N.G.V. - Northwest (CA)

Survey type M-Dz (magnetic; digitized from contour maps)
Flown by Fairchild Aerial Surveys, Inc.
Date flown 10/51-03/52
Line spacing 1.6 (km)
Altitude 1372 (m) by barometer measurement
Total distance 804 (km)
References
Counties Shasta - Tehama
Overlapping surveys

Data: Magnetic (M-Dz)