NOTES for regional corrections Regional generated from USGS model USCON95 from the following parameters 39.7667,-105.237 -> 54400 nT 39.7667,-105.222 -> 54402 nT 39.7621,-105.237 -> 54397 nT 39.7621,-105.222 -> 54399 nT All field intensity values computed at an elevation of 5800 ft