Identification of gas reservoirs and determination of their parameters by combination of radioactive logging methods
© V.V. Kulyk, M.S. Bondarenko, 2016
The paper proposes a new approach for using a combination of radioactivity logging (neutron and density logging), which allows
determining a set of gas reservoir parameters (nature of saturation, true porosity, gas saturation) taking into account influence of
the pressure and temperature conditions of occurrence. Analysis of the ways of averaging the neutron-apparent porosity and the
density-apparent porosity for obtaining the true porosity was made. Method of determination of gas saturation, which uses the
same combination of radioactivity logging as in determining the true porosity of gas reservoirs, was developed. The results
presented in the paper, were obtained over a wide interval of depth (up to 10 km). Application of developed approaches for
determination of petrophysical parameters of gas reservoirs is demonstrated by the example of cased coalbed methane well.
Key words: gas reservoirs, pressure-temperature conditions of occurrence, combination of neutron logging and density logging,
identification of gas reservoirs, apparent porosities, true porosity, gas saturation.