METHOD FOR SELECTING BRINE-BEARING AND BRINE-ABSORBING INTERVALS IN GEOLOGICAL SECTION OF WELLS OF OIL AND GAS CONDENSATE FIELDS Russian patent published in 2023 - IPC E21B47/10 G01V5/14 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to nuclear-physical methods of geophysical well surveys for identifying inter-salt and pre-salt intervals of a section of cased oil and gas wells containing brine, dividing them into brine-bearing and brine-absorbing layers, as well as identifying intervals of cement stone voids filled with brine. The method for identifying brine-bearing and brine-absorbing intervals in the geological section of wells of oil and gas condensate fields includes well surveys at two stages: during construction, regularly at the stage of operation. These stages are characterized by different geological and technical conditions and are taken into account when using nuclear physics methods: gamma ray logging, spectrometric gamma ray logging, neutron gamma ray logging, two-probe neutron-neutron logging for thermal neutrons, two-probe pulsed neutron-neutron logging for thermal neutrons, revealing features of the geological section immediately after drilling, the state of the formations and cement stone after casing of the well, and later, periodically at the stage of operation. Comparison of the results of measurements with probes of a number of nuclear physics methods obtained at different stages of well construction and operation makes it possible to estimate the exact boundaries of brine-bearing and brine-absorbing intervals, as well as to identify intervals of cement stone with voids filled with brine.

EFFECT: functionality of the number of nuclear physics methods is extended to identify intervals in a section of cased oil and gas wells containing brine, to separate brine-bearing and brine-absorbing intervals, and to identify intervals with brine in cement stone in a section of cased oil and gas wells.

1 cl, 2 dwg