Modification of ΔlogR method and Nonlinear Regression Application for Total Organic Carbon Content Estimation from Well Logs

Abstract

ΔlogR method is one of the most widely utilized techniques for estimation of Total Organic Carbon (TOC) content form well logs. The traditional ΔlogR method reveals the assumption of linear relationship between logarithmic resistivity and porosity log. In this study, the method is modified by means of integral calculus to acquire the actual trend between logarithmic resistivity and porosity log. Furthermore, unlike to the traditional method, the maturity is additionally represented with logarithm of organic maturation temperature. Nonlinear regression is applied to optimize the unclear organized parameters required for computation of TOC content. The final forms of the equations are observed to be appropriate for the nonlinear regression application. The TOC estimations are observed to be improved with the modified versions in case traditional methods are unsatisfactory due to the related assumption expressed above. With the introduced methodology the TOC of unconventional reservoirs and source rocks can be more accurately calculated.

Keywords

• Total Organic Carbon
• Well Logs
• Nonlinear Regression
• Unconventional Resources

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