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Portola Valley, just south of San Francisco, is famous for its progressive approach to geology. The town was the subject of the first geologic map of California and the first municipality in the state to hire its very own resident geologist. There’s a good reason: The section of the San Andreas Fault that produced the deadly San Francisco quake of 1906 runs right through the town. But where exactly the fault trace lies has long been a mystery. Now, in a new study, researchers have used a combination of new technology and old photographs to relocate the fault line.

If rules are made to be broken, then perhaps conventional wisdom is made to be overturned. The spate of large earthquakes in recent years — the magnitude and location of which have defied scientific expectations in several cases — has provided ample support for these maxims, at least within earth science. For all the confusion, though, data emerging from these events are reshaping and improving our understanding of how faults operate.

Earlier this week, an Italian judge summarily convicted seven participants in a meeting of the Italian Serious Risks Commission who evaluated the hazard posed by the L’Aquila earthquake swarm before the magnitude-6.3 earthquake on April 6, 2009, for the same offense and to the same penalty: six years in prison. Much has been written about this court decision, but the very different roles played by the seven defendants and their different expertise have not been discussed. Is there no difference among the roles of the “L’Aquila Seven” in the communication disaster?

Although seismologists and engineers have generated a world map of seismic hazard, which shows the level of ground shaking not likely to be exceeded, the ground motions and death tolls of several recent large quakes have far exceeded expectations. It’s time to change the way we measure seismic hazard and seismic risk.