Alaska is followed by California. But beyond that point, depending on how you measure activity, the rankings change.
The rankings, based on the magnitude of earthquakes that occurs once per year on average: 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; and Oregon, 4.24.
"The reason for talking about this is ... to motivate people to build structures that resist earthquakes," said NSL Director John Anderson. "If you're on this Top 10 list, hopefully it will motivate you to be better prepared in the event of a large earthquake."
Anderson and colleague Yuichiro Miyata analyzed the U.S. Geological Survey's Advanced National Seismic System's catalog of earthquakes, which contains data from 1898-2005. The researchers supplemented that with data from the USGS catalog of significant U.S. earthquakes from 1568-1989.
The research appears in the November/December issue of the journal Seismological Research Letters.