THE RESEARCH OF HIGH RESOLUTION NEUTRON CAPTURE GAMMA RAY SPECTRUM LOGGING

This article discusses the principle of the neutron γ capture logging and the calculating method for element’s concentration,including two basic problems,i.e.the deriving of the equivalent, relative detection efficiency,η_（Eγ） and the deducting interference of the elements,Fe,Ti,and H from the probe case and borehole liquid.We run several borehole coal logging in Shandong Province.The comparation between logging and chemical analysis show better results than PGT’s,Schlumberger’s and GLT’s of U.S.A.The article also introduces the specturums from continuing measuring, which provide lots of geological informations and logging curves, such as S₅₁₁,S_B and S_H/S_b （that never have be been before ） after processing.