BE READY FOR 'BIG ONE,' EXPERTS URGE AT CALTECH.

Byline: Kerry Cavanaugh Staff Writer

PASADENA - On Saturday's 10th anniversary of the Northridge Earthquake, hundreds of San Fernando Valley and Los Angeles area residents crammed a Caltech auditorium to hear that the ``big one'' is coming - but nobody knows when. So be prepared.

Seismic expert Lucy Jones put it straight to the audience, saying: ``There's a good chance it will happen in 200 years, and definitely in 10,000 years.''

That was little consolation to people like Brad Perkins, 25, of Van Nuys, who like most of the audience felt the terrible rumbling and shaking from the magnitude 6.7 quake on Jan. 17, 1994, and survived the costliest natural disaster in U.S. history, a catastrophe that killed 57 people, injured nearly 12,000 and caused more than $40 billion in damage.

Perkins' family had to move out of their Sherman Oaks town house after the quake knocked the building off its foundation and left cracks laced through the walls.

``If I can survive that, I can survive another one - but I don't want another one,'' Perkins said.

Scientists at the earthquake anniversary event sponsored by Caltech and the U.S. Geological Survey discussed the near-constant seismic activity and web of fault lines across Southern California and how conditions attract the attention of seismologists from across the nation.

Southern California has about nine magnitude 2.0 quakes a day and there's a magnitude 3.0 earthquake - which some people will feel - at least once a day on average.

But it's the ``big one'' that stirred curiosity and fear.

The scientists dismissed a recent prediction that a magnitude 6.4 or greater quake will hit the San Andreas Fault by Sept. 5, saying their knowledge has not reached the point where they can predict quakes with any accuracy.

Rather than trying to predict quakes, the experts urged preparedness.

Shaking demonstrations showed how straps could hold computer monitors and water heaters in place. Vendors displayed waxes, putties and gels to keep breakables on the shelf. And safety officials urged people to pack emergency first-aid kits with water, flashlights and food.

John Hall, a civil engineer at California Institute of Technology in Pasadena, painted a grim picture of house and office building retrofitting efforts since the Northridge Earthquake.

Two-thirds of pre-1933 brick buildings are retrofitted, but those still may not survive a strong quake, authorities said.

``It just seems to me that society is willing to take the chance with these buildings,'' Hall told the crowd.

Even the typical wood-frame and stucco-skin houses, which were once considered light and ductile enough to weather a major quake, may not be able to handle hard shaking.

``The whole concept of how we build our houses really needs some new thinking,'' said Hall.

Making Southern California earthquake-proof won't be easy and it won't be cheap, experts said Saturday.

But on a beautiful sunny winter day like Saturday, that didn't bother Gil Stearn, a retired petroleum geologist in Anaheim.

``You pay a premium to live in Southern California.''

For more information about earthquakes, log on to the USGS Web site at http://pasadena.wr.usgs.gov and look at real-time maps of earthquakes that give the location and magnitude minutes after a quake. Another Web site, www.scign.org, provides information on the array of GPS stations in Southern California.

Kerry Cavanaugh, [phone]

kerry.cavanaugh(at)dailynews.com

CAPTION(S):

2 photos

Photo:

(1 -- color) Lucy Jones of the U.S. Geological Survey stresses that there is still much to be learned about earthquakes. See story Page 20.

Tom Mendoza/Staff Photographer

(2) Judah Walburn, 10, gives an example of retrofitting on wooden models Saturday at an event to give temblor information and solutions on the 10th anniversary of the Northridge Earthquake.

David Sprague/Staff Photographer