Abstract
The possibilities of estimating the macroanisotropic parameters of the earth by radiomagnetotelluric soundings with a controlled source in the form of a horizontal electric dipole (a cable with a finite length) are studied in the case of the measurements in the transition zone of the source, where the galvanic and induction modes of the excited electromagnetic field are both important. The forward problem for the considered high frequency band (up to 1000 kHz) is solved with allowance for the displacement currents in the ground and air. The algorithm of anisotropic 1D inversion of the sounding data is presented. The resolution parameters are estimated from the derivatives of the electromagnetic field components with respect to the model parameters. Based on the synthetic examples, it is shown that joint inversion of the impedance and tipper data in the transition zone of the source constrains the space of equivalent models and makes it possible to determine the macroanisotropy coefficient of the section.
Similar content being viewed by others
References
Abubakar, A., Li, M., Pan, G., Liu, J., and Habashy, T.M., Joint MT and CSEM data inversion using a multiplicative cost function approach, Geophysics, 2011, vol. 76, pp. F203–F214.
Barsukov, P.O., Fainberg, E.B., and Khabensky, E.O., Joint inversion of TEM and DC soundings, Abstr. 10th European Meeting of Environmental and Engineering Geophysics “Near surface” (Utrecht, 2004), Utrecht, 2004, pp. 1–4.
Bastani, M., EnviroMT-A New Controlled Source/Radio Magnetotelluric System, Uppsala: Acta Univ. Ups., 2001.
Berdichevsky, M.N. and Dmitriev, V.I., Modeli i metody magnitotelluriki (Models and Methods of Magnetotellurics), Moscow: Nauchnyi Mir, 2009.
Brown, V., Hoversten, M., Key, K., and Chen, J., Resolution of reservoir scale electrical anisotropy from marine CSEM data, Geophysics, 2012, vol. 77, no. 2, pp. E147–E158.
Bursian, V.R., Teoriya elektromagnitnykh polei, primenyaemykh v elektrorazvedke (Theory of Electromagnetic Fields Applied in Electrical Prospecting), Leningrad: Nedra, 1972.
Christensen, N.B., Difficulties in determining electrical anisotropy in subsurface investigations, Geophys. Prospect., 2000, vol. 48, no. 1, pp. 1–19.
Constable, S.C., Parker, R.L., and Constable, C.G., Occam’s inversion: a practical algorithm for generating smooth models from electromagnetic sounding data, Geophysics, 1987, vol. 52, no. 3, pp. 289–300.
Israil, M., Sudha, Tezkan, B., Gupta, Pravin K., and Rai, J., Joint inversion of TEM and DC resistivity data for mapping the groundwater contamination around Roorkee area, India, Abstr. 20th IAGA WG 1.2 Workshop on Electromagn. Induction in the Earth (Giza, 2010), Giza, 2010, pp. 1–4.
Ivanov, P.V., Alekseev, D.A., Bobachev, A.A., Pushkarev, P.Yu., and Yakovlev, A.G., On combining vertical electric soundings and near-zone transient electromagnetic methods, Inzh. Izyskaniya, 2011, no. 11, pp. 42–51.
Jupp, D.L.B. and Vozoff, K., Stable iterative method for the inversion of geophysical data, Geophys. J. R. Astron Soc., 1975, vol. 42, no. 3, pp. 957–976.
Jupp, D.L.B. and Vozoff, K., Resolving anisotropy in layered media by joint inversion, Geophys. Prospect., 1977, vol. 25, no. 3, pp. 460–470.
Kalscheuer, T., Pedersen, L. B., and Siripunvaraporn, W., Radiomagnetotelluric two-dimension forward and inverse modeling accounting for displacement currents, Geophys. J. Int., 2008, vol. 175, no. 2, pp. 486–514.
Keller, G.V. and Frischknecht, F.C., Electrical Methods in Geophysical Prospecting, Oxford: Pergamon, 1966.
Key, K., Is the fast Hankel transform faster than quadrature?, Geophysics, 2012, vol. 77, no. 3, pp. F21–F30.
Kraev, A.P., Osnovy geoelektriki (Basics of Geoelectrics), Leningrad: Gos. Izdat. Tekhn. Teoret. Literat., 1951.
Lu, X. and Xia, C., Understanding anisotropy in marine CSEM data, 77th SEG Int. Exposition and Annual Meeting (San Antonio, 2007), San Antonio: SEG, 2007, pp. 1131–1136.
Maier, D., Maurer, H.R., and Green, A.G., Joint inversion of related data sets: DC resistivity and transient electromagnetic soundings, Proc. 1st Ann. Symp. Environ. Engin. Geophys. Soc. (Torino, 1995), Torino: EEGS, 1995, pp. 461–464.
Maillet, R., The fundamental equations of electrical prospecting, Geophysics, 1947, no. 12, pp. 529–556.
Marquardt, D.W., An algorithm for least-squares estimation of non-linear parameters, J. Soc. Ind. Appl. Math., 1963, vol. 11, no. 2, pp. 431–441.
Masnaghetti, L. and Ceci, F., Analysis of the sensitivity to anisotropy of CSEM data using 2.5D modeling and inversion, 80th Annual Meeting: SEG Technical Program Expanded Abstracts (Tulsa, 2010), Tulsa: SEG, 2010, pp. 614–618.
Meju, M., Joint inversion of TEM and distorted MT soundings: some effective practical considerations, Geophysics, 1996, vol. 61, no. 1, pp. 56–65.
