Citation: | Changfu Yang, Changyou Lin. Identification and Correction for MT Static Shift Using TEM Inversion Technique. Journal of Earth Science, 2001, 12(3): 266-271. |
The inversion of TEM data, using the observed magnetic fields instead of that of apparent resistivities data in this paper, avoids the errors caused by the definition of the apparent resistivity. The inversed results by fitting the magnetic fields of the transmitter source's image with the observed magnetic fields are relatively less affected by the conductivity inhomogeneity. The MT apparent curve is calculated on the basis of the conductivity model constructed from the TEM inversion results. This curve is used as a reference curve for the correction of MT static shift, which makes the correction more reliable. Meanwhile, the domain transformation is also achieved from time to frequency between the two kinds of electromagnetic data. Therefore, the correction of the MT static shift is actualized using TEM inversion method. The corresponding application research shows that this method is very effective for the identification and correction of the MT static shift.
Beamish B, Travassos J M, 1992. A Study of Static Shift Removal from Magnetotelluric Data. J Appl Geophys, 29: 157-178 doi: 10.1016/0926-9851(92)90006-7 |
de Groot-Hedlin G, 1991. Removal of Static Shift in Two Dimensions by Regularized Inversion. Geophysics, 56: 2102-2106 doi: 10.1190/1.1443022 |
de Groot-Hedlin G, 1995. Inversion for Regional 2-D Resistivity Structure in the Presence of Galvanic Scatters. Geophys J Int, 122: 877-888 doi: 10.1111/j.1365-246X.1995.tb06843.x |
Eaton P A, Hohmann G W, 1989. A Rapid Inversion Technique for T ransient Electromagnetic Soundings. Phys Earth Planet Int, 53: 384-404 doi: 10.1016/0031-9201(89)90025-3 |
Jones A G, 1988. Static Shift of Magnetotelluric Data and Its Removal in a Sedimentary Basin Environment. Geophysics, 53: 967-978 doi: 10.1190/1.1442533 |
Lin C, Yang S, Ye J, 1994. One-Dimensional Inversion of TEM Late Time Field Data. Northwestern Seismological Journal, 16(2): 71 -78(in Chinese) |
Meju M A, 1996. Joint Inversion of TEM and Distorted MT Soundings: Some Effective Practical Considerations. Geophysics, 61: 56-65 doi: 10.1190/1.1443956 |
Nabighian M N, 1979. Quas-i Static T ransient Response of a Conducting Half Space-An Approximate Respresentation. Geophysics, 44: 1700-1705 doi: 10.1190/1.1440931 |
Nekut A G, 1987. Direct Inversion of Time-Domain Electromagnetic Data. Geophysics, 52: 1431-1435 doi: 10.1190/1.1442256 |
Ogawa T, Uchida T A, 1996. Two-Dimensional Magnetotelluric Inversion Assuming Gaussian Static Shift. Geophys J Int, 126: 69-76 doi: 10.1111/j.1365-246X.1996.tb05267.x |
Pellerin L, Hohmann G W, 1990. T ransient Electromagnetic Inversion: A Remedy for Magnetotelluric Static Shifts. Geophysics, 55: 1242-1250 doi: 10.1190/1.1442940 |
Raiche A P, Gallagher R G, 1985. Apparent Resistivity and Diffusion Velocity. Geophysics, 50: 1628-1633 doi: 10.1190/1.1441852 |
Spies B R, 1989. Depth of Investigation in Electromagnetic Methods. Geophysics, 54: 872-888 doi: 10.1190/1.1442716 |
Sternberg B K, 1988. Correction for the Static Shift in Magneto-Tellurics Using T ransient Electromagnetic Soundings. Geophysics, 53: 1459-1468 doi: 10.1190/1.1442426 |
Torresverdin C, Bostic Jr F X, 1992. Principles of Spatial Surface Electric Field Filting in Magnetotelluric: Electromagnetic Array Profiling (EMAP). Geophysics, 97: 603-622 |
Wannamaker P E, 1984a. Electromagnetic Modeling of T hree-Dimensional Bodies Using Integral Equations. Geophysics, 49: 60-74 doi: 10.1190/1.1441562 |
Wannamaker P E, 1984b. Magnetotelluric Responses of T hree-Dimensional Bodies in Layered Earths. Geophysics, 49: 1517-1533 doi: 10.1190/1.1441777 |
Wannamaker P E, 1986. Two-Dimensional Topographic Responses in Magnetotellurics Modeled Using Finite Elements. Geophysics, 51: 2131-2144 doi: 10.1190/1.1442065 |
Yang C, Lin C, 2000. Approximate Inversion for3-D TEM Data. Acta Seismologica Sinica, 22(4): 377-384(in Chinese) |