Abstract
This paper reviews the magnetotelluric (MT) method with emphasis on recent improvements and the emerging applications. Recent improvements are in recognition of statics effects and their treatment, and in analysis of impedance tensors in 3D structural conditions. In spite of substantial progress in the analysis of the tensor, there are still unresolved questions regarding its information content, in terms of degrees of freedom.
There has also been slow but steady progress in inversion, with the development of methods of downward continuation in 1D, 2D and 3D, in time, depth and frequency domains. An improved understanding of the limitations of MT is leading to more joint use with other methods.
At shallow depths MT has become an accepted weapon in the arsenal used to explore for petroleum, geothermal resources and epithermal gold and deep base metals. Improved understanding of the relations between conductivity and rock composition and fabric will make MT more useful for engineering purposes in future. Progress in understanding the cause of conduction in the deep crust and upper mantle has been less rapid, and the many anomalies remain enigmatic.
Whereas MT is now a useful technique with some unique applications, there are obviously important and difficult problems remaining to be solved.
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References
Abramovici F 1974 The forward magnetotelluric problem for an inhomogeneous and anisotropic structure;Geophysics 39 56–68
Andrieux P and Wightman W E 1984 The so-called static corrections in magnetotelluric measurements; Expanded Abstract EM 1.1, 54th Annual SEG Meeting.
Ballestracci R 1982 Audiomagnetotelluric profiling on the Volcano Stromboli, internal structure and mechanism of the Strombolian activity;J. Volc. Geoth. Res. 12 317–337
Bear J 1972Dynamics of fluids in porous media (New York: American Elsevier)
Bendat J S and Piersol A G 1971Random data: analysis and measurement procedures: (New York: John Wiley)
Benderitter Y and Gerard A 1984 Geothermal study of Reunion Island: Audiomagnetotelluric survey;J. Volc. Geoth. Res. 20 311–332
Berdichevsky M N and Dmitriev V I 1976 Basic principles of interpretation of magnetotelluric curves. InGeoelectric and geothermal studies: (ed.) A Adam (Budapest: Akademiai Kiado) pp. 165–124
Berkman E, Orange A and Smith R D 1983 Seismic and magnetotellurics combined: A case history of the South Clay Basin Prospect; Expanded Abstract ELEC4, 53rd Annual SEG Meeting
Boehl J E, Bostick F X and Smith H W 1977 An application of the Hilbert transform to the magnetotelluric method;Tech. Rep., Elec. Eng. Res. Lab., University of Texas
Bostick F X Jr 1977 A simple almost exact method of MT analysis: Abstract: in Workshop on electrical methods in geothermal exploration, Snowbird, Utah
Bostick F X Jr 1986 Electromagnetic array profiling (EMAP): Expanded abstract EM 2.1, 56th Annual SEG Meeting, Houston, Tex., 60–61
Brewitt-Taylor C R and Weaver J T 1976 On the finite difference solution of two-dimensional induction problems;Geophys. J. R. Astron. Soc. 47 375–396
Cagniard L 1953 Basic theory of the magnetotelluric method of geophysical prospecting;Geophysics 18 605–635
Cantwell T 1960Detection and analysis of low frequency magnetotelluric signals; Ph.D. thesis, Mass. Inst. Tech., Cambridge, Mass
Cerv V and Pek J 1981 Numerical solution of the two-dimensional inverse geomagnetic induction problem;Stud. Geophys. Geod. 25 69–80
Cevallos C 1986Magnetotelluric interpretation-another approach, Ph.D. thesis, Macquarie University, Sydney, Australia
Chave A D, Thomson D J and Ander M E 1987 On the robust estimation of power spectra, coherences and transfer functions;J. Geophys. Res. 92 633–648
