Effects of line spacing on contoured airborne gamma-ray spectrometry data

A reconnaissance airborne gamma-ray spectrometer survey is usually designed to show the regional surface radioelement distribution pattern and locate broad areas of uranium enrichement. Perhaps the most important parameter to consider for this type of survey is the flight-line spacing which will give the desired information most economically. Airborne gamma-ray spectrometry data of equivalent uranium distribution have been computer contoured into maps to qualitatively illustrate the effect of varying the flight-line spacing between 400 m and 5 km. Data for two coincident surveys with perpendicular flight-line directions were also computer contoured. The results demonstrate that reconnaissance survey data, with line spacing as wide as 5.0 km can be contoured to show regional radioelement distribution patterns over the Canadian Precambrian Shield. This line spacing has been adopted for the airborne gamma-ray spectrometric part of Canada's Uranium Reconnaissance Program, a 10-year programme designed to collect systematic reconnaissance data for much of Canada. (author)