RENO, Nev.—The chance of a significant earthquake rocking the Reno-Sparks area over the next half century is on the rise, with a 67 percent likelihood a magnitude 6.0 will strike within 31 miles by 2060, a new report said Wednesday.

That's up from four years ago when the last report by the Nevada Bureau of Mines and Geology put such odds at 50 percent.

A quake that size could be expected to claim 78 lives and leave 900 people homeless, the bureau said. More than 5,000 buildings would be destroyed or badly damaged, with total damages of $3.7 billion.

Carson City has a 70 percent chance of such a quake by 2060 that likely would kill nine people and severely damage nearly 1,000 buildings.

Craig dePolo, a research geologist at the bureau, said actual damages and deaths depend on the depth, location and duration of an earthquake. The new report profiles 38 communities.

"It gives an idea of what is going to be needed," he said. "Right after an earthquake, you don't know what's out there and (response) time is critical."

"We just want people to look at the magnitude of them, to appreciate the seriousness of the situation," dePolo said.

Nevada, California, Alaska and Hawaii are the most active states for earthquakes.

Geologists agree a magnitude 7.8 is probably the most severe earthquake that could happen in Nevada, dePolo said. That's weaker than the 8.8 earthquake that hit Chile on Saturday, killing more than 790 people.
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The strongest earthquake recorded in Nevada was 7.3 in 1915 in Pleasant Valley, near Winnemucca.

A swarm of earthquakes just west of Reno in April 2008 produced one that was 4.7 magnitude, the biggest in Reno in more than 50 years.

In an earthquake, the best thing to do is to "duck, cover and hold" under a table or a desk, dePolo said. People should not hang heavy items above their beds.

When a 6.0 magnitude earthquake hit Wells in February 2008, a large television set landed in a baby's crib.

"Thank goodness the 3-week-old girl was out of town that night," dePolo said.

Odds of a 6.0 magnitude quake in the Reno area are 7.4 times higher than a quake in Wells, 340 miles east of Reno. For Wells, the probability of an earthquake was estimated at 9 percent within 50 years, said Jonathan Price, the Nevada bureau director and state geologist.

In setting earthquake probability levels, geologists study fault lines, where earthquakes have occurred and the movement of the Earth's crust, Price told the Washoe County Commission last week.

With global positioning stations covering western Nevada, he said scientists can measure the position of the earth's crust in real time with a great deal of accuracy.

The new data "is demonstrating very clearly that this part of Nevada is playing along with California as part of the big seismic hazards in the West," Price said.

That means earthquakes in the Reno-Carson region are largely related to the San Andreas Fault, where the Pacific plate on the west moves north from the rest of the continent.

Price said that "essentially every mountain range in Nevada is bounded on one side or another by an active fault."

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