1887
Volume 18 Number 4
  • E-ISSN: 1365-2478

Abstract

A

In the theoretical part of the present paper, formulas have been analyzed for a magnetic dipole in a homogeneous and unbounded medium. The magnetic field is elliptically polarized in the region between the quasistatic zone and the far field. Since the position and the shape of the polarization ellipses depend on the complex wave number, , it is possible to determine by measuring the polarization ellipses. From , the conductivity and the dielectric constant of the medium are easily calculated. The functions required for the measuring method have been computed and plotted in graphs.

In the experimental part it was examined how far the theory may be applied to measurements of propagation through rock at frequencies ranging from 100‐1000 kHz. These measurements showed that reasonably defined mean values of rock parameters can be given only if the deviations of the field from the theoretically expected field are not too high. These deviations have been named field distortions and have been examined by means of statistical methods (variance ratio tests). Gallery cavity and inhomogeneity or anisotropy of the medium account for these distortions.

Loading

Article metrics loading...

/content/journals/10.1111/j.1365-2478.1970.tb02127.x
2006-04-27
2024-04-24
Loading full text...

Full text loading...

References

  1. de Bettencourt, J. T. and J. W.Frazier, 1963, Rock electrical characteristics deduced from attenuation rates. IEEE Trans. AP‐11, 358–363.
    [Google Scholar]
  2. Bitterlich, W., 1963, Third Technical Annual Summary Report: On the propagation of VLF waves in solids. Contract No. 61 (052)‐490, Innsbruck.
  3. Bitterlich, W., 1967, Die Ausbreitung von VLF‐Wellen durch das Erdinnere, Acta Physica Austriaca27, 183–210.
    [Google Scholar]
  4. Bitterlich, W., 1967a, Magnetische Dipolantennen für Feldstärkemessungen im LF‐ und im VLF‐Bereich. Internat. Elektron. Rundschau21, 225–228.
    [Google Scholar]
  5. Dokoupil, S. and J.Karpinskiy, 1962, The attenuation of electromagnetic waves through rock. Studia geoph. et geod.6, 176–192.
    [Google Scholar]
  6. Greene, F. M., 1967, The near zone magnetic field of a small loop antenna. Journ. Res. N.B.S. 71 C, 319.
    [Google Scholar]
  7. Gröbner, O., 1964, Über die Ausbreitung sehr langer elektromagnetischer Wellen im Gestein, Diss, (thesis) Innsbruck .
  8. Kellner, A. W., 1969, Die Bestimmung elektrischer Gesteinsparameter aus der Feldstruktur eines magnetischen Dipols. Diss, (thesis) Innsbruck .
  9. Linder, A., 1964, Statist. Methoden , Birkhäuser , Basel .
    [Google Scholar]
  10. Lukavec, R., 1969, Über die Eigenschaften kleiner, eigenresonanter Wendelantennen bei niedrigen Frequenzen und ihre Felder in dissipativen Medien. Diss, (thesis) Innsbruck .
  11. Nessler, N., 1967, Die Ausbreitung langer elektromagnetischer Wellen durch homogene und inhomogene feste Medien. Diss, (thesis) Innsbruck .
  12. Tsao, C. K. H. and J. T. deBettencourt, 1967, Measurement of the phase constant for rock propagated signals. IEEE Trans, on communication technology, COM‐15, 592–597.
    [Google Scholar]
  13. Wait, J. R., 1952, The magnetic dipole antenna immersed in a conducting medium. Proc. I.R.E.40, 1244–1245.
    [Google Scholar]
  14. Wöbking, H., 1968, Über den Frequenzgang der Dielektrizitätskonstante und der elektrischen Leitfähigkeit bei Gesteinen und über die Bedeutung der elektrischen Gesteinsparameter für die Bestimmung gefügekundlicher Größen. Diss, (thesis) Innsbruck .
http://instance.metastore.ingenta.com/content/journals/10.1111/j.1365-2478.1970.tb02127.x
Loading
  • Article Type: Research Article

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