First six months of Superconducting Gravimetry in Argentina
21/09/2016 | 16:30 | Session 4: Global gravity field modelling
Author(s): Claudia Tocho, Ezequiel Antokoletz and Dr.-Ing. Hartmut Wziontek
Claudia Tocho, Ezequiel Antokoletz and Dr.-Ing. Hartmut Wziontek
On December 16th, 2015, the Superconducting Gravimeter (SG) RW-038 began to measure again after it was moved from the old station in Concepcion, Chile to the Argentinian-Germany Geodesy Observatory (AGGO) near the city of La Plata, Argentina.
The SG data enables research in several geodetic and geophysical studies that involve Earth’s changes in the surface gravity field. In particular, it allows computing local models of tidal parameters. The Superconducting Gravimeter RW-038 in AGGO’s station will be used to monitor the tidal signal for a period of the first six months after its installation.
The residual gravity series were obtained by removing the principal constituents of the largest influences of thegravity signalthat can be modeled with some confidence like the atmospheric effects, theoretical Earth tides, ocean loading effect, drift and pole tides. Then, in the residual signalspikes were fixed, earthquake perturbationswere reduced and gaps were filled up using TSOFT pre-processing package. Finally, when all problems have been fixed in the residuals, the previously removed signals have to be restored to obtain the corrected gravity signal.
Recently the transfer function of the SG was determined by analyzing the step response of the whole system. Empirical amplitude and phase response functions will be presented. The group delay at zero frequency was used in tidal analysis.
Through a harmonic analysis of the preprocessed hourly data,parameters (amplitude factors and phases) of tidal waves withinspecific frequency rangeswere estimated using ETERNA3.40 software package.