Clay C S and Hinich M J 1981 Estimating the earth’s impedance function when there is noise in the electric and magnetic signals. In:Applied time series II (Academic Press) pp. 189–219
Coen S, Quercia F and Mackiewicz M 1983 Direct inversion of one-dimensional magnetotelluric data;J. Geophys. Res. B88 2407–2412
Constable S C, Parker R L and Constable C G 1987 Occam’s inversion: A practical algorithm for generating smooth models from electromagnetic sounding data;Geophysics 52 289–300
D’Erceville L and Kunetz G 1962 The effect of a fault on the earth’s natural electromagnetic field;Geophysics 27 666–676
Eadie T 1981 Detection of hydrocarbon accumulations by surface electrical methods: A feasibility study;Research in applied geophysics, No. 15, M.Sc. Thesis, University of Toronto
Egbert G D and Booker J R 1986 Robust estimation of geomagnetic transfer functions;Geophys. J. R. Astron. Soc. 87 173–194
Eggers D E 1982 An eigenstate formulation of the magnetotelluric impedance tensor;Geophysics 47 1204–1214
Filloux J H, Lilley F E M, Ferguson I J, Bindoff N L and Mulhearn P J 1985 The Tasman project of seafloor magnetotelluric exploration (Ex-tended abstract);Explor. Geophys. 16 221–223
Filloux J H 1987Instrumentation and experimental methods for oceanic studies in Geomagnetism (ed.) J A Jacobs (London: Academic Press) pp. 143–248
Fischer G and Schnegg P A 1980 The dispersion relations of the magnetotelluric response and their incidence on the inversion problem;Geophys. J. R. Astron. Soc. 62 661–673
Flores-Luna C F 1986Electromagnetic induction studies over the Meager Creek Geothermal Area, British Columbia; Ph.D. thesis, University of Toronto, Canada
Gamble T D, Goubau WM and Clarke J 1979 aMagnetotellurics with a remote reference;Geophysics 44 53–68
Gamble T D, Goubau W M and Clarke J 1979 bError analysis for remote reference magnetotellurics;Geophysics 44 959–968
Goubau W M, Maxton P M, Koch R H and Clarke J 1984 Noise correlation lengths in remote reference magnetotellurics;Geophysics 49 433–438
Groom R W and Bailey R C 1988 A decomposition of the magnetotelluric impedance tensor which is useful in the presence of channeling;J. Geophys. Res. (submitted)
Gunderson B M, Newman G A and Hohmann G W 1986 Three-dimensional transient electromagnetic responses for a grounded source;Geophysics 51 2117–2130
Handbook of chemistry and physics, 1985 (ed.) R C Weast, Boca (Raton, Fla: CRC Press)
Hastings R 1986 Superconducting magnetic gradiometer for geophysical application. In:Symposium on gravity and magnetic gradiometry La Habra, Calif, Feb. 1986
Hoehn G L and Warner B N 1983 Magnetotelluric measurements in the Gulf of Mexico at 20 m depth. In:CRC handbook of geophysical exploration at sea, (ed.) R Geyer (Boca Raton: CRC Press)
Hohmann G W 1988 Numerical modeling for electromagnetic methods of geophysics. In:Electromagnetic methods in applied geophysics-Theory 1 (ed.) M Nabighian (Soc. Explor. Geophys.) 313–363
Hoover D B, Frischknecht F C and Tippens C L 1976 Audiomagnetotelluric sounding as a reconnaissance exploration technique in Long Valley, California;J. Geophys. Res. 81 801–809
Hopkins G H 1966An investigation of the magnetotelluric method for determining subsurface resistivities Ph.D. Thesis, University of Texas, Austin
Jiracek G R, Gustafson E P and Mitchell P S 1983 Magnetotelluric results opposing magma origin of crustal conductors in the Rio Grande Rift;Tectonophysics 94 299–326
Jiracek G R, Rodi W L and Vanyan L L 1987 Implications of magnetotelluric modelling for the deep crustal environment in the Rio Grande Rift;Phys. Earth Planet. Inter. 45 179–192
Jones A G 1983 On the equivalence of the Niblett and Bostick transformations in the magnetotelluric method;J. Geophys. 53 72–73
