This has been my one reliable indicator of Oklahoma earthquake activity. It's always right, except now at the end of the year, there is the issue of gas-frack freeze-up. In any normal year, I'd say we'd have to wait until May to restart the season, but it is so warm that they may still be fresh-water fracking for a while yet.
Meanwhile, OK is perking up again for another big one. These natgas prices will help things along.