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UCLA seismologists are shaking things up with a new method that may allow scientists to predict earthquakes months in advance.

The team of scientists from Russia, United States, Japan and France included experts in pattern recognition, geodynamics and statistical physics. They have already successfully predicted two earthquakes, including the recent earthquake of magnitude 6.5 that struck San Simeon, Calif. in late December.

Short-term earthquake prediction is a field that has garnered little success; many scientists believe prediction is generally impossible.

“People have tried a wide range of methods for many decades and so far none of them have worked on a time scale shorter than a decade,” said John Vidale, interim director of the Institute of Geophysics and Planetary Physics at UCLA.

Reliable earthquake predictions could save millions of lives and billions of dollars in damages, as well as prevent ecological disaster.

Scientists heavily base earthquake predictions on subtle, but detectable signals that emerge before strong earthquakes. Scientists have studied a host of potential warning signals known as precursors, which include foreshocks and even weird animal behavior.

The team approached the problem of earthquake prediction as one of pattern recognition. The goal was to find precursory patterns of medium and low magnitude earthquake sequences that could signal a larger earthquake in the future, said Vladimir Keilis-Borok, the team’s leader and professor in residence at IGPP.

The researchers looked for patterns reflecting a rise in earthquake occurrences and earthquake clustering in space and time.

The team also looked for simultaneous occurrences of earthquakes at increasing distances, and a rise in the ratio of medium magnitude earthquakes to smaller earthquakes.

The detection of these patterns is utilized by the team to make their predictions.

Predictions made decades before the actual quake are known as long-term, while intermediate-term predictions are made years in advance. Those made months before are called short-term, and immediate predictions come within days or less.

Precursors are also divided by the same time intervals. Previous studies looked for intermediate-term precursors to determine the possibility of a large earthquake.

“In the new approach we study short-term precursors in conjunction with intermediate-term ones,” Keilis-Borok said.

The team considered a chain of earthquakes as a possible short-term precursor. In the area where a chain emerged, researchers looked for intermediate-term precursors.

“If they were present, the chain is recognized as actual precursor, and a nine-month alarm starts for that area,” Keilis-Borok said.

If no intermediate-term precursors were present, then the chain of earthquakes was disregarded.

In July 2003, the team used this method to predict an earthquake in Japan of magnitude 7 or higher by the end of December. A magnitude 8.1 earthquake struck Hokkaido in late September.

With two successes and no misses, the team plans to continue testing and collecting more data to improve their prediction method.

Most seismologists are taking a wait-and-see attitude.

“Ordinarily, I wouldn’t believe it for a minute, but since his first two guesses are right, we have to take this seriously,” Vidale said.

“This appears to have some preliminary successes, but no one is sure yet and time will tell,” said professor of geophysics Emily Brodski.

The group is reluctant to release earthquake predication dates to the general public for fear of panic and economic damage, but they are watching for a magnitude 6.4 or higher earthquake by September south of the Mojave Desert.