for half an hour.

In Simi Valley, phone service in the western portion of the city was off for about 10 minutes.

Caltrans reported minor damage to freeways near the epicenter of the aftershock, but none serious enough to close any roads.

On the Golden State Freeway north of Granada Hills, the aftershock dislodged temporary asphalt filler that had been used to close a 6-to-8-inch gap caused by the Northridge quake. Temporary asphalt fixes also came loose in a concrete overpass at the interchange of the Simi Valley and San Diego freeways. Caltrans crews quickly refilled the gaps without shutting down any of the freeways.

“It’s not something that would alarm anyone,” said Caltrans spokeswoman Margie Tiritilli. “It’s super-minor.”

Caltech seismologists said the aftershock was expected and fell within the normal range.

“This is perfectly normal. This is what we expect,” said Egill Hauksson, a seismologist at Caltech. He said Sunday’s shaking occurred on the east side of the fault plane where the main shock occurred on Jan. 17, but was not on the same fault.

Seismic authorities said the aftershock was centered about two miles west-northwest of Panorama City, and about three miles northeast of the epicenter of the Northridge quake. It fell within a “pie-shaped aftershock zone” where shocks have been clustered, Hutton said.

The aftershock was closer to the surface than the Northridge quake, with preliminary estimates putting it about nine miles underground, compared to 12 miles for the Jan. 17 temblor.

With a preliminary magnitude of 5.3, the quake is 1/20 the magnitude of the Jan. 17 quake. Hutton said the average number of aftershocks continues to decline each month.

Sunday’s temblor “is an aftershock, but it is also an earthquake on its own” and will produce its own aftershocks, she said. However, there is only a 1 in 20 chance that it was a precursor of a larger quake, she said.

Only two other aftershocks, at magnitudes 5.6 and 5.9, have been stronger than Sunday’s, and both occurred the day of the Northridge quake.

Sunday’s aftershock was followed by two lesser ones, a 3.4-magnitude aftershock recorded at 3:34 p.m., and another reading 2.7 at 8:05 p.m., seismologists said.

Meanwhile, a spokesman for Farmers Insurance Co. said Sunday’s aftershock could trigger a temporary suspension of underwriting earthquake insurance in the region.

“Geologists may call this an aftershock, but this is a separate quake for insurance purposes,” said Jeffrey Beyer, spokesman for Farmers.

State law allows insurers to impose a moratorium of up to 60 days on sales of earthquake insurance when an quake occurs. A moratorium imposed after the Jan. 17 Northridge quake covered about 100 square miles and lasted no more than 30 days at many companies.

“I don’t know of any moratoriums still in effect,” Bill Schulz, spokesman for the California Department of Insurance, said.

The aftershock prompted Valley business owners and authorities to close some public structures so they could check for structural damage.

In Burbank, owners shut down the 75-store Media City Center mall for the day after sprinklers jolted by the aftershock drenched some shoppers. City building inspectors also ordered the mall parking structure closed until it could be inspected, said Lt. Don Brown, of the Burbank Police Department.

A spokesman for the Los Angeles Unified School District said schools will be open “as usual” today, although workers will inspect repairs from the January quake to make sure they held. In all, 76 public schools were damaged in January.

Doug Brown, the district’s facilities director, said, “We will be out at the schools where there was previous damage to make sure the repairs are still holding.”

“We’re going to hit the ones that had the most damage and the least permanent repair work done and work our way back from there.”

The Washington, D.C.-based Anxiety Disorders Assn. had been discussing such problems as traumatic stress disorders, like those brought on by the Jan. 17 quake, in its four-day conference at the Loews Santa Monica Beach Hotel.

As the final seminar drew to a close, the fifth-floor banquet room began to shake and the chandeliers rattled noisily. The seminar ended with applause and laughter--for the quake.

On Friday, the 550-person conference had featured a seminar called “The Los Angeles Earthquake and Post-Traumatic Stress Disorder.” And as their time in the city came to a close, some of the psychiatrists and social workers joked about earthquakes.

“Jokingly, we who’d never experienced an earthquake said, ‘Gee, I wish I could feel just a little one so I could know what it feels like,’ ” Ross said.

* FEW REPEATS: Sunday’s temblor caused few problems at Valley sites hit hard by the Jan. 17 quake. B10