Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: TUESDAY, January 18, 1994                   TAG: 9401180194
SECTION: NATIONAL/INTERNATIONAL                    PAGE: A10   EDITION: METRO 
SOURCE: MICHAEL FLEEMAN ASSOCIATED PRESS
DATELINE: PASADENA, CALIF.                                LENGTH: Medium

THIS QUAKE STILL WASN'T THE BIG ONE

The quake, which measured 6.6 on the Richter scale, proved that Southern California can suffer significant damage without the dreaded 8.0 or stronger earthquake that scientists say could hit the region within 30 years.

Freeways and buildings crumbled after Monday's quake, gas mains caught fire and utility service was disrupted as far away as Canada.

But the quake was believed to have done nothing to ease pressure on the dreaded San Andreas Fault. That's where the Big One would occur, possibly causing cataclysmic damage and widespread death and injury.

The only consolation for nervous Southern Californians was that Monday's quake didn't put any pressure on the San Andreas, 20 miles away from the epicenter in the Los Angeles suburb of Northridge.

"It could not be a trigger" for a San Andreas quake, said Lucy Jones, a seismologist at the California Institute of Technology in Pasadena.

Scientists said the quake was caused by the constant movement of Southern California toward San Francisco, which places enormous stress on the Los Angeles Basin.

The Richter scale is a measure of ground motion as recorded on seismographs. Every increase of one number means a tenfold increase in magnitude. Thus a reading of 7.5 reflects an earthquake 10 times stronger than one of 6.5.

Scientists said Monday's quake may have occurred along part of the same fault system that caused the Whittier Narrows earthquake.

But unlike the much stronger Landers quake, Monday's quake was located much closer to a heavily populated area. Landers is about 90 miles east of downtown Los Angeles; Monday's was centered in Northridge, 20 miles to the northwest of L.A.

Scientists said Monday's quake showed that timing and location can be just as important as magnitude - and that Southern California doesn't need a Big One to suffer heavy losses.

Seismologists said there was a 50-50 chance of a magnitude 5 aftershock in the next week and a one-in-four chance of a magnitude 5.5. The odds of a magnitude 6 aftershock in the next week are 1-in-10.

Monday's quake, like others before it, helped push two mountain ranges higher and shrink the San Fernando Valley.