Sensitivity function technique for modeling nuclear tools

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364422, G01V 512

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053348338

ABSTRACT:
A new technique, called the sensitivity function technique, has been developed for modeling nuclear density tools. Specifically, sensitivity functions relate a change in formation properties to a change in detector response and are based on the first order perturbation expansion of the radiation transport equation. The sensitivity function is a quasi-linear model which works extremely well over a wide range of mudcake and formation conditions, as shown by extensive benchmark comparisons against actual tool measurements. The detector responses are calculated by a convolution of density sensitivity functions, calculated in a separate set of Monte Carlo computer runs, with the formation properties and is extremely fast. Because this technique is both fast and accurate, it represents a significant advance in the ability to model gamma-gamma density tools and will allow the use of fast forward modeling to improve the log interpretation process.

REFERENCES:
patent: 3321625 (1967-05-01), Wahl
patent: 3864569 (1975-02-01), Tittman
patent: 4048495 (1977-09-01), Ellis
patent: 4314339 (1982-02-01), Kenyon
patent: 4958073 (1990-09-01), Becker et al.
"Monte Carlo Computation of Differential Sensitivity Function", Watson, Transactions of the American Nuclear Society, vol. 46, Jun. 3-7, 1984, pp. 655-657.
"Deconvolution of Petrophysical Logs: Applications and Limitations," W. J. Looyestijn, SPWLA Twenty-Third Annual Logging Symposium, Jul. 6-9, 1982.
"Quantitative Uranium Determinations from Gamma-Ray Logs by Application of Digital Time Series Analysis," J. G. Conaway and P. G. Killeen, Geophysics, vol. 43, No. 6, Oct., 1978, pp. 1204-1221.
"Analysis of Deconvolution Efficiency for Some Well Logs," T. Zorski, SPWLA Twenty-Eighth Annual Logging Symposium, Jun. 29-Jul. 2, 1987.
"Enhanced Vertical Resolution Processing of Dual-Spaced Neutron and Density Tools Using Standard Shop Calibration and Borehole Compensation Procedures," M. P. Smith, SPWLA 31st Annual Logging Symposium, Jun. 24-27, 1990.
"An Algorithm for Simultaneous Deconvolution, Squaring and Depth-Matching of Logging Data," M. R. Spalburg, SPWLA Thirtieth Annual Logging Symposium, Jun. 11-14, 1989.
"Thin Bed Resolution Enhancement: Potential and Pitfalls," D. C. Minette, SPWLA 31st Annual Logging Symposium, Jun. 24-27, 1990.
"Simulation of Geological Profiled and Gamma Ray Logs," J. A. Czubek, Nucl. Geophys. vol. 1, No. 1, pp. 83-109, 1987.
"A Method of Geometrical Factors in the Theory and Interpretation of Formation Density Logging," D. A. Kozhevnikov and I. P. Khathmullin Nucl. Geophys. vol. 4, No. 4, pp. 413-424, 1990.
"Vertical Enhancement by Combination and Transformation of Associated Responses," P. A. S. Elkington et al., SPWLA 31st Annual Logging Symposium, Jun. 24-27, 1990.
"Characterization of Vertical Resolution for Pe and Density Logging," G. L. Mathis and D. Gearhart, SPWLA Twenty-Ninth Annual Logging Symposium, Jun. 5-8, 1988.
"Resolution Enhancement of Nuclear Measurements Through Deconvolution," L. A. Jacobson et al., Log Analyst, Nov.-Dec., 1991, pp. 663-669.
"Dual Spacing Formation Density Log", Wahl et al., Journal of Petroleum Technology, Dec. 1964, pp. 1411-1416.
"Eliminating the Effect of Rugosity from Compensated Density Logs by Geometrical Response Matching", Flaum et al., SPE 19612, pp. 419-427.
"Application of Sensitivity and Uncertainty Methodology to Fast Reactor Integral Experiment Analysis," Weisbin et al., Nucl. Sci. Eng., 66, 307, 1978.
"Cross Section Sensitivity and Uncertainty Analysis with Application to a Fusion Reactor," Gerstl et al., Nuc. Sci. Eng., 62, 137, 1977.
"The Physical Foundations of Formation Lithology Logging with Gamma Rays", Bertozzi et al., Geophysics, 46, No. 10, Oct. 1981.
"A Code Generated Monte Carlo Importance Function," Hendricks, J. S., Trans. Am. Nuc. Soc., 41, 307, 1982.

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