Clear Lake '72 (CA)

Survey type M-Dz (magnetic; digitized from contour maps)
Flown by U.S. Geological Survey
Date flown 05/72
Line spacing 1.6 (km)
Altitude 1372 (m) by barometer measurement
Total distance 1,680 (km)
References
Counties Colusa - Lake - Mendocino - Napa - Sonoma
Overlapping surveys

Data: Magnetic (M-Dz)