1887
Volume 49, Issue 3
  • ISSN: 0812-3985
  • E-ISSN: 1834-7533

Abstract

[

3D controlled-source audio frequency magnetotelluric (CSAMT) responses can be distorted strongly by topography and should be accounted for in data inversion and interpretation. In this paper we present a scheme to incorporate topographic distortions into the inversion instead of correcting them. This approach has been verified by comparing the modelling results with 2D FEM CSAMT solutions and synthetic inversion examples. Compared with the responses generated from a half-space model with flat surface, it is found that not only the topography in the survey area but also that at the source position may strongly distort the CSAMT responses. The field example indicates that results with topography are much better than those without considering topography to map the distribution of coal seam underground, which also illustrates the effectiveness of our approach.

,

In this paper, we present a scheme to incorporate 3D controlled-source audio frequency magnetotelluric (CSAMT) topographic distortions into the 3D inversion instead of correcting them. This approach has been verified by comparison with 2D FEM CSAMT solutions and synthetic inversion examples. The field example also illustrates the effectiveness of our approach.

]
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2018-06-01
2026-01-24

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/content/journals/10.1071/EG16067
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Three-dimensional inversion of CSAMT data in the presence of topography
Exploration Geophysics 49, 253 (2018); https://doi.org/10.1071/EG16067
/content/journals/10.1071/EG16067
/content/journals/10.1071/EG16067
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  • Article Type: Research Article
Keyword(s): 3D inversion; CSAMT; topography

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