The Resistivity Logging Response through Casing of Eight-Layer Formations with Cement Sheath

Abstract:

Because difference of formation model affects the potential distribution on the metal casing, the resistivity logging response can be obtained through casing by measuring the potentials on the metal casing. In fact, the logging responses are the comprehension effects of complex formation with cement sheath and metal casing, so that in the coefficients of transmission line equation (TLE), we should consider the effects of formation with cement sheath model in radial-direction. In the following, for the formation with cement sheath taking on eight-layer in axial-direction, and step in radial-direction, the resistivity logging responses through casing are researched and discussed, and given the recurrence formula with cement sheath to compute potential. Draw the curve of the resistivity logging response through casing of eight-layer formations with cement sheath. The conductivity of formation is computed is very approximating to that of formation with cement sheath model. The computing examples also show that this method has a fast computing speed (the run time of computing example is less than 1s). For analysis the logging response of eight-layers and block formations with cement sheath, and the design of logging instruments, the research is important significance and useful.

• Periodical: Advanced Materials Research (Volumes 1004-1005)
• Pages: 1378-1381
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1004-1005.1378
• Online since: August 2014
• Authors: An Ling Wang, Fu Ping Liu
• Keywords: Formation with Cement Sheath Model, Integral Equation Approach, Logging Response, Resistivity Logging through Casing, Transmission Line Equation

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