Development of a geochemical logging tool incorporating neutron time of flight techniques

Summary form only given. The authors discuss an experimental program to design an improved geochemical logging tool which uses nanosecond time-of-flight techniques. Specific elements are identified according to the energy of a detected inelastic gamma-ray and its arrival time relative to the emission of the responsible neutron. A key feature of the method is the recognition of individual source neutrons, which permits the use of both radioisotope and neutron generator sources, and imposes a degree of directionality that can improve borehole fluid discrimination. A laboratory feasibility study has been carried out, and computer modeling work with Monte Carlo codes has been performed.<>