Survey number: AK14 and AK15 (Pat Hill numbers)
Name: Baird Mtns - Ambler River & Survey Pass Area
Date flown: 1973 - 1975
Company: GeoMetrics
Flight specs: 0.75 - 1 mile, N-S, 1000 ft above ground.
Instrument: ?

Digitized by: Esther Castellanos, 9/86 - new Shungnak D3 quad added by Saltus
                                         10/96
Map scale: 1:63,360 

Datum: 56188.10 nT at 66.75N and 161W (SW corner of survey)
       A planar regional trend was removed from each 1:63,360 quad using
       the 1965 IGRF updated to the year of the survey (1973, 1974, and 1975).
       In the SW corner of the map this regional trend was 
       3.85 nT/mile north and 2.26 nT/mile east.

Publication: State of Alaska Open File maps

Data format: Ascii format, XYZ records 
             Longitude (degrees), Latitude (degrees), Total Field (nT)
             written with FORTRAN format: (f10.5,x,f10.5,x,f8.1)

Background: These data were digitized under the direction of Rick Saltus 
            (saltus@usgs.gov) as part of the USGS project to merge the best 
            available aeromagnetic data into a consistent grid for the state 
            of Alaska.