1887
Volume 51, Issue 4
  • E-ISSN: 1365-2478

Abstract

ABSTRACT

The problem of removing directional trends frequently occurs in the processing of magnetic data and also in the subsequent steps of data interpretation. The so‐called corrugations are typical directional trends occurring in levelled data, which may be removed in several ways. Classical techniques are based on high‐pass filtering of the data and successively filtering these transformed data with directional cosine filters. Other linear features are due to real sources, such as pipelines in shallow surveys or dike swarms in regional surveys. They should, nevertheless, be considered as noise, due to the fact that their effect is strong and tends to hide the field features related to structures of more interest. We deal with both kinds of problem, presenting the results of a study in an archaeological area of southern Italy. Decorrugation of magnetic field anomalies is performed using a method based on the excellent space–frequency localization properties of wavelet bases, allowing a very sharp filtering of the field along a selected direction. We compare this technique with the classical one in a synthetic case and find that the wavelet decorrugation is simpler and produces low distortion maps. Besides the field decorrugation, the wavelet approach was also shown to be useful in the subsequent enhancement of the measured field. In fact, we show that the wavelet analysis offers a unique framework where various filtering problems (directional, isotropic, global or local as well) may be easily solved. As regards the archaeological case, strong noisy effects from elongated sources (pipelines) were successfully removed in a sharp and local way.

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2003-07-18
2020-04-02
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References

  1. FediM. and FlorioG.2001. Detection of potential fields source boundaries by enhanced horizontal derivative method. Geophysical Prospecting49, 40–58.
    [Google Scholar]
  2. FediM., LenarduzziL., PrimiceriR. and QuartaT.2000. Localized denoising filtering using the wavelet transform. PAGEOPH157(9), 1463–1491.
    [Google Scholar]
  3. FediM. and QuartaT.1998. Wavelet analysis for the regional–residual and local separation of potential field anomalies. Geophysical Prospecting46, 507–525.
    [Google Scholar]
  4. FerraccioliF., GambettaM. and BozzoE.1998. Microlevelling procedures applied to regional aeromagnetic data: an example from the Transantarctic Mountains ( Antarctica ). Geophysical Prospecting46, 177–196.
    [Google Scholar]
  5. Foufoula GeorgiouE. and KumarP.1994. Wavelets in Geophysics , p. 373. Academic Press, Inc.
    [Google Scholar]
  6. GastaldiP.1998. Annali del Dipartimento di Studi del mondo classico e del Mediterraneo antico: Pontecagnano, II.4 La necropoli del Pagliarone, Quad. n. 10 . Napoli.
    [Google Scholar]
  7. Geosoft
    Geosoft1998. OASIS, Geophysical Leveling Package . Geosoft Inc .
    [Google Scholar]
  8. HansenR.O.1984. Two approaches to total field reconstruction from gradiometer data. 54th SEG meeting, Atlanta , USA , Expanded Abstracts, 245–247.
  9. HsuS., SibuetJ.C. and ShyuC.1996. High‐resolution detection of geologic boundaries from potential field anomalies: An enhanced analytic signal technique. Geophysics61, 373–386.
    [Google Scholar]
  10. MallatS.1998. A Wavelet Tour of Signal Processing . Academic Press, Inc.
    [Google Scholar]
  11. MintyB.R.S.1991. Simple microlevelling for aeromagnetic data. Exploration Geophysics22, 591–592.
    [Google Scholar]
  12. NelsonJ.B.1994. Levelling total‐field aeromagnetic data with measured horizontal gradients. Geophysics59, 1166–1170.
    [Google Scholar]
  13. SowerbuttsW.T.C.1988. The use of geophysical methods to locate joints in underground metal pipelines. Quarterly Engineering Geology21, 273–281.
    [Google Scholar]
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