Contrary to intuition, draped aeromagnetic surveys (when compared to typical level surveys, amplify, rather than reduce, the problem of magnetic-terrain anomalies. Calculations of the total magnetic field of various simple magnetic topographies on level and draped surfaces support this conclusion. In cases where draped surfaces are lower than level surfaces, the draped profiles exhibit steeper gradients and deeper polarity lows over topography than do the level profiles. On the other hand, where draped surfaces are higher than level surfaces, all anomalies are attenuated, so that magnetic-terrain effects might be reduced relative to subsurface sources (depending upon the magnetization of each). The difference in magnetic behavior between level and draped data can be explained by a contribution of a vertical derivative component in the draped case that is absent in the level case. The contribution is most significant near topographic features because both the observation surface and the topographic surface are changing vertically. (Author)

  • Availability:
  • Corporate Authors:

    American Geophysical Union

    2000 Florida Avenue, NW
    Washington, DC  United States  20009-1277
  • Authors:
    • Grauch, VJS
    • Campbell, D
  • Publication Date: 1983-12-13

Media Info

  • Pagination: p. 984
  • Serial:
    • EOS Transactions
    • Volume: 64
    • Issue Number: 50
    • Publisher: American Geophysical Union
    • ISSN: 0096-3941

Subject/Index Terms

Filing Info

  • Accession Number: 00381244
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Mar 30 1984 12:00AM