Jones F W and Price A T 1971 aThe perturbations of alternating geomagnetic fields by conductivity anomalies;Geophys. J. R. Astron. Soc. 20 317–334
Jones F W and Price A T 1971b Geomagnetic effects of sloping and shelving discontinuities of earth conductivity;Geophysics 36 58–66
Jones F W and Vozoff K 1978 The calculation of magnetotelluric quantities for three-dimensional conductivity inhomogenietiesGeophysics 43 1167–1175
Jupp D L B and Vozoff K 1975 Stable iterative methods for the inversion of geophysical data;Geophys. J. R. Astron. Soc. 42 957–976
Jupp D L B and Vozoff K 1976 Discussion on the magnetotelluric method in the exploration of sedimentary basins;Geophysics 41 325–328
Jupp D L B and Vozoff K 1977 Resolving anisotropy in layered media by joint inversion;Geophys. Prosp. 25 460–470
Kato Y and Kikuchi T 1950 On the phase difference of earth current induced by changes of the earth’s magnetic field;Sci. Rep. Tohoku Univ. Ser. V, Geophysics 2 pts 1 & 2 139–145
Katz A J and Thompson A H 1987 Prediction of rock electrical conductivity from mercury injection measurements;J. Geophys. Res. 92B1 599–607
Keller G V 1988 Rock and mineral properties. In: Electromagnetic methods in applied geophysics-Theory I, (ed.) M NabighianSoc. Explor. Geophys. pp. 13–51
Kunetz G 1972 Processing and interpretation of magnetotelluric soundings;Geophysics 37 1005–1021
Larsen J C 1981 A new technique for layered earth magnetotelluric inversion;Geophysics 46 1247–1257
Lakanen E 1986 Scalar audiomagnetotellurics applied to base-metal exploration in Finland;Geophysics 51 1628–1646
LaTorraca G A, Madden T R and Korringa J 1986 An analysis of the magnetotelluric impedance for three-dimensional conductivity structures;Geophysics 51 1819–1829
Lee S, McMechan G A and Aiken C L V 1987 Phase-field imaging: The electromagnetic equivalent of seismic migration;Geophysics 52 678–693
Lee C D, Vine F J and Ross R G 1983 Electrical conductivity models for the continental crust based on laboratory measurements on high grade metamorphic rocks;Geophys. J. R. Astron. Soc. 72 353–371
Levy S, Oldenburg D and Wang J 1988 Subsurface imaging using magnetotelluric data;Geophysics 53 104–117
Liu Xiaoshan, Fan Sheng, Yang Ling and Wang Jiaying 1987 A new magnetotelluric inversion method-Vertical time-distance curve method: Oil Geophysical Prospecting22 445–453 (Chinese with English abstract).
Lüschen E, Wenzel F, Sandmeier K J, Menges D, Rühl T, Stiller M, Janoth W, Keller F, Söllner W, Thomas R, Krohe A, Stenger R, Fuchs K, Wilhelm H and Eisbacher G1987 Near-vertical and wide-angle seismic surveys in the Black Forest, SW Germany;J. Geophys. 62 1–30
Mabeyn D R, Hoover D B, O’Donnell J E and Wilson C W 1978 Reconnaissance geophysical studies of the geothermal system in the southern Raft River Valley, Idaho;Geophysics 43 1470–1484
Maclnnes S and Wait J R 1988 Lateral effects in controlled source audio frequency MT: URSI Radio Science Meeting (Abstract), Syracuse, N.Y.
Madden T R 1971 EMCDC: Two-dimensional network modeling program: (unpublished)
Madden T R 1976 Random networks and mixing laws;Geophysics 41 1104–1125
Madden T R and Nelson P 1986 A defense of Cagniard’s magnetotelluric method. In:Magnetotelluric methods, (ed.) K Vozoff, Geophysics Reprint Series No. 5, Soc. Explor. Geophys. pp. 89–102
Maidens J M and Paulson K V 1988 A magnetotelluric investigation under the Williston Basin of south-eastern Saskatchewan;Can. J. Earth Sci. 25 60–67
Menke W 1984Geophysical data analysis: Discrete inverse theory (Florida: Academic Press)
Nabighian M (ed.) 1988Electromagnetic methods in applied geophysics — Theory I (Soc. Explor. Geophys.)
