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Studia Geophysica et Geodaetica

, Volume 59, Issue 4, pp 524–537 | Cite as

Towards the measurement of zero vertical gradient of gravity on the Earth’s surface

  • Pavol ZahorecEmail author
  • Ján Mikuška
  • Juraj Papčo
  • Ivan Marušiak
  • Roland Karcol
  • Roman Pašteka
Article
  • 168 Downloads

Abstract

It is well known that the vertical gradient of gravity measured on the Earth’s surface depends strongly on nearby topographical shapes. We simply inverted the problem and posed the question whether a zero vertical gradient can be observed using relative gravity meters and the classical tower method of measurement in appropriate terrain conditions. Extensively using the model of a vertical cone to simulate the real in-field conditions, we have found that reversed-cone-shaped topographic depressions represent the most perspective forms, which can contribute to extremely small values of the resulting vertical gradient. In one such form, namely a karstic sinkhole, we measured the value of −0.071 mGal/m (10−5 s−2). In addition, we successfully modeled this value using a detailed local digital elevation model. We thus conclude that zero vertical gradient of gravity should be observable by common means, also on the Earth’s surface, and not only underground within very dense rocks as some ores can be. Once this is verified it could represent a contribution to the theory of the Earth’s gravity field and its geophysical as well as geodetic applications.

Keywords

normal gravity gradient synthetic topography model relative gravity measurement tower method sinkhole 

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Copyright information

© Institute of Geophysics of the ASCR, v.v.i 2015

Authors and Affiliations

  • Pavol Zahorec
    • 1
    Email author
  • Ján Mikuška
    • 2
  • Juraj Papčo
    • 3
  • Ivan Marušiak
    • 2
  • Roland Karcol
    • 1
  • Roman Pašteka
    • 4
  1. 1.Division of Geophysics, Earth Science InstituteSlovak Academy of SciencesBanská BystricaSlovak Republic
  2. 2.G-trend s.r.o.BratislavaSlovak Republic
  3. 3.Department of Theoretical Geodesy, Faculty of Civil EngineeringSlovak University of TechnologyBratislavaSlovak Republic
  4. 4.Department of Applied end Environmental Geophysics, Faculty of Natural SciencesComenius UniversityBratislavaSlovak Republic

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