1887

Abstract

Summary

We present a flexible algorithm for modelling of 3D direct current (DC) resistivity and time-domain induced polarization (IP) data. A structured model mesh allows easy implantation of constrains, whereas the finite-element forward algorithm is based on unstructured tetrahedral meshes and therefore handles both topography, arbitrary shaped boundaries and local refinement. This, together with modelling of the secondary potential field for singularity removal around the sources, ensures high accuracy. Electrodes may be placed on the boundaries or arbitrarily in the subsurface thus allowing both surface and cross-borehole applications. The forward response is computed in frequency-domain and then transformed to time-domain using the Hankel Transform, taking into account the current waveform and system filters for a quantitative IP modelling of either full-decay IP responses or integral chargeability allowing the IP phenomenon to be parameterised using any IP parameterization. An accuracy test of the forward response shows the advantages of the singularity removal (computing primary and secondary potential fields separately) as it decreases the relative deviation to the analytic solution significantly compared to computing the total field.

Loading

Article metrics loading...

/content/papers/10.3997/2214-4609.201902461
2019-09-08
2024-04-20
Loading full text...

Full text loading...

References

  1. ChristensenN.K., FerreT.P., FiandacaG., ChristensenS.
    , 2017. Voxel inversion of airborne electromagnetic data for improved groundwater model construction and prediction accuracy, Hydrology and Earth System Sciences; 21(2), 1321–1337.
    [Google Scholar]
  2. ColeK.S. and ColeR.H.
    1941. Dispersion and absorption in dielectrics. Journal of Chemical Physics9, 341–351.
    [Google Scholar]
  3. Dey, A. and Morrison, H. F.
    , 1979, Resistivity Modeling for Arbitrarily Shaped 2-Dimensional Structures: Geophysical Prospecting, 27, 106–136.
    [Google Scholar]
  4. Fiandaca, G., Auken, E., Gazoty, A. and Christiansen, A.V.
    , 2012, Time-domain induced polarization: Full-decay forward modeling and 1D laterally constrained inversion of Cole-Cole parameters: Geophysics, 77, E213–E225.
    [Google Scholar]
  5. Fiandaca, G., Ramm, J., Binley, A., Gazoty, A., Christiansen, A.V. and Auken, E.
    , 2013, Resolving spectral information from time domain induced polarization data through 2-D inversion: Geophysical Journal International, 192, 631–646.
    [Google Scholar]
  6. FiandacaG., AukenE., ChristiansenA. & KirkegaardC.
    , 2013. Voxel inversion of airborne EM data, Near Surface Geoscience 2013-19th EAGE European Meeting of Environmental and Engineering Geophysics, 1–4. 10.3997/2214‑4609.20131426.
    https://doi.org/10.3997/2214-4609.20131426 [Google Scholar]
  7. FiandacaG., MadsenL.M., Maurya, P.K.
    , 2018, Re-parameterization of the Cole-Cole model for improved spectral inversion of induced polarization data. Near Surface Geophysics16, 385–399.
    [Google Scholar]
  8. Günther, T., Rücker, C. and Spitzer, K.
    , 2006, Three-dimensional modelling and inversion of dc resistivity data incorporating topography - II. Inversion: Geophysical Journal International, 166, 506–517.
    [Google Scholar]
  9. JinJ.M.
    2014, The finite element method in electromagnetics. Wiley, 3rd edition.
    [Google Scholar]
  10. PeltonW.H., WardS.H., HallofP.G., SillW.R. and NelsonP.H.
    , 1978. Mineral discrimination and removal of inductive coupling with multi-frequency IP. Geophysics43, 588–609.
    [Google Scholar]
  11. Rücker, C., Günther, T. and Spitzer, K.
    , 2006, Three-dimensional modelling and inversion of dc resistivity data incorporating topography - I. Modelling: Geophysical Journal International, 166, 495–505.
    [Google Scholar]
http://instance.metastore.ingenta.com/content/papers/10.3997/2214-4609.201902461
Loading
/content/papers/10.3997/2214-4609.201902461
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error