Nabighian M (ed.) 1989Electromagnetic methods in applied geophysics II, (Soc. Explor. Geophys.)
Niblett E R and Sayn-Wittgenstein C 1960 Variation of electrical conductivity with depth by the magnetotelluric method;Geophysics 25 998–1008
Oldenburg D W 1979 One-dimensional inversion of natural source magnetotelluric observations;Geophysics 44 1218–1244
Oldenburg D W 1984 An introduction to linear inverse theory;Inst. Elect. and Electron. Eng. Trans. Geosci. Remote Sens. GE-22 665–674
Olhoeft G R 1983 Low-frequency electrical properties;Geophysics 50 2492–2503
Orr D 1984 Magnetospheric hydromagnetic waves: their eigenperiods, amplitudes and phase variations; a tutorial introduction;J. Geophys. 55 76–84
Papoulis A 1962The Fourier integral and its applications (New York: McGraw-Hill)
Park S K, Orange A S and Madden T R 1983 Effects of three-dimensional structure on magnetotelluric sounding curves;Geophysics 48 1402–1405
Park S K 1985 Distortion of magnetotelluric sounding curves by three-dimensional structures;Geophysics 50 785–797
Parker R L 1983 The magnetotelluric inverse problem;Geophys. Surv. 6 5–25
Petiau G and Dupis A 1980 Noise, temperature coefficient and long time stability of electrodes for telluric observations;Geophys. Prosp. 28 792–804
Pek J 1987 Numerical inversion of 2D MT data by models with variable geometry;Phys. Earth Planet. Inter. 45 193–203
Pierce E T 1977 Atmospherics and radio noise, inLightning (ed.) R H Golde (Academic Press) vol1 pp. 351–384
Prieto C, Perkins C and Berkman E 1984 Columbia River basalt plateau: An integrated approach to interpretation of basalt-covered areas; Extended Abstract EM 4.7, 54th Annual SEG Meeting
Raiche A P, Jupp D L B, Rutter H and Vozoff K 1985 The joint use of coincident loop transient electromagnetic and Schlumberger sounding to resolve layered structures;Geophysics 50 1618–1627
Ranganayaki R P 1984 An interpretive analysis of magnetotelluric data;Geophysics 49 1730–1748
Rankin D 1962 The magnetotelluric effect on a dike;Geophysics 27 651–665
Rasmussen T M, Roberts R G and Pedersen L B 1987 Magnetotellurics along the Fennoscandian Long Range profile;Geophys. J. R. Astron. Soc. 89 799–820
Rikitake T 1950 Electromagnetic induction within the earth and its relation to the electrical state of the earth’s interior;Bull. Earthq. Res. Inst. Tokyo 28 45
Ritz M and Vassal J 1986 The geoelectrical structure of the northern part of the Senegal Basin from joint interpretation of magnetotelluric and geomagnetic data;J. Geophys. Res. 91B10 10443–10456
Rodi W L, Swanger H J and Minister J B 1983 ESP:MT: An interactive system for two-dimensional magnetotelluric inversion; Extended abstract MT3, 53rd Annual SEG Meeting
Rokityansky II1961 On the application of the magnetotelluric method to anisotropic and inhomogeneous masses;Izvestia 11 1607–1613
Rostoker G 1979 Geomagnetic micropulsations;Fund. Cosmic Phys. 4 211–311
Schlumberger 1978Log interpretation principles/applications (Houston: Schlumberger Educational Services)
