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A study on slim-hole neutron logging based on numerical simulation

소구경 시추공에서의 중성자검층 수치모델링 연구

  • Ku, Bonjin (Department of Energy and Mineral Resources Engineering, Sejong University) ;
  • Nam, Myung Jin (Department of Energy and Mineral Resources Engineering, Sejong University)
  • 구본진 (세종대학교 에너지자원공학과) ;
  • 남명진 (세종대학교 에너지자원공학과)
  • Received : 2012.11.16
  • Accepted : 2012.11.24
  • Published : 2012.11.30

Abstract

This study provides an analysis on results of neutron logging for various borehole environments through numerical simulation based on a Monte Carlo N-Particle (MCNP) code developed and maintained by Los Alamos National Laboratory. MCNP is suitable for the simulation of neutron logging since the algorithm can simulate transport of nuclear particles in three-dimensional geometry. Rather than simulating a specific tool of a particular service company between many commercial neutron tools, we have constructed a generic thermal neutron tool characterizing commercial tools. This study makes calibration chart of the neutron logging tool for materials (e.g., limestone, sandstone and dolomite) with various porosities. Further, we provides correction charts for the generic neutron logging tool to analyze responses of the tool under various borehole conditions by considering brine-filled borehole fluid and void water, and presence of borehole fluid.

Acknowledgement

Supported by : 한국에너지기술평가원(KETEP)

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