1887
Volume 42, Issue 2
  • ISSN: 0812-3985
  • E-ISSN: 1834-7533

Abstract

Abstract

P-wave reflection-statics solutions typically incorporate P-wave refraction data, derived from the first breaks of the production data. Similarly, converted-wave refractions, taken from inline-component recordings, can be exploited to yield S-wave receiver statics, required in the processing of converted-wave reflection data. This methodology requires extensions to well known P-wave refraction analysis methods. This paper outlines extensions of the slope-intercept method and the reciprocal method, required to analyse converted-wave refractions. We discuss the computation of S-wave time-depths and describe how the observed ratio of S-wave to P-wave time-depths can provide a useful estimate of the near-surface / ratio, which is of interest in the analysis of engineering rock strengths.

We also include discussion of several related practical issues, with particular reference to dynamite sources. When the source is buried in the refractor, the required reciprocal times cannot be directly measured from the raw travel-time data. They can, however, be easily derived via correction using measured intercept times. Often converted-wave refractions are of poorer quality than conventional P-wave refractions, such that reversed refractions may not be available over some parts of the spread. In this situation, the preferred time-depth quantity cannot be computed. However, delay-times derived from single-ended data can be substituted, particularly if lateral variations in refractor velocity are allowed for.

The concepts outlined here are used in a companion paper to correct S-wave receiver statics in a coal-scale dataset from the Bowen Basin in central Queensland.

Loading

Article metrics loading...

/content/journals/10.1071/EG10030
2011-06-01
2026-01-17
Loading full text...

Full text loading...

References

  1. Edge, A. B., and Laby, T. H., 1931, The Principles and Practice of Geophysical Prospecting: being the report of the Imperial Geophysical Experimental Survey: University Press.
  2. Gardner L. W. 1939 An areal plan of mapping subsurface structure by refraction shooting: Geophysics 4 247 259 10.1190/1.1440501
    https://doi.org/10.1190/1.1440501 [Google Scholar]
  3. Hagedoorn J. G. 1959 The plus-minus method of interpreting seismic refraction lines: Geophysical Prospecting 6 285 314
    [Google Scholar]
  4. Hagiwara T. Omote S. 1939 Land creep at Mt Tyausu – Yama (Determination of slip plane by seismic prospecting): Tokyo University Earthquake Research Institute Bulletin 17 118 137
    [Google Scholar]
  5. Hawkins L. V. 1961 The reciprocal method of routine shallow seismic refraction investigations: Geophysics 26 806 819 10.1190/1.1438961
    https://doi.org/10.1190/1.1438961 [Google Scholar]
  6. Knox, W. A., 1967, Multilayer near-surface refraction computations, in A.W. Musgrave, ed., Seismic refraction prospecting: Society of Exploration Geophysicists, 197–216.
    [Google Scholar]
  7. Li X. Y. Dai H. Mueller M. Barkved O. 2001 Compensating for the effects of gas clouds on C-wave imaging: a case study from Valhall: The Leading Edge 20 1022 1028 10.1190/1.1487307
    https://doi.org/10.1190/1.1487307 [Google Scholar]
  8. Meulenbroek A. Hearn S. 2011 Analysis of converted-refractions for shear statics and near-surface characterisation: Exploration Geophysics 42 147 154 10.1071/EG10031
    https://doi.org/10.1071/EG10031 [Google Scholar]
  9. Musgrave, A. W., 1967, ed., Seismic refraction prospecting: Society of Exploration Geophysicists.
    [Google Scholar]
  10. Nettleton, L. L., 1940, Geophysical prospecting for oil: McGraw Hill.
    [Google Scholar]
  11. Palmer D. 1981 An introduction to the generalized reciprocal method of seismic refraction interpretation: Geophysics 46 1508 1518 10.1190/1.1441157
    https://doi.org/10.1190/1.1441157 [Google Scholar]
  12. Palmer, D., 1986, Refraction seismics – The lateral resolution of structure and seismic velocity: Geophysical Press.
    [Google Scholar]
  13. Thompson L. 1999 Converted-wave reflection seismology over inhomogeneous, anisotropic media: Geophysics 64 678 690 10.1190/1.1444577
    https://doi.org/10.1190/1.1444577 [Google Scholar]
/content/journals/10.1071/EG10030
Loading
/content/journals/10.1071/EG10030
Loading

Data & Media loading...

Most Cited This Month Most Cited RSS feed

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