Research ArticleOpen AccessGoogle Scholar indexed
The Modeling of 2D Controlled Source Audio Magnetotelluric (Csamt) Responses Using Finite Element Method
Physics of Earth and Complex System,Fac. of Math. and Nat. Sci., Institut Teknologi Bandung, Indonesia
Physics of Earth and Complex System,Fac. of Math. and Nat. Sci., Institut Teknologi Bandung, Indonesia
Physics of Earth and Complex System,Fac. of Math. and Nat. Sci., Institut Teknologi Bandung, Indonesia
Applied Geology, Fac. of Earth Science and Technology,Institut Teknologi Bandung, Indonesia
- 1 Physics of Earth and Complex System,Fac. of Math. and Nat. Sci., Institut Teknologi Bandung, Indonesia
- 2 Physics of Earth and Complex System,Fac. of Math. and Nat. Sci., Institut Teknologi Bandung, Indonesia
- 3 Physics of Earth and Complex System,Fac. of Math. and Nat. Sci., Institut Teknologi Bandung, Indonesia
- 4 Applied Geology, Fac. of Earth Science and Technology,Institut Teknologi Bandung, Indonesia
Journal of Electromagnetic Analysis and Applications·Volume 04 (2012)·Pages 293–304·Published 23 July 2012·DOI10.4236/jemaa.2012.47041
Copy link · social · email
Abstract
This paper presents the modeling of 2D CSAMT responses generated by horizontal electric dipole using the separation of primary and secondary field technique. The primary field is calculated using 1D analytical solution for homogeneous earth and it is used to calculate the secondary electric field in the inhomogeneous Helmholtz Equation. Calculation of Helmholtz Equation is carried out using the finite element method. Validation of this modeling is conducted by comparison of numerical results with 1D analytical response for the case of homogeneous and layered earth. The comparison of CSAMT responses are also provided for 2D cases of vertical contact and anomalous conductive body with the 2D magnetotelluric (MT) responses. The results of this study are expected to provide better interpretation of the 2D CSAMT data.
KeywordsEM ModelingCSAMTFinite Element Method
- M. A. Goldstein and D. W. Strangway, “Audio-Frequency Magnetotellurics with a Grounded Electric Dipole Source,” Geophysics, Vol. 40, No. 4, 1975, pp. 669-683.
- S. K. Sandberg and G. W. Hohmann, “Controlled Source Audio Magnetotelluricsin Geothermal Exploration,” Geophysics, Vol. 59, 1982, pp. 100-116.
- P. E. Wannamaker, “Tensor CSAMT Survey over the Sulphur Springs Thermal Area, Valles Caldera, New Mexica, USA, Part I: Implications for Structure of the Western Caldera,” Geophysics, Vol. 62, No. 2, 1997, pp. 451465.
- P. E. Wannamaker, “Tensor CSAMT Survey over the Sulphur Springs Thermal Area, Valles Caldera, New Mexica, USA, Part II: Implications for CSAMT Methodology,” Geophysics, Vol. 62, No. 2, 1997, pp. 466-476.
- L. J. Hughes and N. R. Carlson, “Structure Mapping at Trap Spring Oilfield, Nevada Using Controlled-Source Magnetotellurics,” First Break, Vol. 5, No. 11, 1987, pp. 403-418.
- A. G. Ostrander, N. R. Carlson and K. L. Zonge, “Further Evidence of Electrical Anomalies over Hydrocarbon Accumulations Using CSAMT,” 53rd Annual SEG Meeting, Dallas, Expanded Abstracts, 1983, pp. 60-63.
- L. C. Bartel and R. D. Jacobson, “Results of a Controlled Source Audio frequency Magnetotelluric Survey at the Puhimau Thermal Area,” Geophysics, Vol. 52, 1987, pp. 665-677
- Y. Sasaki, Y. Yoshihiro and K. Matsuo, “Resistivity Imaging of Controlled-Source Audio Frequency Magnetotelluric Data,” Geophysics, Vol. 57, No. 7, 1992, pp. 952-955.
- M. Yamashita, P. G. Hallof and W. H. Pelton, “CSAMT Case Historis with a Multichannel CSAMT System and near Field Data Correction,” 55th SEG Annual Convention, 1985, pp. 276-278.
- A. A. Kaufmann and G. V. Keller, “Frequency and Transient Sounding,” Elsevier, Amsterdam, 1983.
- S. H. Ward and G. W. dan Hohmann, “Electromagnetic Theory for Geophysical Applications,” In: M. N. Nabighian, Ed., Electromagnetic Methods, Theory and Practice, Society of Exploration Geophysicist, Vol. 1, 1988, pp. 131-311.
- N. P. Singh and T. Mogi, “EMDPLER: A F77 Program for Modeling the EM Response of Dipolar Sources over the Non Magnetic Layer Earth Model,” Computer and Geosciences, Vol. 36, No. 4, 2010, pp. 430-440. doi:10.1016/j.cageo.2009.08.009
- C. H. Stoyer and R. J. Greenfield, “Numerical Solutions of the Response of a Two Dimensional Earth to an Oscillating Magnetic Dipole Source,” Geophysics, Vol. 41, No. 3, 1976, pp. 519-530.