Russian quake causes false temblor reports in California
A magnitude 7.7 earthquake in a sea off the coast of eastern Russia caused numerous "false positive" reports of earthquakes in California, a United States Geological Survey official said Monday night.
Leslie Gordon, USGS spokeswoman in Menlo Park, said the false reports of earthquakes in Gerber, the Monterey area and Gilroy were triggered by the Russian quake. Those reports were retracted within minutes, Gordon said. A couple of the reports were erroneously reissued, then retracted again.
False reports occasionally are registered by USGS automatic earthquake sensors, she said.
Those sensor reports are automatically transmitted to subscribers of the agency’s earthquake notification system. Within minutes, seismologists review every report and retract those few that are false, Gordon said.
“On rare occasions we’ll have these false positives," she said. "We figure that the risk is worth it.”
The other option, she said, is to hold each earthquake report until a seismologist reviews it.
“We don’t want to hold up every single notice until it’s reviewed by a seismologist. It would add 10, 20 minutes to every notice,” she said.
-- Sam Quinones