| Popis: |
The Argentinean-German Geodetic Observatory (AGGO) is a fundamental geodetic station located close to the city of La Plata, Argentina. Currently, at AGGO two gravity meters are operated: the superconducting gravimeter (SG) SG038, continuously recording gravity variations since 2016; and the absolute gravimeter (AG) FG5-227 which provides the station with an accurate gravity reference since 2018. The combination of both observations allowed not only the determination of the scale factor and instrumental drift of the SG038, but also the establishment of a gravity reference function supporting the future International Gravity Reference Frame (IGRF) on a regional level. The gravity reference function allows to predict absolute gravity values based on the SG observations and by this further monitoring of AGs. Recently, systematic deviations between this reference and the latest observations with FG5-227 observations up to a few μGal for some periods were detected. Therefore, the stability of the instrumental drift of the SG038 is re-evaluated, and possible AG offsets as well as alternative explanations are discussed. |
