Earthquake forecast program has amazing success rate

Gretchen Cook-Anderson
Headquarters, Washington Oct. 4, 2004
(Phone: 202/358-0836)

Alan Buis
Jet Propulsion Laboratory, Pasadena, Calif.
(Phone: 818/354-0474)

Andy Fell
University of California, Davis, Calif.
(Phone: 530/752-4533)

RELEASE: 04-327

EARTHQUAKE FORECAST PROGRAM HAS AMAZING SUCCESS RATE

A NASA funded earthquake prediction program has an amazing track
record. Published in 2002, the Rundle-Tiampo Forecast has accurately
predicted the locations of 15 of California's 16 largest earthquakes this
decade, including last week's tremors.

The 10-year forecast was developed by researchers at the University of
Colorado (now at the University of California (U.C.), Davis) and from NASA's
Jet Propulsion Laboratory (JPL), Pasadena, Calif. NASA and the U.S.
Department of Energy funded it.

"We're elated our computer modeling technique has revealed a relationship
between past and future earthquake locations," said Dr. John Rundle,
director of the Computational Science and Engineering initiative at the U.C.
Davis. He leads the group that developed the forecast scorecard. "We're
nearly batting a thousand, and that's a powerful validation of the promise
this forecasting technique holds," he said.

Of 16 earthquakes, magnitude 5 and higher since Jan. 1, 2000, 15 fall on
"hotspots" identified by the forecasting approach. Eleven of the 15 quakes
occurred after the paper was published in Proceedings of the National
Academy of Sciences in Feb. 2002. The scorecard uses records of earthquakes
from 1932 onwards to predict locations most likely to have quakes of
magnitude 5 or greater between 2000 and 2010. According to Rundle, small
earthquakes of magnitude 3 and above may indicate stress is building up
along a fault. While activity continues on most faults, some of those faults
will show increasing numbers of small quakes, building up to a big quake,
while some faults will appear to shut down. Both effects may herald the
possible occurrence of large events.

The scorecard is one component of NASA's QuakeSim project. "QuakeSim seeks
to develop tools for quake forecasting. It integrates high-precision,
space-based measurements from global positioning system satellites and
interferometric synthetic aperture radar (InSAR) with numerical simulations
and pattern recognition techniques," said JPL's Dr. Andrea Donnellan,
QuakeSim principal investigator. "It includes historical data, geological
information and satellite data to make updated forecasts of quakes, similar
to a weather forecast," she said."

JPL software engineer Jay Parker said, "QuakeSim aims to accelerate the
efforts of the international earthquake science community to better
understand earthquake sources and develop innovative forecasting methods. We
expect adding more types of data and analyses will lead to forecasts with
substantially better precision than we have today."

The scorecard forecast generated a map of California from the San Francisco
Bay area to the Mexican border, divided into approximately 4,000 boxes, or
"tiles." For each tile, researchers calculated the seismic potential and
assigned color-coding to show the areas most likely to experience quakes
over a 10-year period.

"Essentially, we look at past data and perform math operations on it," said
James Holliday, a U.C. Davis graduate student working on the project.
Instrumental earthquake records are available for Southern California since
1932 and for Northern California since 1967. The scorecard gives more
precision than a simple look at where quakes have occurred in the past,
Rundle said.

"In California, quake activity happens at some level almost everywhere. This
method narrows the locations of the largest future events to about six
percent of the state," Rundle said. "This information will help engineers
and government decision makers prioritize areas for further testing and
seismic retrofits."

So far, the technique has only missed one earthquake, a magnitude of 5.2, on
June 15, 2004, under the ocean near San Clemente Island. Rundle believes
this "miss" may be due to larger uncertainties in locating earthquakes in
this offshore region of the state. San Clemente Island is at the edge of the
coverage area for Southern California's seismograph network. Rundle and
Holliday are working to refine the method and find new ways to visualize the
data.

Other forecast collaborators include Kristy Tiampo, the University of
Western Ontario, Canada; William Klein of Boston University, Boston; and
Jorge S. Sa Martins, at the Universidad Federal Fluminense, Rio de Janeiro,
Brazil.

For more information, images and updated scorecard maps on the Internet,
visit:

http://www.gsfc.nasa.gov/topstory/20...arthquake.html

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Jacques :-)

www.spacepatches.info