tailieunhanh - Resistivity inversion of transversely isotropic media

In this paper, we have suggested a finite difference algorithm for resistivity forward and inverse modeling with electrically anisotropic media in applied geophysics. Electrical anisotropy affects the surface measurement in a fashion that may make interpretation erroneous. | TÍÌBĨTAK Turkish Journal of Earth Sciences http earth Research Article Turkish J Earth Sci 2018 27 152-166 TUBITAK doi yer-1702-6 Resistivity inversion of transversely isotropic media Ertan PEK EN1 Tiirker YAS2 Department of Geophysical Engineering Faculty of Engineering Kocaeli University Kocaeli Turkey Department of Marine and Environmental Researches General Directorate of Mineral Research Exploration Ankara Turkey Received Accepted Published Online Final Version Abstract In this paper we have suggested a finite difference algorithm for resistivity forward and inverse modeling with electrically anisotropic media in applied geophysics. Electrical anisotropy affects the surface measurement in a fashion that may make interpretation erroneous. This means that the resistivity section obtained by an inversion method that does not incorporate electrical anisotropy gives the wrong subsurface structure. We used a classical multielectrode dataset of a profile for estimating not only horizontal but vertical resistivity as well. Thus the electrical anisotropy can be calculated. Finally the finite difference mesh can be corrected by using the estimated anisotropic coefficient. The result of the developed algorithm was verified with a 2-layered analytic solution. Furthermore the present method was also tested on a field dataset. Key words Electrical resistance tomography electrical anisotropy 2D resistivity modeling 2D resistivity inversion direct resistivity method transversely isotropic media 1. Introduction Electrical conductivity of a geological formation may vary in different directions depending on the formation s properties. This type of directional property of conductivity gives rise to electrical anisotropy Maillet 1947 . Ignoring the electrical anisotropy of a geological formation or assuming that the formation is isotropic may yield to a misleading interpretation Nguyen et al. 2007 Wiese et al. 2009 .