中国石油大学学报（自然科学版）2018，Vol.42Issue(1)：60-66,7.DOI:10.3969/j.issn.1673-5005.2018.01.007
基于X射线和伽马源的密度测井数值模拟
Numerical simulation of density logging based on X-ray and gamma ray sources
摘要
Abstract
The attenuation coefficient of photoelectric absorption and Compton scattering for different energy rays with the me-dium are calculated and analyzed by XCOM.The Monte Carlo method is used to compare the scattering spectrum, the re-sponse of density logging,and the precision of X-ray and Cs-137 sources. The results show that because the X-ray energy is lower than that of the 0.662 MeV gamma rays,the X-ray attenuation is faster in the same formation, and this difference is more obvious withincreased density. At the same source-detector distance, the sensitivity to the density of the lower energy X-ray source is higher than that of the Cs-137 source, but is dependent on lithology.Considering the source intensity,when the source-detector distance is 33 cm for the X-ray source and 38 cm for the Cs-137 source,respectively,the counting statis-tics is equal between the two sources.The sensitivity to the density of the X-ray source is higher than that of the Cs-137 source,and the uncertainty of density measurements of the X-ray source is lower than that of the Cs-137 source,which indi-cates that the density logging precision of the X-ray source is higher than that of the Cs-137 source. It is concluded that X-ray source can replace gamma ray source for density logging,but further research in instrument design,energy spectrum process-ing and density calculation is needed.关键词
X射线源/伽马源/密度测井/衰减系数/蒙特卡罗方法Key words
X-ray source/gamma ray source/density logging/attenuation coefficient/Monte Carlo method分类
天文与地球科学引用本文复制引用
张锋,李亚芬,信毅,苏波,吴赫,张泉滢,刘军涛..基于X射线和伽马源的密度测井数值模拟[J].中国石油大学学报（自然科学版）,2018,42(1):60-66,7.基金项目
国家自然科学基金项目(41374125,41574119) （41374125,41574119）
国家科技重大专项(2017ZX05019005-005) （2017ZX05019005-005）
中央高校基本科研业务费专项(14CX05011A,15CX06008A) （14CX05011A,15CX06008A）
