Probe to measure material properties in borehole - determines electrical conductivity natural radioactivity and neutron gamma intensity

摘要

The probe measures electrical conductivity, natural radioactivity and neutral gamma intensity and contains a sealed gamma intensity meas. cell (11) whose outer wall forms a steel probe shaft (7) containing gamma detectors (1) and an amplifier. The shaft has an insulating sleeve (8) containing pref. lead electrodes (9, 10). The wires from inside the meas. cell to the outer electrodes are embedded in the insulating sleeve. The natural gamma detector (1) is in the upper half of the probe and the neutron gamma intensity detector and the neutral source are in the lower half of the probe. The probe surfaces are protected by a protective layer of plastics.