An agency trying to predict earthquakes has developed a system to give warnings of another geological hazard: landslides, which kill 25 to 50 Americans and cause up to $2 billion in damage each year.

The experimental system so far has been used only in the San Francisco Bay area.But it is meant to demonstrate the possibility of issuing such warnings elsewhere in the nation so people in slide-prone hilly areas can evacuate if necessary, U.S. Geological Survey geologist Raymond Wilson said Thursday.

Wilson likened landslides to "a runaway freight train going through a neighborhood."

"It's a national problem," said David Keefer, leader of the agency's landslide research group. "Total U.S. landslide damages are estimated at somewhere between $1 billion and $2 billion a year," with 25 to 50 Americans killed annually.

"Landslide damages (in the United States) are larger on an annual basis that earthquake damage or volcano damage," he added.

They spoke at the Geological Survey's Geohazards '88 symposium, which drew about 250 scientists and public officials.

The warning system was tested successfully on Feb. 14, 1986, when a severe rainstorm prompted the Geological Survey and National Weather Service to warn that mudslides were possible during a six-hour period for much of the Bay area.