Comments on Gravity Reduction and Gravity Anomaly

중력 보정과 중력 이상에 대한 이해

  • Park, Yeong-Sue (Geology and Geoinformation Division, Korea Institute of Geoscience and Mineral Resources) ;
  • Lim, Mu-Taek (Geology and Geoinformation Division, Korea Institute of Geoscience and Mineral Resources) ;
  • Rim, Hyoung-Rae (Geology and Geoinformation Division, Korea Institute of Geoscience and Mineral Resources)
  • 박영수 (한국지질자원연구원 지질기반정보연구부) ;
  • 임무택 (한국지질자원연구원 지질기반정보연구부) ;
  • 임형래 (한국지질자원연구원 지질기반정보연구부)
  • Published : 2006.05.31

Abstract

Gravity reduction and Bouguer anomaly are frequently misunderstood by many geoscientists as follows; the observed gravity is reduced to a common datum plane, so that gravity effects by all materials above the datum is removed, therefore, Bouguer anomaly is located on the datum plane. In reality, Bouguer anomaly does not lie on a common datum plane, but is difference between observed gravity and reference gravity at the actual point of measurement. Commonly used gravity reduction formulas are approximate formulas. Here, we introduce complete formulas, and suggest to use them for more accurate results. We also suggest to use not the geoid but the reference ellipsoid as the vertical datum.

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