Nuclear Techniques ›› 2020, Vol. 43 ›› Issue (1): 10503-010503.doi: 10.11889/j.0253-3219.2020.hjs.43.010503

• NUCLEAR PHYSICS, INTERDISCIPLINARY RESEARCH • Previous Articles     Next Articles

Numerical simulation of detecting characteristics of the spectral azimuthal γ-ray logging while drilling

Duo DONG1,Wensheng WU1(),Wenzheng YUE1,Jian ZHENG2,Hui GAO3,Lugang HUANG3,Junya DUAN3   

  1. 1. State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China
    2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
    3. Xi'an Huineng Electronic Equipment Co. , Ltd. , Xi'an 710065, China
  • Received:2019-01-09 Revised:2019-10-10 Online:2020-01-15 Published:2020-01-21
  • Contact: Wensheng WU E-mail:wwsheng@cup.edu.cn
  • About author:DONG Duo, male, born in 1991, graduated from China University of Petroleum (East China) with a master's degree in 2016, doctoral student, focusing on nuclear logging technology
  • Supported by:
    Chinese Academy of Sciences Class A Strategic Pilot Technology Program(XDA14020600)

Abstract: Background

The detection characteristics of the spectral azimuthal γ-ray (SAGR) logging while drilling (LWD) tool are important for the early design of the instrument structure and subsequent interpretation of the logging data, so it is necessary to study its detection characteristics and its influencing factors.

Purpose

This study aims to investigate the effects of wellbore size, mud density, formation density, and natural radioactive material types on the SAGR instrument detection characteristics.

Methods

First of all, the instrument structure of the LWD spectral azimuthal gamma ray tool was determined, then the corresponding MCNP model was established. Based on the geometric factors in the induction logging, the radial, longitudinal and circumferential integral geometry factors of the SAGR instrument were simulated. Finally, the influence of wellbore size, mud density, formation density and different natural radioactive materials on the detection characteristics of the SAGR were studied by simulation.

Results

The results show that the wellbore size, formation density and natural radioactive material types have a great influence on the SAGR detection characteristics, while the mud density have no effect.

Conclusion

This study provides a theoretical reference for instrument design and logging data interpretation of the spectral azimuthal γ-ray logging while drilling tool.

Key words: LWD spectral azimuthal γ-ray, Geometric factors, Numerical simulation

CLC Number: 

  • TL99