METHOD OF NEUTRON LOGGING FOR DETERMINATION OF URANIUM CONTENT IN URANIUM-ORE FORMATIONS CROSSED BY WELL Russian patent published in 2017 - IPC G01V5/10 

FIELD: oil and gas industry.

SUBSTANCE: recordings of count rate values of instantaneous fission neutrons and count rate values of thermal neutrons are obtained in a plurality of dots, count rate of instantaneous fission neutrons and thermal neutrons at each point of logging is determined in the decay processing, recordings of logging are obtained by secondary methods of well physical characteristics and uranium-ore formation reservoir, where the logging data are obtained by the emission of neutrons bursts with 14 MeV energy, that dissipate their energy to the level thermal ones, and epithermal instantaneous fission neutrons, emitted by uranium, are detected to fissionable thermal neutrons. At the same time, as a basis for calculating the uranium content, integral count rate of epithermal neutron detector is taken, which is brought to a single neutron flux by neutron flux monitor data, as a uranium content reference standard parametric well is used, certified in uranium-ore formation and ore-bearing thicker after uranium content, power, lifetime of thermal neutron in the formation, the above-mentioned standard stores and reproduces the set of physical characteristics of well and uranium-ore formation reservoir, a cycle of logging studies is conducted, which includes performing two instrumental checks of standard prior to logging of prospecting well and after logging of search well to obtain the average value of scalar coefficient, SC, estimated by a predetermined mathematical relation, which is used in the calculation of the uranium content in the cut, crossed by prospecting well.

EFFECT: reducing the error in estimating the uranium content.

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