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A seismologist trying to predict earthquakes by focusing on fault areas that have been quiet for centuries suggests that the northern Hayward fault on the east side of San Francisco Bay may be ripe for a significant temblor. 

Max Wyss of the University of Alaska, Fairbanks, contends that locked northern areas of the fault are capable of producing a magnitude 6.5 earthquake. That’s just shy of what seismologists call a major quake, one of magnitude 6.7 or greater. 

Wyss’ findings were published in the Sept. 15 issue of the journal Geophysical Research Letters. 

The Hayward fault runs northwest along the East Bay, from San Jose through Oakland and Berkeley to San Pablo Bay. The course of the fault runs through the University of California, Berkeley — down the middle of Memorial Stadium. 

A statewide team of seismologists in 1999 said the chances are roughly one in three that the Hayward fault will see a major earthquake in the next 30 years. 

Last year, a team led by UC Berkeley geophysicist Roland Burgmann concluded that the risk lies in the central and southern reaches of the fault, and that ground motion data collected by satellite shows that pressure is not building up along the northern end. 

Wyss theorizes that areas with a history of seismic activity that have been quiet for centuries are more likely to see big earthquakes than areas where small earthquakes are common. He said last week that the seismic history of other areas he has studied — including Alaska and Mexico — backs up that theory, but he has yet to predict an earthquake using the theory. 

The northern Hayward fault has seen relatively little seismic activity and no major quakes in recorded history, but scientists estimate a major earthquake hit there between 1640 and 1776. A major quake last hit the southern half of the fault in 1868. 

Wyss said the northern part of the fault appears to be locked, setting the stage for a great release of energy, but did not offer an estimate of when a quake might hit. 

Burgmann said that although he believes his team’s research remains valid, Wyss’ approach to earthquake prediction “has promise. ... The underlying assumptions do make sense.” 

Research using Wyss’ approach will need to be applied in more places for seismologists to better evaluate it, Burgmann said. 

The field is continually improving, Burgmann said, adding that he’s confident that scientists eventually will be able to “feel the pulse of the fault.”