FIELD: physics.
SUBSTANCE: to compensate for the photoelectric effect in pulsed gamma-ray density logging devices, steps are carried out for: creating a source of high-energy particles and directing said particles into a formation having known photoelectric absorption coefficient and electron density; one or more photons emitted from or deviating from the formation are captured with one of a first and a second detector, where the first detector lies at a first distance from the source, the second detector lies at a second distance from the detector, and a third distance separates the first detector from the second detector; first total energy of said one or more photons falling on the first detector over a time interval is measured, and second total energy of one or more photons falling on the second detector over the same time interval is measured; a first filter is placed between the first detector and the formation so that sensitivity to photoelectric absorption matches deviation of the device, thereby compensating for both effects simultaneously.
EFFECT: enabling simultaneous compensation for interactions caused by photoelectric effect and density variations caused by device deviation.
46 cl, 16 dwg
