Multi-function Neutron Imaging System (MNIS)

The FSI MNIS was invented and developed by Frontier Sonde Inc. The system innovatively integrates advantages of neutron-gamma and neutron-neutron tools and surmounts disadvantages of both these tools. Based on measurements of multi-dimensional parameters and imaging of neutron die-away time spectra, MNIS can provide a broader service range compared to other tools on the market. The system can be applied to high/medium/low-salinity and high/medium/low-porosity formations. Gas layers can also be qualitatively identified. In order to enhance the system's sensitivity to oil/gas/water layers, FSI's professionals have performed numerous Monte Carlo simulations and worked out the most optimal design for the inner construction of the tool. Consequently, the optimised sensor array arrangement improves measurement sensitivity of the system. In addition, all the key components of the system such as the pulsed neutron generator and nuclear sensors were manufactured in the United States. These reliable, high-performance and long lifetime components enhance our high-quality products.

The MNIS uses a pulsed neutron generator, emitting 14 MeV fast neutrons at a certain repetition rate and frequency. The fast neutrons then interact with formation elements in a variety of interactions such as inelastic and elastic scatterings. In the slowing-down process, each neutron loses it's energy and becomes a thermal neutron with lower energy. Those thermal neutrons are absorbed by formation nuclei, usually simultaneously emitting capture gamma rays. Gamma rays and thermal neutrons that are not captured bear formation information. A neutron and gamma ray sensor array is used to simultaneously measure neutrons and gamma rays at a certain time interval (die-away time spectra) to indicate gas and calculate water saturation.