Volume 32 Number 1
  • E-ISSN: 1365-2478



The most common source of seismic energy is an explosion at some depth in a borehole. The radiated waves are reflected not only at the subsurface layers but also at the free surface. The earth's surface acts as a generator of both P‐ and S‐waves.

If the source depth is much less than the dominant wavelength the reflected waves resemble closely the waves generated by a single force. Theoretical seismograms were computed with different methods to look for the relevance of the surface‐reflected waves. The numerical experiments show reflected shear waves even for small shotpoint—receiver distances. Due to their polarization these waves can be detected most easily on in‐line horizontal geophones. The existence of these waves was examined during a conventional survey in Northern Germany. Conventional data analysis shows a large variability in the ν ratio. The method used here produced a shear‐wave section with a rather good signal‐to‐noise ratio down to 4 s S‐wave reflection time.


Article metrics loading...

Loading full text...

Full text loading...


  1. Aki, K. and Richards, P. G.1980, Quantitative Seismology, Theory and Methods, Vol. 1, W. H.Freeman , San Francisco .
    [Google Scholar]
  2. Ben‐Menahem, A. and Singh, S. J.1981, Seismic Waves and Sources, Springer‐Verlag, Berlin , Heidelberg , New York .
    [Google Scholar]
  3. Cerveny, V.1956, The reflection of spherical elastic waves at a plane boundary, Travaux de l'Institut Geophysique del'Academie Tehecoslovaque des Sciences44, 343–365.
    [Google Scholar]
  4. Dohr, G. and Janle, H.1980, Improvements in the observation of shear waves, Geophysical Prospecting28, 208–220.
    [Google Scholar]
  5. Fuchs, K. and Müller, G.1971, Computation of synthetic seismograms with the reflectivity method and comparison with observations, Geophysical Journal of the Royal Astronomical Society23, 417–433.
    [Google Scholar]
  6. Helbig, K. and Mesdag, C. S.1982, The potential of shear‐wave observations, Geophysical Prospecting30, 413–431.
    [Google Scholar]
  7. Hron, F. and Mikhailenko, B.1981, Numerical modeling of nongeometrical effects by the Alekseev—Mikhailenko method, Bulletin of the Seismological Society of America71, 1011–1029.
    [Google Scholar]
  8. Kind, R.1978, The reflectivity method for a buried source, Journal of Geophysics44, 603–612.
    [Google Scholar]
  9. Kummer, B.1983, Differenzenapproximationen des elastischen Wellenfeldes in isotropen, linearen Medien mit geneigten Grenzflächen, Dissertation, Universität Hamburg.
  10. Pilant, W. L.1979, Elastic Waves in the Earth, Elsevier, Amsterdam .
    [Google Scholar]
  • Article Type: Research Article
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