Steve Quayle News Alerts

Jan. 9, 2004
By Amit Asaravala

Seismologists may soon have the ability to predict earthquakes several months in advance, say a team of researchers at the University of California at Los Angeles.

The group announced Tuesday that it had used a newly developed technique to closely forecast major earthquakes in California and Japan last year, including the magnitude 6.5 tremor that struck Paso Robles, California, in December, and the magnitude 8.3 quake near Hokkaido, Japan, in September.

The team has submitted a paper outlining the technique to Physics of the Earth and Planetary Interiors, an international geophysics journal.

Seismologist Vladmir Keilis-Borok, who is the lead researcher on the project, called the advancement a "major breakthrough."

"Short-term prediction was considered impossible by many," said Keilis-Borok. "We have built on the work of scientists from all over the world to show that it can be done."

The team's new method differs from existing techniques in that it takes into account the small "chains" of tremors that often occur before a major earthquake.

When a long chain of related earthquakes is discovered in a region, the team analyzes the area's history, in search of various seismic patterns. If other patterns are discovered, the group announces a nine-month forecast.

Although the new method does not yet allow seismologists to pinpoint the exact date and time of future earthquakes, the UCLA researchers say it lets them narrow their forecasts to a range of several months.

For instance, in June 2003, the team predicted that a magnitude 6.4 quake would hit the Central California region within nine months. The 6.5 magnitude Paso Robles quake struck on Dec. 23.
In July 2003, the team made a similar prediction for the northern portion of Japan, saying that a magnitude 7 or greater earthquake would occur sometime in the next nine months. The 8.3 magnitude Hokkaido quake hit on Sept. 25.

In both cases, earthquakes of similar magnitudes had not been detected in the regions for years.
"There is very little chance of coincidence," said Keilis-Borok. "We look for chains as a way to determine short-term precursors. But we also use accepted intermediate-term methods to eliminate alarms from chains that occur by chance."

Although the group is currently researching earthquake patterns in California, Japan and the Middle East, Keilis-Borok said his team had not yet analyzed any information for the region near Bam, Iran, where a magnitude 6.6 earthquake last month killed tens of thousands of people.

Accurate short-term earthquake prediction has long been the holy grail of seismology. However, many researchers have focused their attention on other areas after a number of disappointing results over the past two decades.

For that reason, some seismologists are adopting a wait-and-see attitude toward the new findings.
"The seismological community is split at the moment," said seismologist Jim Dewey of the U.S. Geological Survey. "Half don't think earthquake prediction is possible, and the other half varies from being optimistic to being able to see how a breakthrough might one day change the field.

"The real question, though, is: What will you do if this method is accurate?" added Dewey. "If it's scientifically correct, then it's a scientific breakthrough. But in terms of time range, it's too short to change building codes and too long to evacuate people."

Harvard professor of structural and economic geology John Shaw agreed that if the new method proves to be accurate, those who plan to use it should carefully evaluate their goals.

"The progress that's being made so far is on two time scales: decades, and tens of seconds," said Shaw. "With forecasts that span a decade, we can change the way buildings are built. And with the early-warning systems that we're working on, we can shut off gas lines and other utilities right before a big earthquake.

"The goal is to focus on the buildings," he added. "Because buildings are obviously what kill people, not the earthquakes themselves."

Keilis-Borok says he hopes the research will help prove that earthquake prediction can be possible, especially with further advancements. He also hopes that the predictions will allow communities to prepare their emergency-response teams.

"We are working with the appropriate authorities every time we make a prediction," said Keilis-Borok. "That way, they can decide how best to use that information."

The UCLA team plans to continue testing its predictions against future earthquakes to verify the accuracy of the method.

Although the group prefers not to announce predictions to the public for fear of causing panic and economic damage, UCLA did reveal in a press release Tuesday that the team is now watching for a possible 6.4 magnitude quake in a sparsely populated area south of the Mojave Desert sometime before Sept. 5.

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