Walton, M.S., Jr., 1947, Magnetic exploration of the nickel-copper deposits of Bohemia Basin, southeastern Alaska: New York City, New York, Columbia University, Teachers College, M.S. thesis.
The Bohemia Basin nickel-copper deposits are segregations of pentlandite, pyrrhotite, and chalcopyrite in the lower portions of a norite mass, the bottom of which is basin-shaped. Eight traverses were made with an Askania vertical intensity magnetometer across the projected position of the deposit beneath a covered area. Magnetic anomalies were observed at the inferred position of the deposit along six of the traverses and indicate that the body is continuous beneath most of the covered area. Magnetic profiles are consistent with the hypothesis, proven at two places by outcrops and drill holes, that the deposit dips inward. The profiles and outcrops indicate that the deposit averages about 80 ft thick. The profiles also suggest that the deposit under the covered area extends downdip for a distance greater than its thickness and that the muskeg cover is not deep. These inferences are consistent with available drill data. The inferred quantity of sulfide-bearing material in the deposits was increased by the results of magnetometer exploration from 5,000,000 tons to 8,500,000 tons. The magnetic data will facilitate planning of any future development of the deposits and would have been useful in the more effective placement of some of the holes already drilled.
Theses and Dissertations
