S. South Dakota (SD)

Survey type M-Dz (magnetic; digitized from contour maps)
Flown by Aero Service Corporation
Date flown ?/69-?/70
Line spacing 1.6 (km)
Altitude 1311 (m) by barometer measurement
Total distance 28,689 (km)
References
Counties Bennett - Custer - Haakon - Hughes - Jackson - Jones - Lyman - Meade - Mellette - Pennington - Shannon - Stanley - Sully - Todd - Ziebach
Overlapping surveys

Data: Magnetic (M-Dz)