Shankland T J and Ander M E 1983 Electrical conductivity, temperatures, and fluids in the lower crust;J. Geophys. Res. 88B11 9475–9484
Shawan S D 1979 Magnetospheric plasma waves. In:Solar system plasma physics (eds.) L J Lanzerotti, C F Kennel and E N Parker (Amsterdam: North Holland) vol. 3 211–270
Spies B R and Eggers D E 1986 The use and misuse of apparent resistivity in electromagnetic methods;Geophysics 51 1462–1471
Stanley W D 1982 Magnetotelluric soundings on the Idaho National Engineering Laboratory Facility, Idaho;J. Geophys. Res. B87 2683–2691
Stanley W D, Saad A R and Ohofugi W 1985 Regional magnetotelluric surveys in hydrocarbon exploration, Parana Basin, Brazil;Am. Assoc. Petr. Geol. Bull. 69 346–360
Sternberg B K, Buller P L, Kisabeth J L and Mehreteab E 1982 Electrical methods for hydrocarbon exploration: II Magnetotelluric (MT) method. In:Proc. Symp. on Unconventional Methods in Exploration for Petroleum and Natural Gas, Dallas (S M U Press)
Sternberg B K, Washburne J C and Anderson R G 1985 Investigation of MT static shift correction methods; Extended abstract, 55th Annual SEG Meeting pp. 264–267
Strangway D W, Redman J D and Macklin D 1980 Shallow electrical sounding in the Precambrian crust of Canada and the United States; In:The continental crust and its mineral deposits, (ed.) D W Strangway (Geol. Assoc. Canada) Spec. Paper 20, pp. 273–301
Stratton JA 1941Electromagnetic theory (New York: McGraw-Hill)
Swift C M Jr 1971 Theoretical magnetotelluric and Turam response from two-dimensional inhomogeneities;Geophysics 36 38–52
Telford W M, Geldart L P, Sheriff R E and Keys D A1976Applied geophysics (Cambridge: University Press.)
Tikhonov A N 1950 On determining electrical characteristics of the deep layers of the earth’s;Doklady 73 295–297 (English translation in Vozoff 1986)
Ting S C and Hohmann G W 1981 Integral equation modeling of three-dimensional magnetotelluric response;Geophysics 46 182–197
Tozer D C 1959 The electrical properties of the earth’s interior;Phys. Chem. Earth 3 414–436
Travis B J and Chave A D 1986 A moving finite element model for 2D magnetotelluric analysis; Eighth Workshop on Electromagnetic Induction in the Earth and Moon, Abstract T7
Tyburczy J A and Waff HS 1983 Electrical conductivity of molten basalt and andesite to 25 kilobars pressure: geophysical significance and implications for charge transport and melt structure;J. Geophys. Res. 88B3 2413–2430
Van Blaricom R (ed.) 1980Practical geophysics for the exploration geologist (Spokane Wash: Northwest Mining Assoc.)
Volland H 1982 Low frequency radio noise. In (ed.) H Volland;Handbook of atmospherics CRC Press, vol. 1 179–250
Vozof TK 1972 The magnetotelluric method in the exploration of sedimentary basins;Geophysics 37 98–141 (also see Jupp and Vozoff 1976 for errata.)
Vozoff K (ed.) 1986Magnetotelluric methods; Soc. Explor. Geophys. Geop. Reprint Ser. No. 5
Vozoff K 1991 The magnetotelluric method. In:Electromagnetic methods in applied geophysics II (ed.) M Nabighian (Soc. Explor. Geophys.)