Newman, G.A., Commer, M., and Carazzone, J.J., Imaging CSEM data in the presence of electrical anisotropy, Geophysics, 2010, vol. 75, no. 2, pp. F51–F61.
Ogilvi, A.A., Osnovy inzhenernoi geofiziki. Uchebnik dlya vuzov (Introduction to Engineering Geophysics. University Textbook), Moscow: Nedra, 1990.
Raiche, A.P., Jupp, D.L.B., Rutter, H., and Vozoff, K., The joint use of coincident loop transient electromagnetic and Schlumberger sounding to resolve layered structures, Geophysics, 1985, vol. 50, no. 10, pp. 1618–1627.
Ramananjaona, C., MacGregor, L., and Andréis, D., Sensitivity and inversion of marine electromagnetic data in a vertically anisotropic stratified earth, Geophys. Prospect., 2011, vol. 59, no. 2, pp. 341–360.
Ray, A. and Key, K., Bayesian inversion of marine CSEM data with a trans-dimensional self parameterizing algorithm, Geophys. J. Int., 2012, vol. 191, pp. 1135–1151.
Regis, C.R.T., Luz, E.C., Santos, W.G., A method to improve the inversion of marine CSEM data from anisotropic layers, 75th EAGE Conf. and Exhibition Incorporating SPE EUROPEC 2013 (London, 2013), Red Hook, NY: Curran Associates, 2014, pp. 4377–4381.
Ryzhov, A.A., The algorithm for calculation of electromagnetic fields in the polarizable horizontally layered media, Izv. Akad. Nauk SSSR, Fiz. Zemli, 1989, no. 2, pp. 77–89.
Sørensen, K.I., The Ellog auger drilling method, Proc. 23rd Symp. on Application of Geophysics to Engineering and Environmental Problems (Boston, 1994), Boston: EEGS, pp. 985–994.
Saraev, A.K., Simakov, A.E., and Tezkan, B., Foot, mobile and controlled source modifications of the radiomagnetotelluric method, Near Surface Geoscience 2011. 17th European Meeting of Environmental and Engineering Geophysics (Leicester, 2011), Red Hook, NY: Curran Associates, 2011, pp. 571–575.
Saraev, A.K., Simakov, A.E., and Shlykov, A.A., Controlled-source radio magnetotelluric sounding method, Geofizika, 2014, no. 1, pp. 18–25.
Schlumberger, C., Schlumberger, M., and Leonardon, E.G., Some observations concerning electrical measurements, Trans. Am. Inst. Min., Metall. Pet. Eng., 1933, vol. 110, pp. 150–182.
Semenov, A.S., Fokin, A.F., and Veshev, A.V., The field of a point source in anisotropic half-space, Vopr. Geofiz. Uch. Zap. Leningr. Gos. Univ. im. A. A. Zhdanova, Ser. Fiz. Geol. Nauk, 1958, vo. 249, pp. 90–113.
Sheinmann, S.M., Elements of electric prospecting theory for anisotropic medium, Materialy VSEGEI, Geofiz., vol. 9–10, Moscow-Leningrad: Gosgeolizdat, 1941, pp. 105–144.
Shlykov, A.A. and Saraev, ?A.K., Wave effects in the field of a high-frequency horizontal electric dipole, Izv., Phys. Solid Earth, 2014, vol. 50, no. 2, pp.-249–262.
Simakov, A., Saraev, A., Antonov, N., Shlykov, A., and Tezkan, B., Mobile and controlled source modifications of the radiomagnetotelluric method and prospects of their application in the near-surface geophysics, Abstr. 20th IAGA WG 1.2 Workshop on Electromagn. Induction in the Earth (Giza, 2010), Giza, 2010, S5–P9.
Siripunvaraporn, W. and Egbert, G., An efficient data-subspace inversion method for 2D magnetotelluric data, Geophysics, 2000, vol. 65, no. 3, pp. 791–803.
Stoyer, C., Equivalence analysis of DC and EM data for layered models using the resolution matrix, Proc. 23 rd Symp. on Application of Geophysics to Engineering and Environmental Problems 2010 (Keystone, 2010), Red Hook: Curran Associates, 2010, pp. 173–182.
Tompkins, M. and MacGregor, R.W.L., Effects of vertical anisotropy on marine active source electromagnetic data and inversions, Extended Abstracts and Exhibitors’ Catalogue 66th EAGE Conf. and Exhibition (Paris, 2004), Houten: EAGE, 2004, pp. 4377–4381.
Vanyan, L.L., Osnovy elektromagnitnykh zondirovanii (Basics of Electromagnetic Sounding), Moscow: Nedra, 1965.
Vanyan, L.L., Elektromagnitnye zondirovaniya (Electromagnetic Sounding), Moscow: Nauchnyi Mir, 1997.
Zonge, K.L. and Hughes, L.J., Controlled source audiofrequency magnetotellurics, in Electromagnetic Methods in Applied Geophysics, Part B., Vol. 2, Nabigyan, M.N., Ed., Tulsa: SEG, 1991, pp. 713–809.
Author information
Authors and Affiliations
Corresponding author
Additional information
Original Russian Text © A.A. Shlykov, A.K. Saraev, 2015, published in Fizika Zemli, 2015, No. 4, pp. 128–147.
Rights and permissions
About this article
Cite this article
Shlykov, A.A., Saraev, A.K. Estimating the macroanisotropy of a horizontally layered section from controlled-source radiomagnetotelluric soundings. Izv., Phys. Solid Earth 51, 583–601 (2015). https://doi.org/10.1134/S1069351315040102
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S1069351315040102