抄録
In the logging methods which make the energy spectral analysis of gamma ray radiated from a formation, the accuracy of logging device is strongly affected by a gain stability of down hole scintillation gamma ray detector. The gain of the detector changes in a wide range in accordance with the formation temperature as the nature of the scintillation gamma ray detector. Therefore, a gain drift compensation system for such gain drift of the detector should be equipped in the logging device.
The method of gain drift compensation described in this paper is achieved by the combination of a reference isotope which is attached to a high-temperature scintillation gamma ray detector (120°C) and a gain drift indicator equipped at the surface control panel.
