Shaking Presaged Large California Earthquakes
Alaska and California have more earthquakes and more strong quakes than any other U.S. states. But depending on whether they count total number of quakes or the strongest temblors, geologists don't agree on ranking beyond that.
So John Anderson and Yuichiro Miyata at the University of Nevada, Reno, decided to investigate and create a formal list. Their Top 10 states, based on the greatest magnitude achieved every year:
- Alaska, 6.70
- California, 6.02
- Nevada, 5.11
- Hawaii, 5.00
- Washington, 4.97
- Wyoming, 4.67
- Idaho, 4.57
- Montana, 4.47
- Utah, 4.29
- Oregon, 4.24
The list is far from reflecting the quake risk in many locations. For example, the Midwest is prone to infrequent but powerful quakes, and sooner or later one will strike that is liable to wreak havoc across vast regions. Washington and Oregon, while not at the top of the new list, are both capable of suffering catastrophic damage in mega-quakes that could near or exceed magnitude 9.0.
"The reason for talking about this is not to change the rankings or to have one state move ahead of another—it's to motivate people to build structures that resist earthquakes," Anderson said. "If you're on this top-10 list, hopefully it will motivate you to be better prepared in the event of a large earthquake."
The study, published in the November/December issue of Seismological Research Letters, is based on actual quake accounts from 1568 to 1989 and seismological data from 1898 to 2005.