5.0 QUAKE RATTLES AREA, INJURES NONE : SMALLER AFTERSHOCKS FOLLOW TEMBLOR.

Byline: Alicia Doyle and Terri Hardy Daily News Staff Writers

At least eight aftershocks from the 1994 Northridge Earthquake struck Saturday morning, waking slumbering residents from Ventura County to Los Angeles but causing no injuries or major damage, authorities said.

At 3:37 a.m., a 5.0-magnitude aftershock hit seven miles north-northeast of Simi Valley, followed by a succession of smaller jolts, said Steve Bryant, a seismologist at the California Institute of Technology in Pasadena.

The large aftershock didn't surprise scientists, who said it's all part of living in temblor-prone California.

``We have big earthquakes in Los Angeles, and we have big aftershocks,'' Bryant said. ``While the rate of aftershocks decline with time, the size doesn't go down.''

Saturday's 5.0 aftershock was the 10th of that magnitude or greater since the Northridge Earthquake, Bryant said. The last aftershock of 5.0 or more was June 26, 1995.

In all, there have been thousands of aftershocks since the Northridge Quake, some of them noticeable - and more are expected.

Seismologists were unable to determine Saturday exactly how far from the epicenter this latest temblor was felt. Caltech received no calls from outside the greater Los Angeles area, Bryant said.

For some residents, the scientific detachment of the seismologists did little to calm their quake-jangled nerves.

Capt. Bill Apodaca, of the Los Angeles County Fire Department, and his wife were asleep in their Simi Valley home when a low, unmistakable rumble awakened them.

``It was violent enough to get you out of bed,'' Apodaca said. ``It definitely scared me - got our attention.''

He and his wife had not calmed down from the initial jolt when the second part of the one-two punch shook their house. ``We thought it was over. We said, `Boy, that was something,' and all of a sudden `Oh, God, here we go again.' ''

Following Saturday's first 5.0 aftershock, a 4.0-magnitude tremor hit three minutes later at the same location. Then, three 3.2-magnitude aftershocks hit seven miles west of Newhall between 3:54 a.m. and 4:33 a.m.

At 4:55 a.m., a 3.8-magnitude struck eight miles north-northeast of Simi Valley. Nearly three hours later, a 3.0-magnitude hit seven miles west of Newhall, followed an hour later at 9:13 a.m. with a 3.4-magnitude temblor at the site of the first quake.

The quake knocked down merchandise from some store shelves and loosened ceiling tiles at a Kmart store in the Santa Clarita area.

For some, the temblor managed to rattle more than just walls and ceilings.

Al Reynolds of Calabasas had lived in the Northridge Meadows apartment complex in 1994 when the quake collapsed the building, killing 16 residents. His apartment was on the first floor, but he was at work that morning when the temblor struck at 4:31 a.m.

``I would have been dead,'' Reynolds said.

After Saturday's jolt, Reynolds said he was ``just glad to be alive.''

The early morning shaker also renewed residents' resolve to prepare for quakes.

The Northridge Quake of 6.7-magnitude struck at 4:31 a.m. Jan. 17, 1994, leaving 72 dead and caused $25 billion damage, according to recently updated figures.

Coincidentally, the American Red Cross' San Fernando Valley district held an earthquake preparedness fair Saturday in Van Nuys, drawing about 1,000 people, largely because of the shaking.

``It was the most fluky timing you could imagine,'' said Kent Wallace-Meggs, a Red Cross spokesman. ``There was quite a bit of interest because of the aftershock. It's time to get your stuff together or to rotate your supplies.''

Bill Hartenstein, an amateur seismologist who lives in Burbank, actually welcomed the big aftershock. Hartenstein said he was only too glad to get out of bed and follow the aftershocks as they were recorded on his computer.

``I sat up all night. I really enjoyed watching the seismograph,'' he said.

By Saturday afternoon, Hartenstein said he had recorded at least 34 aftershocks. ``It's great to see the points on the computer and know that the ground is raising.''

EARTHQUAKE PREPAREDNESS

Following are some of the suggestions from the Los Angeles County Sheriff's Department and the American Red Cross for preparing to survive a major earthquake:

Develop a family plan.

Decide where your family can reunite if separated.

Be familiar with the safe spots in each room, so you can seek protection under sturdy tables and desks or against inside walls. Note danger spots to avoid such as windows, mirrors, hanging objects and tall, unsecured furniture.

Know where the gas, water and electricity turnoff sites are located and how to shut them off.

Secure water heaters and appliances.

Maintain emergency food and water (a three-day supply).

Create a survival kit and include a flashlight, portable battery-operated radio, extra batteries, prescription medicine, first-aid supplies, clothing and sanitation needs.

A small kit should also be placed in each vehicle.

Keep first aid and cardiopulmonary resuscitation knowledge up to date.

After an earthquake

Check yourself and those around you for injuries.

Don't move seriously injured persons unless they are in immediate danger.

Check for utility leaks and broken electrical or sewage lines.

Survey the house for cracks and signs of damage.

Check water and food supplies.

Remember emergency water can be found in water heaters, melted ice cubes, the toilet tank and canned vegetables.

Use a portable radio for instructions and news reports.

Do not drive your car unless necessary - roads need to be clear for emergency vehicles.

CAPTION(S):

Photo, Map, Box

Photo: A Kmart worker in Santa Clarita repairs some ceiling tiles shaken loose by Saturday's 5.0-magnitude earthquake.

Gene Blevins/Special to the Daily News

Map: (color) Aftershock epicenter

Box: EARTHQUAKE PREPAREDNESS (see text)