Vozoff K and Jupp D L B 1975 Joint inversion of geophysical data;Geophys. J. R Astron. Soc. 42 977–991
Vozoff K, LeBrocq L, Moss D, Zile M and Pridmore D 1985 Deep transient electromagnetic soundings for petroleum exploration: Final report, NERDDC Proj. 683, Macquarie University Sydney
Wait J R 1962 Theory of magnetotelluric fields;J. Res. N. B. S. D66 509–541
Wang Jia-ying, Oldenburg D and Levy S 1985 Seismic interpretation of magnetotelluric sounding data;Petroleum Geophys. Explor. 20 65–79 (Chinese with English abstract)
Wang Jia-ying, Zuo Hai-yan, Fang Shang and Sun Jian-guo 1986 Pseudoseismic interpretation to MT: Abstract, ISPCA Conf., Nanjing
Wannamaker P E, Hohmann G W and SanFilipo W A 1984a Electromagnetic modeling of three-dimensional bodies in layered earths using integral equations;Geophysics 49 60–74
Wannamaker P E, Hohmann G W and Ward S H 1984 bMagnetotelluric responses of three-dimensional bodies in layered earths;Geophysics 49 1517–1533
Wannamaker P E, Stodt J A and Rijo L 1986 Two-dimensional topographic responses in magnetotellurics modelled using finite elements;Geophysics 51 2131–2144
Warner B N, Bloomquist M G and Griffith P G 1983 Magnetotelluric interpretations based upon new processing and display techniques; Expanded abstract MT4, 53rd Annual SEG Meeting, Las Vegas pp. 151–154
Weidelt P 1972 The inverse problem of geomagnetic induction;J. Geophys. 38 257–289
Weidelt P 1975 Inversion of two-dimensional conductivity structures;Phys. Earth Planet. Inter. 10 282–291
West G F and Edwards R N 1985 A simple parametric model for the electromagnetic response of an anomalous body in a host medium;Geophysics 50 2542–2557
Whittall K P and Oldenburg D W1986 Inversion of magnetotelluric data using a practical inverse scattering formulation;Geophysics 51 383–395
Wight D E and Bostick F X 1980 Cascade decimation-A technique for real time estimation of power spectra;Proc. IEEE ICASSP, 626–629: InMagnetotelluric methods (ed) K Vozoff (Soc. Explor. Geophys.)
Wight D E, Bostick F X and Smith H W 1977 Real time fourier transformation of magnetotelluric data; Tech. Report, EGRL/EERL, University of Texas, Austin
Wightman W E and Andrieux P 1984 Transient and magnetotelluric soundings: A combined interpretation over a volcanic covered area in Wyoming; Expanded Abstract EM 1.8, 54th Annual SEG Meeting
Yale D P 1985 Recent advances in rock physics;Geophysics 50 2480–2491
Yamashita M, Hallof P G and Pelton W H 1985 CSAMT case histories with a multichannel CSAMT system and near-field data correction; Expanded Abstract MT8, 55th Annual SEG Meeting
Yee E and Paulson K V 1987 The canonical decomposition and its relationship to other forms of magnetotelluric impedance tensor analysis;J. Geophys. 61 173–189
Young C T and Repasky T R 1986 A magnetotelluric transect of the Jacobsville Sandstone in northern Michigan;Geol. Soc. Am. Bull. 97 711–716
Young C T, Booker J R, Fernandez R, Jiracek G R, Martinez M, Rogers J C, Stodt J, Waff H S and Wannamaker P E 1988 Verification of five magnetotelluric systems in the mini-EMSLAB experiment;Geophysics 53 553–557
Young R A and Lucas J E 1988 Exploration beneath volcanics: Snake River Plain Idaho;Geophysics 53 444–452
Zhang P, Roberts R G and Pedersen L B 1987 Magnetotelluric strike rules;Geophysics 52 267–278
Zhdanov M S and Frenkel M A 1983 Electromagnetic migration. In:The development of the deep geoelectric model of the Baltic Shield pt. 2. University of Oulu Rep. No. 8
Zonge K L, Ostrander A G and Emer D F 1986 Controlled source audiofrequency magnetotelluric measurements. In:Magnetotelluric methods (ed.) K Vozoff Soc. Explor. Geophys. 749–763
Zonge K L and Hughes L J 1989 Controlled source audio-frequency magnetotellurics. In:Electromagnetic methods in applied geophysics II In press
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Vozoff, K. Magnetotellurics: Principles and practice. Proc. Indian Acad. Sci. (Earth Planet Sci.) 99, 441–471 (1990). https://doi.org/10.1007/BF02840313
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DOI: https://doi.org/10.1007/BF02840313