Nevada earthquake swarm not letting up
Nevada is proving why it is the third most seismically active state in the United States behind California and Alaska.
While it hasn’t had a magnitude 7.0 earthquake in 60 years, the far northwest corner of the state has been shaking for the better part of this fall. It all started in the summer.
There have been several 3.0 earthquakes this week, a 4.0 on Nov. 21 and a 4.3 on Nov. 17. The largest two events – magnitude 4.7 – occurred just after midnight Nov. 6 and Nov. 7.
The thousands of earthquakes in the last several months is the strongest of the swarm-type sequences recorded in Nevada in recent history with its current count of 12 magnitude 4.0-plus events since it began in July.
The area being inundated by these temblors is in the Sheldon National Antelope Refuge about 40 miles southeast of Lakeview, Ore., 40 miles northeast of Cedarville, Calif. and about 250 miles north of Reno. Farm, ranch and grazing lands dominate the landscape.
“We’ve located about 1,350 earthquakes, but thousands more that are taking place just can’t be located because of the small number of seismic stations in that part of the state,” Ken Smith, seismic network manager in the UNR’s Nevada Seismological Laboratory, said in a statement. “So far there have been 112 earthquakes greater than or equal to magnitude 3.0. We’d have to go back to a similar sequence near Hawthorne in 2011 and the 2008 west Reno swarm for anything comparable.”
Additional instruments are being added to the area in order for scientists to gather more data. The goal is to have a better understanding of earthquake swarm behavior.
Scientists said there is a small increase in the probability of a larger event because of the swarm, but forecasting such an earthquake is not possible.
The Wells earthquake in 2008 was a magnitude 6.0, the largest event in Nevada in 42 years. Historically, Nevada can expect to have three magnitude 7.0 earthquakes per century and one magnitude 6.0 or larger every decade, according to Graham Kent, director of UNR’s Seismological Lab, said in a statement.
— Lake Tahoe News staff report