GSC Open File Release Notices

45

An experimental high-sensitivity gamma-ray spectrometer survey was carried out by the Geological Survey of Canada in the Bancroft area of Ontario in 1969. Results have been compiled for an area of approximately 400 square miles, bounded by Lat. 44º51’ and 45º15’N, Long. 77º48’ and 78º05’W. Because of the large quantity of inter-related data this information will not be published in the usual manner but it has been prepared to publication standard.

The release comprises: Profiles for 61 flight lines at a scale of 1:250,000 and seven contoured radiometric maps on a scale of 1:50,000.

Each profiles shows the following measurements plotted against distance, corrected where relevant for atmospheric background, deviations from the nominal terrain clearance, and Compton scattering:

Integral (i.e. wide spectrum) count rate

Potassium count rate

Uranium count rate

Thorium count ratio

Uranium: thorium ratio

Uranium: potassium ratio

Thorium: potassium ratio

Terrain clearance

The radiometric maps are also fully corrected and relate to each of the parameters (1) to (7) listed above. Each one is reproduced on a base showing individual flight lines and the principal geographic features in the area, together with an explanatory paragraph.

The maps are intended to provide an overall picture of the radiometry of the area, whilst the profiles are most useful for information about specific localities. All profiles and contours have been computer plotted.

Examination Points: GSC Libraries in Ottawa, Calgary and Vancouver. Copies available from Campbell Quickprint, Ottawa