摘要
采用氘-氚(D-T)可控源进行中子孔隙度测井时,其响应结果与化学源中子孔隙度测井的响应结果存在差异,使得传统化学源中子孔隙度测井的实验数据和解释模型难以适用。为了验证已有的密度校正方法是否能够用于中子孔隙度测井的结果校正,使D-T源与化学源的响应结果相接近,本文通过模拟获取不同孔隙灰岩含水地层和泥岩中的响应结果,将模拟结果与研制的实验装置测量结果进行基准检测,然后分析D-T源中子孔隙度测井校正前后与化学源中子孔隙度测井对比的响应差异,并利用实际测井数据验证可控源孔隙度测井方法的有效性。结果表明:经过密度校正后,可控源与化学源中子孔隙度的测量结果有较好的相似性,在实际测井曲线上两者也存在较好的对应关系。因此,本研究对于验证可控源中子孔隙度测井方法的有效性和今后测井仪器中放射源的可兼容替代有一定的应用意义。
[Background]In neutron porosity logging,different response exists when use D-T source to replace chemical source to measure porosity,which makes the experimental data and interpretation model of traditional chemical source neutron porosity logging difficult to apply.[Purpose]This study aims to verify whether the existing density correction method can approximate the response of neutron porosity logging with D-T source instead of chemical source.[Methods]First of all,response results of water saturated limestone formations with different porosity and different mudstone were obtained by simulation calculation using Monte Carlo N-Particle Transport Code(MCNP),and benchmarked the simulation results with the experimental device measurements.Then these differences among D-T source's raw data,the D-T source's corrected data and chemical source's data were compared and analyzed.Finally,actual logging data were used to validate the effectiveness of the controlled source applicable to neutron porosity logging.[Results]After density correction,the results of porosity logging of the controlled source are similar to that of the chemical source,and good correspondence between the two results are found in their actual logging curve.[Conclusions]This study has certain application significance for verifying the validity of control source for neutron porosity logging and the compatible substitution of radioactive sources in future logging tools.
作者
杨宁宁
YANG Ningning(Measurement and Control while Drilling Technology Center of Sinopec Oilfield Service Corporation,Dongying 257078,China)
出处
《核技术》
CAS
CSCD
北大核心
2020年第4期90-94,共5页
Nuclear Techniques
基金
国家科技重大专项(No.2016ZX05021-001)
国家重点研发计划(No.2016YFC0302802)资助。
