Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Investigation of HEM Forward Modeling Accuracy on Inverse Modeling

Document Type : Original Research Paper

Authors
A.R. Arab-Amiri 1
A. Moradzadeh 2
D. Rajabi 1
N. Fathianpour 3
B. Siemon 4
1 Faculty of Mining, Petroleum and Geophysics, Shahrood University of Technology, Shahrood, Iran.
2 Faculty of Mining, Petroleum and Geophysics, Shahrood University of Technology, Shahrood, Iran
3 Faculty of Mining Engineering, Isfahan University of Technology (IUT), Isfahan, Iran
4 Federal Institute for Geosciences and Natural Resources (BGR), Hannover, Germany.
10.22071/gsj.2010.55362
Abstract
Today Helicopter-borne electromagnetic (HEM) data survey play important role for high resolution and fast 3D mapping of resistivity structures within the vast area. The standard method of interpretation of these data is to inverse them frequently. As surveying system is not fixed during the survey, hence noise is accompanying the measured data. To process the measured noisy data they are fed into the several filters to get better data to be used for modeling. During the filtering stage some of signals are also lost. Therefore, it is required to choose modeling techniques that has minimum error and provide accurate subsurface model. In this paper, first the response of the three synthetic layered earth models were calculated by using three different Hankel transform forward modeling methods. Then with adding different percents of random noise to the synthetic data, they were modeled inversely by different methods. The obtained results indicate that the so-called improved Guptasarma-Singh inverse modeling method could provide better responses for all three synthetic models.
Keywords
Helicopter-borne electromagnetic (HEM)
Forward modeling
Inverse modeling
Gupta method
Hankel method
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Scientific Quarterly Journal of Geosciences
Volume 20, Issue 77
Winter 2010
Pages 137-140