1887
Volume 36 Number 3
  • E-ISSN: 1365-2478

Abstract

ABSTRACT

An in‐seam fan shoot was conducted in 1981 over a 300 m × 500 m panel of the Schwalbach seam at Ensdorf by a team from Prakla‐Seismos AG of Hannover under contract to Saarbergwerke AG, Saarbrücken. The object was to study SH‐mode propagation in the coal seam waveguide. The high quality dataset retrieved provides a general and valuable test bed with which to compare the performance of in‐seam seismic velocity analysers.

Five different dispersion analysers are demonstrated using the Schwalbach data. They are all based on the assumption of coal seam homogeneity and isotropy. Space or time windows limit the resolution of the Fourier moving‐window analyser, the migration based phase‐velocity analyser, and the double Fourier transformer. The other two analysers, the maximum entropy moving‐window analyser and the phase‐moveout analyser, achieve noise‐limited super‐resolution by predicting the probable behaviour of the wavefield outside the window.

The coal seam's characteristics conform to those predicted for a simplified model based on proposals by Elsen, Rüter and Schott of Westfälische Berggewerkschaftskasse, Bochum. The slight discrepancy between theoretical and actual dispersion characteristics could be reduced by increasing the model's complexity. However, there would be no material gain without testing the validity of the signal processing assumptions of seam isotropy and homogeneity.

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2006-04-27
2024-04-19
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References

  1. ARNETZL, H. and KLINGE, U.1982. Erfahrungen mit der Flözwellenseismik bei der Vorfelderkundung. Glückauf118, 658–664.
    [Google Scholar]
  2. BÅTH, M.1974. Spectral Analysis in Geophysics.Elsevier Scientific Press Pub. Co.
    [Google Scholar]
  3. BOOER, A.K., CHAMBERS, J. and MASON, I.M.1977. A fast numerical algorithm for the recompression of dispersed time signals. Electronics Letters13, 453–455.
    [Google Scholar]
  4. BRENTRUP, F.K.1979. Die Entwicklung einer schlagwettergeschützten Digitalapparatur fürdie Flözwellenseismik. Glückauf-Forschungshefte40, 11–15.
    [Google Scholar]
  5. BUCHANAN, D.J. and JACKSON, P.J.1983. Dispersion relation extraction by multi‐trace analysis. Bulletin of the Seismological Society of America73, 391–404.
    [Google Scholar]
  6. BUCKER, H.P.1977. Cross‐sensor beam with a sparse line array. Journal of the Acoustical Society of America61, 494–498.
    [Google Scholar]
  7. CLAYTON, R.W. and WIGGINS, R.A.1976. Source shape estimation and deconvolution of teleseismic body waves. Geophysical Journal of the Royal Astronomical Society47, 151–178.
    [Google Scholar]
  8. CONNOR, K.A. and FELSEN, L.B.1974. Complex space‐time rays and their application to pulse propagation in dispersive media. Proceedings of the IEEE61, 1586–1598.
    [Google Scholar]
  9. Cox, K.B.1986. High resolution analysis of dispersed seismic signals. D. Phil, thesis, University of Oxford.
  10. Cox, K.B. and MASON, I.M.1986. Maximum entropy analysis of dispersed seismic signals. Geophysics51, 2225–2234.
    [Google Scholar]
  11. DRESEN, L.1985. Flözwellenseismik für die untertägige Steinkohlenerkundung. Angewandte Geowissenschaften, Methoden der Angewandten Geophysik und Mathematische Verfahren in den Geowissenschaften, F.Bender (ed.), Vol. 11, pp. 111–129. Ferdinand Enke Verlag.
    [Google Scholar]
  12. DZIEWONSKI, A. and HALES, A.1972. Numerical analysis of dispersed seismic waves. Methods of Computational PhysicsII, pp. 39–85Academic Press.
    [Google Scholar]
  13. EVISON, F.F.1955. A coal seam as a guide for seismic energy. Nature176, 1224–1225.
    [Google Scholar]
  14. FRANSSENS, G.R., LAGASSE, P.E. and MASON, I.M.1985. Study of the leaking channel modes of in‐seam exploration seismology by means of synthetic seismograms. Geophysics50, 414–424.
    [Google Scholar]
  15. KRAJEWSKI, P., DRESEN, L., SCHOTT, W. and RÜTER, H.1987. Studies of roadway modes in a coal seam by dispersion and polarisation analysis, a case history. Geophysical Prospecting35, 767–786.
    [Google Scholar]
  16. KREY, TH. C.1963. Channel waves as a tool of applied geophysics in coal mining. Geophysics28, 701–714.
    [Google Scholar]
  17. JUSTICE, J.H.1985. Array processing in exploration seismology. Array Signal Processing, S.Haykin (ed), pp. 6–114. Prentice‐Hall, Inc.
    [Google Scholar]
  18. MASON, I.M., BUCHANAN, D.J. and BOOER, A.K.1980. Fault location by underground seismic survey. Proceedings of the IEEE127, 322–336.
    [Google Scholar]
  19. MASON, I.M.1981. Algebraic reconstruction of a two‐dimensional velocity inhomogeneity in the High Hazles seam of Thoresby colliery. Geophysics46, 298–308.
    [Google Scholar]
  20. MOFFET, A.J.1968. Minimum redundancy linear arrays. IEEET‐AP 16, (2), 172–175.
    [Google Scholar]
  21. NUTTALL, A.H., CARTER, G.C. and MONTAVON, E.M.1974. Estimation of the 2‐D spectrum of a space time noise field for a sparse array. Journal of the Acoustical Society of America55, 1034–1041.
    [Google Scholar]
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