Applications of Analytic Theory for Neutron-Gamma-Ray
Spectra from Formation Elements
PANG Ju-feng, LI Min

The analytic theory and methods for the neutron-gamma-ray spectra from formation elements logging are used. The neutron-gamma-ray spectra are acquired continuously in four wells of two oil fields. The software system developed is used for continuous processing. The changing curves with the well depth for the quality fractions of H、C、O、Si、Ca、Fe、Mg、Al and the new C/O, new Ca/Si values are obtained,. even if the logging curves. The new C/O values are used to compute the oil saturability related well sections formations and the water hiding levels are divided. The quality fractions of elements are used to compute the minerals contents, density, macroscopic capture cross sections and permeability in formations