SAMPLING PROCESS OF RADIOACTIVE ROCKS AND ORES BY THEIR NATURAL GAMMA RADIATION Russian patent published in 1997 - IPC

FIELD: sampling of radioactive rocks and ores in rock outcrops, in workings, when sampling broken rock in transportation flows. SUBSTANCE: sampling section is localized by means of screen, intensities of radiation with and without screen are measured in presence of additional screen positioned on surface of examined rock or ore. In this case dimensions of screen in plan are equal to dimensions of localized section of sampling, and thickness of screen in any point of it is found by formula d(x_i,y_i) = lnP(x_iy_i,h,m)P(x_i,y_i,h,m)/μρ, where and are present coordinates of point for which calculation of thickness is conducted; and are coordinates of boundary of informative region in i-th section perpendicular to planes x and y; P(x_i, y_i, b, m) is weight function of detector for radiator placed in point with coordinates and , sr.m; is weight function of detector for radiator placed in point with coordinates on boundary of informative region in section passing through point with coordinates , sr.m; μ is mass coefficient of absorption of gamma radiation emitted by radioactive sources in examined rock or ore, kg/sq. m; r is density of material of screen, kg/cu.m; h is height of position of center of detector above radiating surface, m; m is half-length of detector, m. EFFECT: increased functional reliability.