1927 North American datum.
Relief shown by contours and spot heights.
Topography from aerial photographs by photogrammetric methods for the Bureau of Reclamation 1948 and by the Geological Survey 1954. Aerial photographs taken 1947-1949. Field check 1955.
1955.
N4500-W11045/15.
Land lines unsurveyed in parts of T. 9 S.-Rs. 6, 7, and 8 E.