The first tidal analysis based on the CG-5 Autograv gravity measurements at Modra station

Michal MIKOLAJ; Branislav HÁBEL

doi:10.2478/congeo-2013-0004

Michal MIKOLAJ Department of Theoretical Geodesy Faculty of Civil Engineering Slovak University of Technology
Branislav HÁBEL Department of Theoretical Geodesy Faculty of Civil Engineering Slovak University of Technology

DOI: https://doi.org/10.2478/congeo-2013-0004

Keywords: tidal parameters, amplitude factor, gravimeter, relative gravity measurements, tidal analysis

Abstract

We present the tidal parameters estimated for the absolute gravity site in
Modra (Slovakia). This is the first tidal analysis based on gravity measurements for this
location. Relative gravity variations observed by Scintrex CG-5 Autograv gravimeter were
used for the tidal analysis. We observed large and non-linear instrumental drift which
cannot be effectively eliminated by polynomial approximation. Drift was eliminated by a
filtering. New set of tidal parameters was estimated and analyzed with the focus on diurnal
and semi-diurnal tidal waves. Time and frequency domain comparison between new
parameters and those obtained from the superconducting gravimeter located in Vienna
was performed. A maximum amplitude factor difference of 0.2% was found between main
tidal waves corrected for ocean tides and non-hydrostatic body tide model. New estimated
tidal parameters can serve for the correction of local relative gravity measurements.

Author Biographies

Michal MIKOLAJ, Department of Theoretical Geodesy Faculty of Civil Engineering Slovak University of Technology

Radlinského 11, 813 68 Bratislava, Slovak Republic

Branislav HÁBEL, Department of Theoretical Geodesy Faculty of Civil Engineering Slovak University of Technology

Radlinského 11, 813 68 Bratislava, Slovak Republic