Selway-Bitterroot (ID-MT)

Survey type M-Dz (magnetic; digitized from contour maps)
Flown by U.S. Geological Survey
Date flown 09/69
Line spacing 1.6 (km)
Altitude 3353 (m) by barometer measurement
Total distance 9,197 (km)
References
Counties Custer - Idaho - Lemhi - Valley - Missoula - Ravalli
Overlapping surveys

Data: Magnetic (M-Dz)