A Semi-Automatic 2-D Linear Inversion Algorithm Including Depth Weighting Function for DC Resistivity Data: A Case Study on Archeological Data Sets of Pompeii

Document Type : Research Article

Authors

1 Ph.D. Student, Department of Earth Physics, Institute of Geophysics, University of Tehran, Tehran, Iran

2 Associate Professor, Department of Earth Physics, Institute of Geophysics, University of Tehran, Tehran, Iran

Abstract

In this paper, a new simple, efficient and semi-automatic algorithm including depth weighting constraint is introduced for 2-D DC resistivity data inversion. Inversion procedure is linear; however, DC resistivity data inversion is generally nonlinear due to the nonlinearity of Maxwell’s equation relative to resistivity (conductivity). We took the advantage of the 2-D forward operator formula obtained based on integral equations (IE) by Perez- Flores et al. (2001), for the inversion algorithm. Inversion algorithm is iterative and regularization parameter and depth weighting exponent are the critical parameters that have default values of 0.1 and 1, respectively. The presented technique was used only for dipole-dipole array by Perez-Flores et al. (2001), but here in addition to improving results for dipole-dipole array, its productivity is demonstrated for other geo-electrical arrays such as Wenner alfa, Wenner Schlumberger. Three synthetic data sets computed by Res2dmod software are utilized to investigate the performance of the algorithm through comparing the results with Res2dinv software output sections. Finally, the algorithm is applied on an archeological data set of Pompeii, which was collected by dipole-dipole array. IE inversion algorithm lead to satisfactory inversion models for both synthetic and real cases which reconstruct the subsurface better than or as well as that of the software.

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References

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Journal of the Earth and Space Physics
Volume 46, Issue 4
February 2021
Pages 65-77

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