caa a22 4500 475813391 CHVBK 20180406123803.0 cr unu---uuuuu 170329e20001001xx s 000 0 eng 10.1007/PL00001058 doi (NATIONALLICENCE)springer-10.1007/PL00001058 Çağlar İ. Department of Geophysical Engineering, İstanbul Technical University, Faculty of Mines, 80626 Maslak, İstanbul, Turkey. E-mail: caglari@itu.edu.tr, TR aut A Method to Remove Electromagnetic Coupling from Induced Polarization Data for an "Exponential” Earth Model [Elektronische Daten] [İ. Çağlar] —The electromagnetic (EM) coupling effect in induced polarization (IP) data is an important problem. In many works it has been computed only considering homogeneous or layered earth models with discretely uniform conductivity. In this study, an algorithm has been developed to compute the EM coupling effect in IP data measured on the earth, whose conductivity varies (increases or decreases) exponentially with depth. The EM coupling effects for Percent Frequency Effect (PFE) and phase data are computed for a dipole-dipole array with different separations, however the method can be applied to any electrode array. The results obtained for the cases of increasing and decreasing conductivity as a function of depth indicate that the EM coupling effect strongly depends on the subsurface resistivity and the dipole length. Here an "exponential” earth model is considered to remove EM coupling from the IP data in frequency and phase domain. For this purpose, first, the region of pseudo-section is divided into segments, and within each segment a typical average apparent resistivity (ρ a) curve is constructed. An exponential conductivity model is fitted to average ρ a data. The conductivity model is then used to compute EM responses. Next the data are corrected for the EM coupling contribution. This decoupling process is applied to field data from a galenite-pyrite mineralization area at the Dolluk site, in western Turkey. The results from the decoupling method developed here are compared with other techniques. Birkhäuser Verlag Basel,, 2000 Key Words: Induced polarization, electromagnetic coupling, exponential variation of resistivity, mineral exploration, Turkey nationallicence https://doi.org/10.1007/PL00001058 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/PL00001058 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Çağlar İ. Department of Geophysical Engineering, İstanbul Technical University, Faculty of Mines, 80626 Maslak, İstanbul, Turkey. E-mail: caglari@itu.edu.tr, TR aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer