Air-borne measurements of effective ground conductivity at low frequency in Alaska

Air-borne field strength measurements have been made over large sections of the Territory of Alaska in the frequency range of 203 kc to 407 kc. Theoretical field strengths are computed after the methods presented by K.A. Norton for both a plane and spherical single-layered earth and the theoretical values are compared with experimental data to obtain the effective ground conductivity. A discussion of the method of analysis is presented, and a map of the effective conductivity of wide regions of the Territory is included. The effective conductivity is shown to be between 0.5 and 5 mmho/m over most sections of Alaska.