Temporal and spatial resolution of the neutron probe for C/O nuclear well logging

The potential of detecting particular formation elements inside boreholes, separated by small distances, was investigated. Neutron probe, designed for C/O nuclear well logging and with associated alpha particle method (AAP) as its operational principle, was used. The measurements consisted of irradiating 0.5 l diesel-filled plastic bottle with fast tagged neutron beam. The bottle was placed in four positions along the axis of the probe, spaced by similar to 10 cm; time spectrum for each position was obtained. The peaks in time spectra are separated by similar to 2 ns, suggesting that neutron probe with AAP can, in principle, distinguish between parts of the formation separated by 10 cm. The results were confirmed by Monte Carlo (MC) simulations of the experiment.

Automated summary

The potential of detecting specific formation elements separated by small distances inside boreholes was investigated in this study. The neutron probe, utilizing the associated alpha particle method (AAP) as its operational principle, was used for the measurements. The results suggest that the neutron probe with AAP has the capability to distinguish between different parts of the formation separated by 10 cm.