40AR/39AR Ages from the East Bonnifield geologic map area, Fairbanks A-1, Fairbanks A-2, Healy D-1, and Healy D-2 quadrangles, Alaska
Description
40Ar/39Ar data from plutonic, dike, and alteration samples collected during geologic mapping of the eastern part of the Bonnifield mining district geologic map area in parts of Fairbanks A-1 and Fairbanks A-2 and Healy D-1 and Healy D-2 quadrangles yield results indicating the plutons, dikes, and a gold-bearing quartz vein in the Bonnifield Map area range from 85 to 95 m.y.