Canada - Radiometric survey data compilation

The data presented in the radioactivity map of Canada series (Buckle et al., 2014) depict the surface concentrations of three naturally-occurring radioactive elements: potassium (K, %), equivalent uranium (eU, ppm), and equivalent thorium (eTh, ppm); as well as five derived products: natural air absorbed dose rate (NADR, nGy/h) calculated from a linear combination of potassium, equivalent uranium, and equivalent thorium concetrations; the ratios eU/eTh, eU/K, and eTh/K; and the ternary map which uses false colour to illustrate the co-variation of the three measured elements (Broome et al., 1987). This compilation was produced with data from more than 370 airborne gamma-ray surveys flown or supervised by the Geological Survey of Canada between 1969 and 2011. Data was calibrated and acquired in accordance to standards in effect at the time each survey (see Darnley et al., 1975 and IAEA, 1991). Most of the data was acquired using 50 L of Sodium Iodide (NaI) detectors flown at a nominal terrain clearance of 120 m, but line spacings vary from 5000 m to 200 m depending on the specific survey. Potassium is measured directly from the 1460 keV gamma-ray photons emitted by Potassium-40.…

Publisher

Natural Resources Canada

Resources

32

Catalogue metadata updated

2020-05-05