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Applied Geophysics

, Volume 15, Issue 3–4, pp 513–523 | Cite as

Three-dimensional numerical modeling of gravity anomalies based on Poisson equation in space-wavenumber mixed domain

  • Shi-Kun Dai
  • Dong-Dong ZhaoEmail author
  • Qian-Jiang Zhang
  • Kun Li
  • Qing-Rui Chen
  • Xu-Long Wang
Article
  • 8 Downloads

Abstract

In gravity-anomaly-based prospecting, the computational and memory requirements for practical numerical modeling are potentially enormous. Achieving an efficient and precise inversion for gravity anomaly imaging over large-scale and complex terrain requires additional methods. To this end, we have proposed a new topography-capable 3D numerical modeling method for gravity anomalies in space-wavenumber mixed domain. By performing a two-dimensional Fourier transform in the horizontal directions, threedimensional partial differential equations in the spatial domain were transformed into a group of independent, one-dimensional differential equations engaged with different wave numbers. These independent differential equations are highly parallel across different wave numbers. This method preserves the vertical component in the space domain, which is beneficial when modeling complex topography. The finite element method was used to solve the transformed differential equations with different wave numbers, and the efficiency of solving fixedbandwidth linear equations was further improved by a chasing method. In a synthetic test, a prism model was used to verify the accuracy and reliability of the proposed algorithm by comparing the numerical solution with the analytical solution. We studied the computational precision and efficiency with and without topography using different Fourier transform methods. The results showed that the Guass-FFT method has higher numerical precision, while the standard FFT method is superior, in terms of computation time, for inversion and quantitative interpretation under complicated terrain.

Keywords

Topography gravity anomaly space-wavenumber mixing domain threedimensional numerical modeling 

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Notes

Acknowledgements

The authors are very grateful to the three reviewers and editor-in-chief Fan Weicui for their critiques, helpful comments, and valuable suggestions which improved this manuscript significantly. In addition, we would like to thank Prof. Xu Yungui and Associate Prof. Chen Longwei for their guidance and help during the development of this paper.

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Copyright information

© Editorial Office of Applied Geophysics and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Shi-Kun Dai
    • 1
    • 2
  • Dong-Dong Zhao
    • 1
    • 2
    Email author
  • Qian-Jiang Zhang
    • 3
  • Kun Li
    • 1
    • 2
  • Qing-Rui Chen
    • 1
    • 2
  • Xu-Long Wang
    • 1
    • 2
  1. 1.School of Geosciences and Info-physicsCentral South UniversityChangshaChina
  2. 2.Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment MonitoringMinistry of Education (Central South University)ChangshaChina
  3. 3.School of College of Earth Sciences of Guilin university of technologyGuilinChina

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