中国石油大学学报（自然科学版）2017，Vol.41Issue(4)：78-84,7.DOI:10.3969/j.issn.1673-5005.2017.04.010
随钻中子伽马密度测井的双源距含氢指数校正方法
Dual-spacing hydrogen index correction method for neutron gamma density measuring in LWD
摘要
Abstract
To resolve unstable density measurements using single detector hydrogen index correction calculation in neutron gamma density logging, a dual-spacing hydrogen index correction method is studied. The neutron and gamma ray distribu-tion in different hydrogen index and formation conditions is simulated by a Monte Carlo method. A hydrogen index correc-tion calculation model is established by the dual-spacing count rate ratio of capture gamma ray, hydrogen capture gamma ray and thermal neutron. The results of hydrogen index correction and the impact of caliper and salinity are compared. As a result, the accuracy in the density measurements after hydrogen index correction has improved significantly. Among them, the precision and accuracy from thermal neutron correction is the highest. The accuracy from hydrogen capture gam-ma correction is slightly higher than that of the capture gamma; on the contrary, the precision of hydrogen capture gamma is far less than that of the capture gamma and the thermal neutron. The error of dual-spacing hydrogen index correction in-creases with the increasing caliper and salinity. The results from thermal neutron correction are less sensitive to caliper and salinity, while the results from capture gamma and hydrogen capture gamma correction are considerably are on the oppo-site. The research provides correction methods for obtaining neutron gamma density accurately in LWD.关键词
可控中子源/双源距/密度/含氢指数/蒙特卡罗模拟Key words
pulsed neutron source/dual-space/density/hydrogen index/Monte Carlo simulation分类
天文与地球科学引用本文复制引用
张泉滢,张锋,王玉伟,刘军涛,贾文宝,遆永周,李静..随钻中子伽马密度测井的双源距含氢指数校正方法[J].中国石油大学学报（自然科学版）,2017,41(4):78-84,7.基金项目
国家自然科学基金项目(41374125,41574119) （41374125,41574119）
国家重大油气专项(2017ZX05019005-004) （2017ZX05019005-004）
中央高校基本科研业务费专项(14CX05011A,15CX06008A) （14CX05011A,15CX06008A）
