Quakes rattling Reno may be prelude, scientists warn

Scientists urged residents of northern Nevada’s largest city to prepare for a bigger seismic event as the area continued rumbling Saturday after the largest in a two-month-long series of earthquakes.

More than 100 aftershocks were recorded on the western edge of the city after a magnitude 4.7 quake hit Friday night, the strongest in the Reno area since one measuring 5.2 in 1953, according to researchers at the seismological laboratory at the University of Nevada, Reno.

The latest quake swept store shelves clean, cracked walls in homes and dislodged rocks on hillsides, but there were no reports of injuries or major widespread damage.

Seismologists said the recent activity was unusual because the quakes started out small and continue to build in strength. The normal pattern is a main quake followed by smaller aftershocks.

“A magnitude 6 quake wouldn’t be a scientific surprise,” John Anderson, director of the seismological lab, said Saturday. “We certainly hope residents are taking the threat seriously after last night.”

But Anderson stressed that there was no way to predict what would happen, and said the sequence of quakes also could end without a major one.

Reno’s last major earthquake measured 6.1 on April 24, 1914, and was felt as far away as Berkeley, said Craig dePolo, research geologist with the Nevada Bureau of Mines and Geology.

A rock slide triggered by Friday night’s quake was blamed for a 125-foot breach in a wooden flume that carries water to one of two water treatment plants in Reno, a city of about 200,000.

A backup pump was used to divert water to the plant, and the breach was not expected to cause any water shortages, said Aaron Kenneston, Washoe County emergency management officer.

The U.S. Geological Survey said Friday night’s quake was centered near Mogul, just west of Reno.