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Abstract Airborne gamma-ray spectrometry (AGS) is essentially a remote sensing technique since short-wavelength bands of the electromagnetic spectrum are measured by detectors and sensing such as optical and thermal remote sensing in that point measurements are collected along closely spaced flight lines and the data are interpolated to create images with a regular cell size. AGS, also known as ”gamma radiometrics” or ”radiometrics” in geology circles, uses gamma-ray emission in multiple wavelengths (typically 256) to derive abundances of the major gamma-emitting elements : potassium (K). thorium (TH) and uranium (U). This conversion to element abundances is necessary since in practices gamma-ray spectra are mixtures of the emissions of these three elements due to an effect known as Compton scattering. As such, the display of wavelength-range counts, such as in optical remote sensing, is of little value. The derived element concentrations provide spatial images of the geochemistry of the upper rock/soil layer to a depth of about 30-45 cm, largely passing through vegetation. Although lacking in depth of penetration compared to some geophysical techniques, the distribution of these element concentrations at the surface can often be related to subsurface properties. the information are presented as images. It differs from other traditional forms of remote. |