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Earthquake Monitoring to Be Expanded to All Parts of State


California's network of seismic monitoring stations will spread from Southern California to cover the entire state and total 1,200 stations under a new state appropriation announced Tuesday by the Davis administration.

The $2.9-million program includes $1.84 million for Caltech to operate its Southern California network of 600 stations, completed in the last year, and will add 600 stations in the north. When complete, it will enable state scientific and emergency authorities to pinpoint the precise location and damage pattern of any sizable quake within minutes of its occurrence no matter where it occurs in California. Some quakes in rural regions have been beyond quick identification.

The program, announced in a Sacramento news conference by the director of the state Office of Emergency Services, Dallas Jones, supplants the traditional federal funding of such stations.

The federal government had announced last year that it would cut much of its funding, although the Federal Emergency Management Agency will continue to contribute $1 million a year, and the U.S. Geological Survey is expected to make a smaller contribution.

Gov. Gray Davis said that a new umbrella group, the California Integrated Seismic Network, has been created to coordinate quake monitoring in the state. It provides information at

"It's a more robust monitoring system," bringing together the efforts of the Geological Survey, Caltech, UC Berkeley and the California Geological Survey, Jones said.

A vital feature of the Southern California network has been so-called shake maps, which depict the shaking in sizable quakes not only near the epicenter but in all areas where the quake is felt.

Such shake maps have been available mainly in Southern California. With the new state funding, they will now be available throughout the state, and in a major temblor could be assembled by any of the contributing monitoring agencies if one or more were disabled regionally, according to Caltech seismologist Egill Hauksson.

Last year, Hauksson expressed concern that with the reduction of federal funding, the Southern California system might be diminished in scope. He launched a successful effort to convince the Davis administration that the state should take over responsibility for continuing and expanding the system.

In both of California's most damaging quakes of recent years--the 1989 Loma Prieta temblor in the Bay Area and the 1994 Northridge quake--authorities were unsure for up to two days just where all the most severely damaged areas were.

With the new shake map capabilities, it should be possible to know within the hour where emergency units are needed, Jones said.

Historic records show that California has, on average, about one potentially damaging quake of 6.5 magnitude or higher every four years.

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